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Royal Holloway, University of London
1.
Eggleston, Richard.
An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector.
Degree: PhD, 2016, Royal Holloway, University of London
URL: https://pure.royalholloway.ac.uk/portal/en/publications/an-analysis-of-a-dataset-from-a-prototype-dark-matter-detector-and-the-design-simulation-and-construction-of-a-new-detector(f5f9f308-79a4-46a1-85c0-8a665f60050f).html
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https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792504
► Dark matter is considered one of the most significant outstanding problems in modern physics. Over the years a number of experimental techniques have been developed…
(more)
▼ Dark matter is considered one of the most significant outstanding problems in modern physics. Over the years a number of experimental techniques have been developed with the aim of making a direct detection. The Dark Matter Time Projection Chamber (DMTPC) collaboration uses gasesous CF4 in a time projection chamber (TPC) with charge and imaging readout. The work presented in this thesis represents an analysis on an existing detector with the aim of understanding the backgrounds that are present and improving techniques to reject them from the data. Following this, the design, fabrication and commissioning of a new large-scale detector is described, with focus on reduction of backgrounds from component materials. The process of analysing the data, results in an improvement to the background rejection methods. A reduction in the overall rate of events passing the selection criteria is observed, verifying the improvement. The upper limit on the spin-dependent dark matter-proton interaction cross-section is comparable to the previous analysis despite having lower total exposure. The value achieved is σpSD = 6.88×10-33 cm2 for a dark matter mass of 145 Gev/c2. A background estimation is presented providing evidence that the remaining candidate events can be attributed to radon progeny recoils, present due to radon emanating from and plated out on the materials that comprise the detector. This finding is used to drive the design of the next detector. This is done by producing a metric which satisfies the desired fiducial volume whilst minimising the surface area contributions of materials. The final field cage design reduces the surface-area to fiducial-volume ratio by a factor of 9.5 compared to the previous detector prototype and a factor of 28 compared to the first prototype (the detector used for the analysis of this thesis).
Subjects/Keywords: Dark Matter
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Chicago ·
MLA ·
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APA (6th Edition):
Eggleston, R. (2016). An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector. (Doctoral Dissertation). Royal Holloway, University of London. Retrieved from https://pure.royalholloway.ac.uk/portal/en/publications/an-analysis-of-a-dataset-from-a-prototype-dark-matter-detector-and-the-design-simulation-and-construction-of-a-new-detector(f5f9f308-79a4-46a1-85c0-8a665f60050f).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792504
Chicago Manual of Style (16th Edition):
Eggleston, Richard. “An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector.” 2016. Doctoral Dissertation, Royal Holloway, University of London. Accessed March 03, 2021.
https://pure.royalholloway.ac.uk/portal/en/publications/an-analysis-of-a-dataset-from-a-prototype-dark-matter-detector-and-the-design-simulation-and-construction-of-a-new-detector(f5f9f308-79a4-46a1-85c0-8a665f60050f).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792504.
MLA Handbook (7th Edition):
Eggleston, Richard. “An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector.” 2016. Web. 03 Mar 2021.
Vancouver:
Eggleston R. An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector. [Internet] [Doctoral dissertation]. Royal Holloway, University of London; 2016. [cited 2021 Mar 03].
Available from: https://pure.royalholloway.ac.uk/portal/en/publications/an-analysis-of-a-dataset-from-a-prototype-dark-matter-detector-and-the-design-simulation-and-construction-of-a-new-detector(f5f9f308-79a4-46a1-85c0-8a665f60050f).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792504.
Council of Science Editors:
Eggleston R. An analysis of a dataset from a prototype dark matter detector and the design, simulation and construction of a new detector. [Doctoral Dissertation]. Royal Holloway, University of London; 2016. Available from: https://pure.royalholloway.ac.uk/portal/en/publications/an-analysis-of-a-dataset-from-a-prototype-dark-matter-detector-and-the-design-simulation-and-construction-of-a-new-detector(f5f9f308-79a4-46a1-85c0-8a665f60050f).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792504
2.
Blackadder, Ian Gordon.
Dark Matter Decaying in the Expanding Universe.
Degree: PhD, Physics, 2016, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:674367/
► The last few years have seen significant interest in decaying dark matter. Specific models have been conjectured to account for observations that are not predicted…
(more)
▼ The last few years have seen significant interest in
decaying
dark matter. Specific models have been conjectured to
account for observations that are not predicted by the standard
cosmological model concerning issues of structure formation and
anomalous particle observations. I present a study of cosmological
implications of generic
dark matter decays. The aim of this thesis
is to understand features of
dark matter decay in a general, model
independent fashion. I consider two-body and many-body decaying
scenarios where the parent particle decays into a massive daughter
particle and one or more massless particles. In the two-body case
the massive daughter particle has a possibly relativistic kick
velocity and thus possesses a dynamical equation of state. In the
many-body decaying scenario there are many massless daughter
particles together with a massive daughter particle at rest. I
implement these
dark matter decaying scenarios in a broader
cosmological context, and explore the lifetime and energy budget of
decays throughout the history of the Universe, from the early
Universe and Big Bang Nucleosynthesis to the Cosmic Microwave
Background, Baryon Acoustic Oscillations and Type Ia supernovae to
the present epoch.
Advisors/Committee Members: Koushiappas, Savvas (Director), Dell'Antonio, Ian (Reader), Tucker, Greg (Reader).
Subjects/Keywords: Dark Matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Blackadder, I. G. (2016). Dark Matter Decaying in the Expanding Universe. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:674367/
Chicago Manual of Style (16th Edition):
Blackadder, Ian Gordon. “Dark Matter Decaying in the Expanding Universe.” 2016. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:674367/.
MLA Handbook (7th Edition):
Blackadder, Ian Gordon. “Dark Matter Decaying in the Expanding Universe.” 2016. Web. 03 Mar 2021.
Vancouver:
Blackadder IG. Dark Matter Decaying in the Expanding Universe. [Internet] [Doctoral dissertation]. Brown University; 2016. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:674367/.
Council of Science Editors:
Blackadder IG. Dark Matter Decaying in the Expanding Universe. [Doctoral Dissertation]. Brown University; 2016. Available from: https://repository.library.brown.edu/studio/item/bdr:674367/
3.
Chapman, Jeremy J.
First WIMP Search Results from the LUX Dark Matter
Experiment.
Degree: PhD, Physics, 2014, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:386289/
► A wealth of astrophysical evidence confirms that 26% of the energy density of the universe is comprised of a mysterious, non-baryonic, dark matter. A leading…
(more)
▼ A wealth of astrophysical evidence confirms that 26%
of the energy density of the universe is comprised of a mysterious,
non-baryonic,
dark matter. A leading candidate for
dark matter is
the Weakly Interacting Massive Particle (WIMP) that is suggested
both by the relic abundance of
dark matter, and extensions to the
standard model of particle physics. WIMPs interact with baryonic
matter only through gravity and the weak nuclear force. The Large
Underground Xenon (LUX)
dark matter experiment aims to detect WIMPs
through this weak interaction. LUX is a 370 kg two-phase
(liquid/gas) xenon time projection chamber designed to detect
nuclear recoils from interactions with WIMPs. Particle interactions
in LUX are observed by 122 photomultiplier tubes (PMTs). Signals
from these PMTs are processed by custom-built analog electronics.
The data acquisition system (DAQ) is composed of commercial
digitizers with firmware customized for the LUX experiment. The LUX
DAQ is optimized to provide a high rate and a large dynamic range
during precision calibrations involving radioactive sources, while
also delivering a low threshold for maximum sensitivity. The LUX
detector is housed in a 300 tonne water tank on the 4850 ft level
of the Sanford Underground Research Facility, in Lead, SD. The
first WIMP search results are based on 85.3 live-days of
data-taking. This non-blind analysis yields 160 events in the WIMP
search energy range in a 118kg fiducial volume. A profile
likelihood analysis of this data supports the background-only
hypothesis, producing the highest constraint on the WIMP-nucleon
interaction cross-section to date. The minimum 90% C.L. upper limit
is 7.6x10^-46 cm2 for a WIMP mass of 33 GeV/c2. In particular this
run has strongly ruled out hints of signal in the low-mass regime
between 6 and 20 GeV/c2 recently suggested by several direct
detection experiments. LUX will continue to undergo engineering and
calibrations runs to improve detector sensitivity. The subsequent
300 live-day blinded WIMP search will extend the WIMP limit of LUX
by a factor of x5 above a mass of 20 GeV/c2.
Advisors/Committee Members: Gaitskell, Richard (Director), Narain, Meenakshi (Reader), Tucker, Greg (Reader).
Subjects/Keywords: dark matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chapman, J. J. (2014). First WIMP Search Results from the LUX Dark Matter
Experiment. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:386289/
Chicago Manual of Style (16th Edition):
Chapman, Jeremy J. “First WIMP Search Results from the LUX Dark Matter
Experiment.” 2014. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:386289/.
MLA Handbook (7th Edition):
Chapman, Jeremy J. “First WIMP Search Results from the LUX Dark Matter
Experiment.” 2014. Web. 03 Mar 2021.
Vancouver:
Chapman JJ. First WIMP Search Results from the LUX Dark Matter
Experiment. [Internet] [Doctoral dissertation]. Brown University; 2014. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:386289/.
Council of Science Editors:
Chapman JJ. First WIMP Search Results from the LUX Dark Matter
Experiment. [Doctoral Dissertation]. Brown University; 2014. Available from: https://repository.library.brown.edu/studio/item/bdr:386289/
4.
Geringer-Sameth, Alex.
Comprehensive Approaches and Results in the Indirect Dark
Matter Search.
Degree: PhD, Physics, 2013, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:320646/
► Dark matter is an essential ingredient in our modern understanding of the Universe. However, its fundamental role in cosmology is matched only by its conspicuous…
(more)
▼ Dark matter is an essential ingredient in our modern
understanding of the Universe. However, its fundamental role in
cosmology is matched only by its conspicuous absence from the
Standard Model of particle physics. The last thirty years has seen
a concerted theoretical and experimental effort to identify the
particle nature of
dark matter.
In this thesis I present new work that pushes current
observations to the sensitivities required to explore long-standing
and broad classes of
dark matter candidates. I have developed a
maximally-powerful statistical framework that allows a simultaneous
analysis of multiple targets, taking into account the spatial and
spectral properties of individual detector events. The method is
applied to search for
dark matter annihilation in Milky Way dwarf
galaxies. This search currently represents the most sensitive probe
of
dark matter parameter space, for the first time excluding
annihilation cross sections which explain the observed relic
abundance.
In addition, I present two novel techniques developed to
understand the diffuse backgrounds which limit the sensitivity of
all astrophysical analyses, including
dark matter searches. The
first is a spacetime correlation function that is sensitive to a
population of extremely faint moving sources. The second makes use
of time series analyses in untangling the emission from unresolved
pulsars. Both methods are intended to discover and characterize an
entire population of sources even when the individual members
remain undetectable.
Advisors/Committee Members: Koushiappas, Savvas (Director), Dell'Antonio, Ian (Reader), Gaitskell, Richard (Reader).
Subjects/Keywords: dark matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Geringer-Sameth, A. (2013). Comprehensive Approaches and Results in the Indirect Dark
Matter Search. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:320646/
Chicago Manual of Style (16th Edition):
Geringer-Sameth, Alex. “Comprehensive Approaches and Results in the Indirect Dark
Matter Search.” 2013. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:320646/.
MLA Handbook (7th Edition):
Geringer-Sameth, Alex. “Comprehensive Approaches and Results in the Indirect Dark
Matter Search.” 2013. Web. 03 Mar 2021.
Vancouver:
Geringer-Sameth A. Comprehensive Approaches and Results in the Indirect Dark
Matter Search. [Internet] [Doctoral dissertation]. Brown University; 2013. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:320646/.
Council of Science Editors:
Geringer-Sameth A. Comprehensive Approaches and Results in the Indirect Dark
Matter Search. [Doctoral Dissertation]. Brown University; 2013. Available from: https://repository.library.brown.edu/studio/item/bdr:320646/
5.
Huwe, Paul M.
Dark Matter Substructure in High Redshift Clusters of
Galaxies.
Degree: PhD, Physics, 2013, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:320536/
► For my graduate research, I have focused on the creation of high resolution weak lensing mass maps in order to study dark matter substructure in…
(more)
▼ For my graduate research, I have focused on the
creation of high resolution weak lensing mass maps in order to
study
dark matter substructure in clusters of galaxies at high
redshift (z>0.5). Galaxy clusters are the largest virialized
structures in the universe, and are meaningful environments for
tests of cosmology. Mass substructure in clusters of galaxies is
important for several reasons: as a test of hierarchical Cold
Dark
Matter, as a way of reducing the scatter in the mass calibration of
clusters for
dark energy studies, and as environments for galaxy
and active galactic nuclei evolution.
Gravitational lensing is a powerful tool for measuring mass
in astronomical objects. According to General Relativity, very
massive objects bend the light of more distant objects around them,
thus distorting the shape of these background objects. In the weak
lensing regime, these shape distortions are small (few percent
level), and thus only detected as a systematic alignment about the
lensing cluster. Therefore, rigorous shape detection, extraction,
and statistical analysis are required to generate mass maps.
Starting with Hubble Space Telescope data, I carefully
correct for the HST’s Point Spread Function ellipticity pattern and
stack the images for each cluster. After extracting the stack data,
I perform a weak lensing analysis of the cluster. To characterize
the level of substructure, I apply a cluster finding variable
aperture filter. Finally, I fit an ensemble of NFW profiles to the
detected
matter peaks.
Advisors/Committee Members: Dell'Antonio, Ian (Director), Gaitskell, Richard (Reader), Koushiappas, Savvas (Reader).
Subjects/Keywords: dark matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huwe, P. M. (2013). Dark Matter Substructure in High Redshift Clusters of
Galaxies. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:320536/
Chicago Manual of Style (16th Edition):
Huwe, Paul M. “Dark Matter Substructure in High Redshift Clusters of
Galaxies.” 2013. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:320536/.
MLA Handbook (7th Edition):
Huwe, Paul M. “Dark Matter Substructure in High Redshift Clusters of
Galaxies.” 2013. Web. 03 Mar 2021.
Vancouver:
Huwe PM. Dark Matter Substructure in High Redshift Clusters of
Galaxies. [Internet] [Doctoral dissertation]. Brown University; 2013. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:320536/.
Council of Science Editors:
Huwe PM. Dark Matter Substructure in High Redshift Clusters of
Galaxies. [Doctoral Dissertation]. Brown University; 2013. Available from: https://repository.library.brown.edu/studio/item/bdr:320536/
6.
de Viveiros Souza Filho, Luiz Angelo.
Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments.
Degree: PhD, Physics, 2009, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:241/
► A wealth of evidence indicates that ~23% of the universe is composed of dark matter. For the past two decades, several experiments have attempted to…
(more)
▼ A wealth of evidence indicates that ~23% of the
universe is composed of
dark matter. For the past two decades,
several experiments have attempted to detect
dark matter directly
or indirectly. Nevertheless, its nature remains one of the most
elusive problems in fundamental physics today. XENON10 is a direct
detection experiment, using a liquid Xe Time Projection Chamber
(TPC) to search for
dark matter in the form of Weakly Interacting
Massive Particles (WIMPs). Particle interactions in the 15 kg
liquid Xe target generate scintillation (S1) and ionization (S2)
signals. WIMP (and neutron) interactions produce nuclear recoils.
The dominant backgrounds (gamma rays and beta particles) produce
electron recoils. The S2/S1 ratio is larger for electron recoils
than for nuclear recoils, allowing for the rejection of electron
recoil backgrounds with ~99.6% efficiency. XENON10 operated
underground at the Laboratori Nazionali Gran Sasso in Italy during
2006-2007. Analysis of its WIMP Search run of 58.6 live-days and
5.4 kg fiducial mass resulted at the time in the most sensitive
limits on the Spin-Independent WIMP-nucleon cross-section, setting
an upper limit of 8.8x10
-44 cm
2 for a WIMP mass of 100 GeV/c
2
(90% C.L.). The large scale experiment LUX (300 kg) is designed to
improve the sensitivity to WIMP interactions by two orders of
magnitude, and will be deployed in the Sanford Laboratory at the
Homestake Mine in 2009-2010. Next-generation Xe TPC detectors with
masses in the order of 1-10 tonnes are already in the design stage,
with planned deployment in the next ten years. In
dark matter
search experiments, backgrounds are the biggest factor limiting
sensitivity. This work presents a discussion of the use of liquid
Xe detectors in
dark matter experiments; details the construction
of background models through the use of Monte Carlo simulations;
identifies and characterizes the major sources of background;
explores how shielding and detector design affect the background
event rate; and explains the techniques used to reduce the effect
of backgrounds on the detector sensitivity.
Advisors/Committee Members: Gaitskell, Richard (director), Dell'Antonio, Ian (reader), Landsberg, Greg (reader).
Subjects/Keywords: Dark Matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
de Viveiros Souza Filho, L. A. (2009). Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:241/
Chicago Manual of Style (16th Edition):
de Viveiros Souza Filho, Luiz Angelo. “Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments.” 2009. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:241/.
MLA Handbook (7th Edition):
de Viveiros Souza Filho, Luiz Angelo. “Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments.” 2009. Web. 03 Mar 2021.
Vancouver:
de Viveiros Souza Filho LA. Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments. [Internet] [Doctoral dissertation]. Brown University; 2009. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:241/.
Council of Science Editors:
de Viveiros Souza Filho LA. Optimization of Signal versus Background in Liquid Xe
Detectors Used for Dark Matter Direct Detection Experiments. [Doctoral Dissertation]. Brown University; 2009. Available from: https://repository.library.brown.edu/studio/item/bdr:241/
7.
Malling, David Charles.
Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment.
Degree: PhD, Physics, 2014, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:386168/
► The dominant component of matter in the universe, referred to as dark matter, cannot be explained by the standard model of particle physics. A leading…
(more)
▼ The dominant component of
matter in the universe,
referred to as
dark matter, cannot be explained by the standard
model of particle physics. A leading candidate for
dark matter is
the weakly interacting massive particle (WIMP). The WIMP theory is
well motivated by several extensions of the standard model, and has
been tested directly in the laboratory over the last 30 years. The
Large Underground Xenon (LUX) experiment seeks to identify the
signatures of WIMP interactions with baryonic
matter. LUX measures
particle interactions at the keV level by the detection of
single-photon signals in a 250 kg Xe target mass. The LUX detector
inner fiducial region is the lowest measured background particle
detector in the world at keV energies, with background rates at the
level of 1E-3 counts/keV/kg/day. Low background rates are essential
for identifying WIMP interactions in the detector, which occur with
frequencies <1/kg/(5 years). LUX completed its first
low-background science run at the Sanford Underground Research
Facility in August 2013. WIMP search results are reported from an
85 live day analysis. The experiment places the tightest constraint
on WIMP spin-independent interaction cross-sections to date.
Results from LUX also exclude several potential
dark matter signal
claims from other direct detection experiments, for WIMP masses in
the range 6-15 GeV. The LUX result is the product of low detector
background rates and high photon signal collection efficiency.
Analysis of the first WIMP search data has provided direct
characterization of low-energy backgrounds in LUX. Measured
background rates were found to be in agreement with expectations
based on models of detector material radioactivity. The data also
provides the first measurements of intrinsic radioactive
contaminants in the detector, including short-lived cosmogenic Xe
radioisotopes. I will describe the LUX background model, detailing
work which was used in the design and early performance projections
of the LUX detector, as well as background measurements which
constrain and support the model.
Advisors/Committee Members: Gaitskell, Richard (Director), Savvas, Koushiappas (Reader), Cutts, David (Reader).
Subjects/Keywords: Dark matter
Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Malling, D. C. (2014). Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:386168/
Chicago Manual of Style (16th Edition):
Malling, David Charles. “Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment.” 2014. Doctoral Dissertation, Brown University. Accessed March 03, 2021.
https://repository.library.brown.edu/studio/item/bdr:386168/.
MLA Handbook (7th Edition):
Malling, David Charles. “Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment.” 2014. Web. 03 Mar 2021.
Vancouver:
Malling DC. Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment. [Internet] [Doctoral dissertation]. Brown University; 2014. [cited 2021 Mar 03].
Available from: https://repository.library.brown.edu/studio/item/bdr:386168/.
Council of Science Editors:
Malling DC. Measurement and Analysis of WIMP Detection Backgrounds, and
Characteri- zation and Performance of the Large Underground Xenon
Dark Matter Search Experiment. [Doctoral Dissertation]. Brown University; 2014. Available from: https://repository.library.brown.edu/studio/item/bdr:386168/

Queens University
8.
O'Dwyer, Eoin.
Radon Background Reduction in DEAP-1 and DEAP-3600
.
Degree: Physics, Engineering Physics and Astronomy, 2011, Queens University
URL: http://hdl.handle.net/1974/6267
► The Dark Matter Experiment with Liquid Argon Using Pulse Shape Discrim- ination (DEAP) is a dark matter experiment based in the SNOLAB facility in Sudbury,…
(more)
▼ The Dark Matter Experiment with Liquid Argon Using Pulse Shape Discrim-
ination (DEAP) is a dark matter experiment based in the SNOLAB facility in
Sudbury, Ontario. Its aim is to detect WIMPs, Weakly Interacting Massive Par-
ticles, that may make up the missing component of the matter in our universe by
the scintillation of liquid argon from nuclear recoils. A 7 kg prototype, DEAP-1,
is currently in operation with work underway to scale up to a 1 tonne detector,
DEAP-3600, by 2012. For DEAP-3600 to be a competitive dark matter search,
a limit of 0.2 fiducial surface alpha events is required in the energy region of interest for three years of run time,
or 150 total surface events. Of particular concern to the DEAP experiment is 222Rn and its daughter prod-
ucts, as the alpha decays of these isotopes may create events in the detector that
mimic a WIMP signature. The first half of this thesis concerns the testing and suc-
cessful use of an activated carbon trap to eliminate 222Rn from the argon gas source
in DEAP-1. The Carbo-Act F2/F3 grain activated carbon brand was tested as a
potential ultra-low activity candidate for a DEAP-3600 filtration system and was
found to have an upper limit for its 222Rn emanation rate of 284 atoms/day/kg.
A temperature swing system is proposed. If operated at 110 K, an upper limit of
five atoms of 222Rn can be expected to enter the detector from the trap.
An indirect relationship between the number of low energy nuclear recoil events
in the DEAP WIMP region of interest and the number of radon alpha decays was
found. The ratio between the low energy events in the WIMP region of interest and
the high energy alphas was found to be 0.18 ± 0.03 in the detector.
From this, the upper limit of the contribution from the proposed radon trap to the WIMP
background in DEAP-3600 will be be ten events for three years of run time, which
is within acceptable limits.
Subjects/Keywords: dark matter
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MLA ·
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CSE |
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
O'Dwyer, E. (2011). Radon Background Reduction in DEAP-1 and DEAP-3600
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/6267
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
O'Dwyer, Eoin. “Radon Background Reduction in DEAP-1 and DEAP-3600
.” 2011. Thesis, Queens University. Accessed March 03, 2021.
http://hdl.handle.net/1974/6267.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
O'Dwyer, Eoin. “Radon Background Reduction in DEAP-1 and DEAP-3600
.” 2011. Web. 03 Mar 2021.
Vancouver:
O'Dwyer E. Radon Background Reduction in DEAP-1 and DEAP-3600
. [Internet] [Thesis]. Queens University; 2011. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/1974/6267.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
O'Dwyer E. Radon Background Reduction in DEAP-1 and DEAP-3600
. [Thesis]. Queens University; 2011. Available from: http://hdl.handle.net/1974/6267
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University
9.
Kumar, Naresh.
Dark Aspects Of Cosmology.
Degree: PhD, Physics, 2012, Cornell University
URL: http://hdl.handle.net/1813/31115
► This thesis investigates aspects of dark matter and dark energy and constraints that can be imposed on them from current and future observations. Specifically, we…
(more)
▼ This thesis investigates aspects of
dark matter and
dark energy and constraints that can be imposed on them from current and future observations. Specifically, we first study the idea that the observed acceleration of the Universe could be due to the gravitational backreaction of perturbations on superhorizon scales. We show that this does not work for the case of a cosmological model containing baryonic
matter, cold
dark matter and a scalar field. Next, assuming the presence of
dark energy and
dark matter, we study the gravitational lensing effects of large scale structures on luminosity distances of sources. Standard candle sources such as supernovae have been used to measure the
dark energy content of the Universe, and gravitational lensing is a source of systematic error in these measurements. We investigate the effects of large scale structures like voids and smaller halos using Monte Carlo simulations.
Advisors/Committee Members: Flanagan, Eanna E (chair), Thom-Levy, Julia (committee member), Wasserman, Ira M (committee member).
Subjects/Keywords: Dark matter; Dark energy; Cosmology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kumar, N. (2012). Dark Aspects Of Cosmology. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/31115
Chicago Manual of Style (16th Edition):
Kumar, Naresh. “Dark Aspects Of Cosmology.” 2012. Doctoral Dissertation, Cornell University. Accessed March 03, 2021.
http://hdl.handle.net/1813/31115.
MLA Handbook (7th Edition):
Kumar, Naresh. “Dark Aspects Of Cosmology.” 2012. Web. 03 Mar 2021.
Vancouver:
Kumar N. Dark Aspects Of Cosmology. [Internet] [Doctoral dissertation]. Cornell University; 2012. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/1813/31115.
Council of Science Editors:
Kumar N. Dark Aspects Of Cosmology. [Doctoral Dissertation]. Cornell University; 2012. Available from: http://hdl.handle.net/1813/31115

University of Waterloo
10.
Grossauer, Jonathan.
Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation.
Degree: 2012, University of Waterloo
URL: http://hdl.handle.net/10012/7062
► Using data from the Next Generation Virgo Cluster Survey and high-resolution simulations of Virgo cluster-like halos, we determine the stellar-to-halo mass relation (SHMR) for subhalos,…
(more)
▼ Using data from the Next Generation Virgo Cluster Survey and high-resolution simulations of Virgo cluster-like halos, we determine the stellar-to-halo mass relation (SHMR) for subhalos, using the technique of abundance matching. The subhalo SHMR differs markedly from its field galaxy counterpart, regardless of how the subhalo mass is defined (mass at z = 0, mass at infall, or maximum mass while in the field). The slope of the relation at low mass (M⋆<1010 Msun) is in all cases steeper than the same for the field. We find conflicting indicators of whether this difference in slope indicates an increasing or decreasing dark-to-stellar ratio; further modelling is required to reach a definitive conclusion. We also find evidence for the existence of a measurable age gradient in velocity, such that older subhalos have lower velocities than their younger peers. This opens the possibility that good quality redshifts of the lower mass galaxies of the Virgo cluster might provide additional constraints on the SHMR at high redshift and its evolution. Finally, we investigate the degree to which mergers, particularly major mergers, cause mixing of old and new material in halos, which has implications for the robustness of any implied radial age gradient. We find only a slight increase in mixing for major mergers over minor mergers, and little evidence for any large amount of mixing being induced by mergers of any ratio.
Subjects/Keywords: Dark Matter; Galaxies: Dark Matter Halos
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Grossauer, J. (2012). Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7062
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Grossauer, Jonathan. “Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation.” 2012. Thesis, University of Waterloo. Accessed March 03, 2021.
http://hdl.handle.net/10012/7062.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Grossauer, Jonathan. “Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation.” 2012. Web. 03 Mar 2021.
Vancouver:
Grossauer J. Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation. [Internet] [Thesis]. University of Waterloo; 2012. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/10012/7062.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Grossauer J. Abundance Matching with the Galaxies of the Virgo Cluster and the Stellar-to-Halo Mass Relation. [Thesis]. University of Waterloo; 2012. Available from: http://hdl.handle.net/10012/7062
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queens University
11.
Kamaha, Alvine.
Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
Degree: Physics, Engineering Physics and Astronomy, 2015, Queens University
URL: http://hdl.handle.net/1974/12780
► The final results of the PICASSO experiment, with 409 kg days of exposure collected from November 2012 to January 2014, have yielded new limits for…
(more)
▼ The final results of the PICASSO experiment, with 409 kg days of exposure collected from November 2012 to January 2014, have yielded new limits for Spin-Dependent and Spin-Independent Dark Matter interactions.\\
The data collected and the various backgrounds were assiduously studied using Monte Carlo simulations and a new set of sophisticated analysis techniques including the wavelet analysis presented in this thesis. In general, a good suppression of most backgrounds was attained. The neutron background event rate was reduced to about a factor of 10 compared to the previous phase of the experiment. Electronic and acoustic noise events were thoroughly suppressed. A new class of ``mystery events'' were removed as well. All that remained was the irreducible alpha background.\\
No signal consistent with a WIMP Dark Matter hypothesis was observed. Consequently, an exclusion curve was obtained with a minimum limit at {90%} C.L. of {σχ pSD =0.0228} pb at a WIMP mass of 20 GeV/c2 in the Spin-Dependent sector. By combining results from 2012 and the current results, an improved constraint of {σχ pSD}(90{%} C.L.) {=0.0188} pb at 20 GeV/c2 was placed on the Dark Matter interaction with protons in the Fluorine nuclei used in the detectors.\\
In addition, the new limits on WIMP-proton interactions in the Spin Independent sector exclude the DAMA/LIBRA results (at {90%} C.L.) for low masses below 12 GeV/c2 and further constrain the published CRESST and CDMS Si discovery regions at low WIMP masses.
Subjects/Keywords: Dark Matter searches
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kamaha, A. (2015). Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
(Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/12780
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kamaha, Alvine. “Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
” 2015. Thesis, Queens University. Accessed March 03, 2021.
http://hdl.handle.net/1974/12780.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kamaha, Alvine. “Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
” 2015. Web. 03 Mar 2021.
Vancouver:
Kamaha A. Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
[Internet] [Thesis]. Queens University; 2015. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/1974/12780.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kamaha A. Improved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.
[Thesis]. Queens University; 2015. Available from: http://hdl.handle.net/1974/12780
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queens University
12.
Fox, Joseph.
Detector Development and Test Facility Commissioning for SuperCDMS
.
Degree: Physics, Engineering Physics and Astronomy, 2011, Queens University
URL: http://hdl.handle.net/1974/6537
► SuperCDMS, the next stage of the Cryogenic Dark Matter Search (CDMS), uses cylindrical germa- nium crystals as particle detectors to measure phonon and ionization signals…
(more)
▼ SuperCDMS, the next stage of the Cryogenic Dark Matter Search (CDMS), uses cylindrical germa-
nium crystals as particle detectors to measure phonon and ionization signals resulting from particle
interactions. The aim of CDMS is to identify and measure interactions from dark matter particles
(WIMPs). Phonons produced during a particle interaction are absorbed by sensors on the detector
surface and are measured through the change in the sensors' temperature dependent resistance.
Electrodes on the detector surface create an electric eld causing charges released during an inter-
action to drift through the detector and produce an ionization signal. Surface events, which are
interactions that occur within a few m from the electrodes, cause a reduced ionization signal due
to di usion of some of the initially hot charge carriers into the electrode. Because the ability of
CDMS to discriminate between a WIMP interaction and background radiation is based on the ratio
of phonon to ionization energies, surface events cause a signal similar to a WIMP interaction and
are currently the largest source of background.
A detector test facility at Queen's University has been commissioned to characterize detectors
and test new detector technology. Multiple detectors have been characterized and many tungsten
samples have been measured. Two sets of experiments were performed to test new detector designs.
To possibly reduce surface events, an insulating layer was deposited on a germanium detector be-
neath the electrode to prevent back di usion of charge into the electrode. To possibly simplify the
phonon sensor production process, di erent cryogenic glues were used to attach silicon wafers with
a tungsten lm to the crystal surface and phonon propagation through these glues was measured.
The most e ective cryogenic glue for coupling tungsten samples to CDMS detectors was found to
be Araldite epoxy. Both experiments were successful at measuring interactions. Energy calibrations
were performed on both charge and phonon sensors. Further research is required to determine the
success of reducing surface events with an insulating layer.
Subjects/Keywords: Dark Matter
;
CDMS
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fox, J. (2011). Detector Development and Test Facility Commissioning for SuperCDMS
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/6537
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Fox, Joseph. “Detector Development and Test Facility Commissioning for SuperCDMS
.” 2011. Thesis, Queens University. Accessed March 03, 2021.
http://hdl.handle.net/1974/6537.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Fox, Joseph. “Detector Development and Test Facility Commissioning for SuperCDMS
.” 2011. Web. 03 Mar 2021.
Vancouver:
Fox J. Detector Development and Test Facility Commissioning for SuperCDMS
. [Internet] [Thesis]. Queens University; 2011. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/1974/6537.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Fox J. Detector Development and Test Facility Commissioning for SuperCDMS
. [Thesis]. Queens University; 2011. Available from: http://hdl.handle.net/1974/6537
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Hong Kong University of Science and Technology
13.
Chui, Kris On-Yan.
A survey of dark matter physics.
Degree: 2016, Hong Kong University of Science and Technology
URL: http://repository.ust.hk/ir/Record/1783.1-87537
;
https://doi.org/10.14711/thesis-b1585217
;
http://repository.ust.hk/ir/bitstream/1783.1-87537/1/th_redirect.html
► A survey has been conducted on the subject of dark matter. This work has been carried out to be a foundation for future original theoretical…
(more)
▼ A survey has been conducted on the subject of dark matter. This work has been carried out to be a foundation for future original theoretical work. In this survey, we will examine the (1) evidence for dark matter, (2) dark matter candidates, and (3) the global detection of dark matter currently being conducted. An emphasis will be placed on the recent findings of the Fermi-LAT collaboration, based on the Fermi Large Area Telescope (LAT) observations of the gamma-ray excess originating in the Milky Way’s Galactic Center (GC).
Subjects/Keywords: Dark matter (Astronomy)
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chui, K. O. (2016). A survey of dark matter physics. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-87537 ; https://doi.org/10.14711/thesis-b1585217 ; http://repository.ust.hk/ir/bitstream/1783.1-87537/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chui, Kris On-Yan. “A survey of dark matter physics.” 2016. Thesis, Hong Kong University of Science and Technology. Accessed March 03, 2021.
http://repository.ust.hk/ir/Record/1783.1-87537 ; https://doi.org/10.14711/thesis-b1585217 ; http://repository.ust.hk/ir/bitstream/1783.1-87537/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chui, Kris On-Yan. “A survey of dark matter physics.” 2016. Web. 03 Mar 2021.
Vancouver:
Chui KO. A survey of dark matter physics. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2016. [cited 2021 Mar 03].
Available from: http://repository.ust.hk/ir/Record/1783.1-87537 ; https://doi.org/10.14711/thesis-b1585217 ; http://repository.ust.hk/ir/bitstream/1783.1-87537/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chui KO. A survey of dark matter physics. [Thesis]. Hong Kong University of Science and Technology; 2016. Available from: http://repository.ust.hk/ir/Record/1783.1-87537 ; https://doi.org/10.14711/thesis-b1585217 ; http://repository.ust.hk/ir/bitstream/1783.1-87537/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Princeton University
14.
Zhu, Chengliang.
Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
.
Degree: PhD, 2018, Princeton University
URL: http://arks.princeton.edu/ark:/88435/dsp01qj72p990h
► Since the secondary scintillation signals of dual phase Time Projection Chamber (TPC) detectors are produced through noble gas electroluminescence, a comprehensive understanding of electroluminescence is…
(more)
▼ Since the secondary scintillation signals of dual phase Time Projection Chamber (TPC) detectors are produced through noble gas electroluminescence, a comprehensive understanding of electroluminescence is essential for the design and simulation of a future detector.
In this dissertation, I determine a fundamental property, the field dependence of light yield, of argon electroluminescence, using data from DarkSide-50 (DS-50), a detector designed for direct detection of
dark matter.
The analysis requires a good understanding of the detector geometry in the secondary scintillation region of DS-50. However, deformations of the detector components are implied by the data, and they cannot be directly measured. I thus determine the field dependence under two hypotheses for the deformations. The results obtained by applying the different hypotheses have systematic differences, but are close to each other and agree with the results from other studies.
The results from this study are applied to predict the secondary scintillation light yield and its stability for different design schemes for DarkSide-20k (DS-20k), the next generation of DarkSide detector.
Advisors/Committee Members: Meyers, Peter D (advisor).
Subjects/Keywords: dark matter;
electroluminescence
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhu, C. (2018). Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
. (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01qj72p990h
Chicago Manual of Style (16th Edition):
Zhu, Chengliang. “Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
.” 2018. Doctoral Dissertation, Princeton University. Accessed March 03, 2021.
http://arks.princeton.edu/ark:/88435/dsp01qj72p990h.
MLA Handbook (7th Edition):
Zhu, Chengliang. “Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
.” 2018. Web. 03 Mar 2021.
Vancouver:
Zhu C. Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
. [Internet] [Doctoral dissertation]. Princeton University; 2018. [cited 2021 Mar 03].
Available from: http://arks.princeton.edu/ark:/88435/dsp01qj72p990h.
Council of Science Editors:
Zhu C. Study of Argon Electroluminescence Light Yield using Data from DarkSide-50
. [Doctoral Dissertation]. Princeton University; 2018. Available from: http://arks.princeton.edu/ark:/88435/dsp01qj72p990h

University of Minnesota
15.
Young, Anthony.
Post-merger configurations of gravitationally bound dark matter systems.
Degree: PhD, Astrophysics, 2018, University of Minnesota
URL: http://hdl.handle.net/11299/199029
► During the merger of two galaxies, the resulting system undergoes violent relaxation and seeks stable equilibrium. However, the details of this evolution are not fully…
(more)
▼ During the merger of two galaxies, the resulting system undergoes violent relaxation and seeks stable equilibrium. However, the details of this evolution are not fully understood. Before we address evolution, we examine two different classes of models that describe equilibrium, or steady-state dark matter halos, in order to look for clues regarding the dynamical state of the halo. Both classes exhibit non-monotonic changes in their density profile slopes which we call oscillations for short. We analyze these two unrelated classes separately. Class 1 consists of systems that have density oscillations and that are defined through their distribution function f(E), or differential energy distribution N(E), such as isothermal spheres, King profiles, or DARKexp, a theoretically derived model for relaxed collisionless systems. Systems defined through f(E) or N(E) generally have density slope oscillations. We then proceed to investigate the physical basis for these oscillations and the relationship with the dynamical state of the halo. Using Illustris simulation, we probe two physically related processes, mixing and relaxation. Though the two are driven by the same dynamics – global time-varying potential for the energy, and torques caused by asymmetries for angular momentum – we measure them differently. We define mixing as the redistribution of energy and angular momentum between particles of the two merging galaxies. We assess the degree of mixing as the difference between the shapes of their energy distributions, N(E)s, and their angular momentum distributions, N(L2)s. We find that the difference is decreasing with time, indicating mixing. To measure relaxation, we compare N(E) of the newly merged system to N(E) of a theoretical prediction for relaxed collisionless systems, DARKexp, and witness the system becoming more relaxed, in the sense that N(E) approaches DARKexp N(E). Because the dynamics driving mixing and relaxation are the same, the timescale is similar for both. We measure two sequential timescales: a rapid, 1 Gyr phase after the initial merger, during which the difference in N(E) of the two merging halos decreases by ∼ 80%, followed by a slow phase, when the difference decreases by ∼ 50% over ∼ 8.5 Gyrs. This is a direct measurement of the relaxation timescale.
Subjects/Keywords: Dark matter halos
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Young, A. (2018). Post-merger configurations of gravitationally bound dark matter systems. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/199029
Chicago Manual of Style (16th Edition):
Young, Anthony. “Post-merger configurations of gravitationally bound dark matter systems.” 2018. Doctoral Dissertation, University of Minnesota. Accessed March 03, 2021.
http://hdl.handle.net/11299/199029.
MLA Handbook (7th Edition):
Young, Anthony. “Post-merger configurations of gravitationally bound dark matter systems.” 2018. Web. 03 Mar 2021.
Vancouver:
Young A. Post-merger configurations of gravitationally bound dark matter systems. [Internet] [Doctoral dissertation]. University of Minnesota; 2018. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/11299/199029.
Council of Science Editors:
Young A. Post-merger configurations of gravitationally bound dark matter systems. [Doctoral Dissertation]. University of Minnesota; 2018. Available from: http://hdl.handle.net/11299/199029

Universitat de Valencia
16.
Boucenna, Mohamed Sofiane.
Neutrino physics and dark matter
.
Degree: 2014, Universitat de Valencia
URL: http://hdl.handle.net/10550/39768
► El descubrimiento de las oscilaciones de neutrinos y la evidencia de la existencia de materia oscura, demuenstran la necesidad de una nueva f ́ısica m…
(more)
▼ El descubrimiento de las oscilaciones de neutrinos y la evidencia de la existencia de materia oscura, demuenstran la necesidad de una nueva f ́ısica m ́as all ́a del modelo est ́andar (SM). Sin embargo, la naturaleza detallada de la nueva f ́ısica sigue siendo dif ́ıcil de alcanzar. Por un lado, se desconoce el mecanismo responsable de generaci ́on de masa de los neutrinos y su estructura de sabor. Por lo tanto, la naturaleza de los neutrinos, su masa y par ́ametros de mezcla son todos impredichos en el SM. Por otro, la naturaleza de la materia oscura (DM) constituye uno de los problemas mas end ́emicos en la cosmolog ́ıa desde d ́ecadas, aunque recientemente algunos experimentos de detecci ́on directa e indirecta de DM est ́an mostrando indicios que dan esperanza de una detecci ́on inminente.
La vinculaci ́on entre la generaci ́on de masa del neutrino y la naturaleza de la materia oscura, en un unico marco, es te ́oricamente atractivo, y puede generar nuevas ideas sobre ambas cuestiones. La idea de la unificaci ́on en s ́ı, o como Feynman sol ́ıa llamarla amalgamaci ́on, es fundamental para la f ́ısica, y en general para cualquier disciplina cient ́ıfica. Unificar es obtener nuevos conocimientos mediante la s ́ıntesis y generalizaci ́on de los conocimientos.
Esta tesis est ́a dedicada a la interacci ́on entre la f ́ısica de neutrinos y la materia oscura. Especialmente en el desarrollo y la comprensi ́on de los modelos en los que la din ́amica de la materia oscura y los neutrinos est ́an relacionados.
Mediante la conexi ́on de la materia oscura con los neutrinos, es posible obtener informaci ́on directa e indirecta sobre la nueva f ́ısica. De hecho, los neutrinos ofrecen una manifestaci ́on notable de esta nueva f ́ısica y varios experimentos nos proporcionan datos precisos sobre sus mezclas y masas. Estos datos revelan un fuerte contraste con el caso conocido de los quarks. Por las escalas de energ ́ıa involucradas en el problema y la precisi ́on de estas mediciones, la
f ́ısica de neutrinos ofrece una visi ́on tentadora de uno de los problemas m ́as
profundos y duraderos del SM, a saber, el problema de sabor.
Advisors/Committee Members: Furtado Valle, José Wagner (advisor).
Subjects/Keywords: neutrinos;
dark matter
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Boucenna, M. S. (2014). Neutrino physics and dark matter
. (Doctoral Dissertation). Universitat de Valencia. Retrieved from http://hdl.handle.net/10550/39768
Chicago Manual of Style (16th Edition):
Boucenna, Mohamed Sofiane. “Neutrino physics and dark matter
.” 2014. Doctoral Dissertation, Universitat de Valencia. Accessed March 03, 2021.
http://hdl.handle.net/10550/39768.
MLA Handbook (7th Edition):
Boucenna, Mohamed Sofiane. “Neutrino physics and dark matter
.” 2014. Web. 03 Mar 2021.
Vancouver:
Boucenna MS. Neutrino physics and dark matter
. [Internet] [Doctoral dissertation]. Universitat de Valencia; 2014. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/10550/39768.
Council of Science Editors:
Boucenna MS. Neutrino physics and dark matter
. [Doctoral Dissertation]. Universitat de Valencia; 2014. Available from: http://hdl.handle.net/10550/39768

University of New South Wales
17.
Stadnik, Yevgeny.
Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena.
Degree: Physics, 2017, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/57545
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:43638/SOURCE02?view=true
► Astrophysical observations indicate that there is five times more dark matter - an 'invisible' form of matter whose identities and properties still remain shrouded in…
(more)
▼ Astrophysical observations indicate that there is five times more
dark matter - an 'invisible' form of
matter whose identities and properties still remain shrouded in mystery - in the Universe than the ordinary 'visible'
matter that makes up stars, planets, dust and interstellar gases. Conventional schemes for the direct detection of
dark matter involve processes (such as collisions with, absorption by or inter-conversion with ordinary
matter) which are either quartic (g
4) or quadratic (g
2) in an underlying interaction constant g. In this thesis, I explore the possibility of searching for new effects of
dark matter that are linear in g. Searching for linear effects of
dark matter may provide an enormous advantage over conventional schemes, since the interaction constant g is very small, g << 1. Indeed, by investigating linear effects, I have derived new limits on certain interactions of
dark matter with ordinary
matter that have improved on previous limits by up to 15 orders of magnitude, as well as the first ever limits on several other interactions. Linear effects may arise for low-mass (sub-eV/c
2), bosonic (integral spin)
dark matter particles. Such particles can be produced in the early Universe with negligible kinetic energy and form an oscillating classical field, φ(t) = φ
0*\cos(m_φ*c
2*t/\hbar). Alternatively, these low-mass bosons may also form topological defects, such as domain walls, strings and monopoles. The interactions of these oscillating fields or topological defects with ordinary
matter can produce effects that are linear in the interaction constant g. Possible linear effects of
dark matter include the induction of a cosmological evolution of the fundamental constants (such as the electromagnetic fine-structure constant α and the particle masses), which may be sought for with atomic clock spectroscopy and laser interferometry measurements in the laboratory, as well as astrophysical big bang nucleosynthesis measurements. Other linear effects of
dark matter include spin-precession effects and oscillating spin-gravity couplings, and parity and time-reversal-invariance violating effects: oscillating nuclear Schiff and magnetic quadrupole moments, oscillating atomic and nuclear anapole moments, and oscillating atomic and molecular electric dipole moments; these effects may be sought for with a variety of magnetometric techniques.
Advisors/Committee Members: Flambaum, Victor, Physics, Faculty of Science, UNSW.
Subjects/Keywords: Astrophysics; Dark matter
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Stadnik, Y. (2017). Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/57545 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:43638/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Stadnik, Yevgeny. “Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena.” 2017. Doctoral Dissertation, University of New South Wales. Accessed March 03, 2021.
http://handle.unsw.edu.au/1959.4/57545 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:43638/SOURCE02?view=true.
MLA Handbook (7th Edition):
Stadnik, Yevgeny. “Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena.” 2017. Web. 03 Mar 2021.
Vancouver:
Stadnik Y. Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena. [Internet] [Doctoral dissertation]. University of New South Wales; 2017. [cited 2021 Mar 03].
Available from: http://handle.unsw.edu.au/1959.4/57545 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:43638/SOURCE02?view=true.
Council of Science Editors:
Stadnik Y. Manifestations of Dark Matter and Variations of the Fundamental Constants of Nature in Atoms and Astrophysical Phenomena. [Doctoral Dissertation]. University of New South Wales; 2017. Available from: http://handle.unsw.edu.au/1959.4/57545 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:43638/SOURCE02?view=true
18.
Carrillo Monteverde, Alba Leticia.
Dark Matter direct detection from a model with spin-2 mediators.
Degree: PhD, 2020, University of Sussex
URL: http://sro.sussex.ac.uk/id/eprint/92837/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814083
► Dark Matter (DM) and its nature is one of the most interesting problems in modern physics. DM constitutes the 27% of the total content of…
(more)
▼ Dark Matter (DM) and its nature is one of the most interesting problems in modern physics. DM constitutes the 27% of the total content of the Universe and evidence of its existence have been accumulated at diferent scales thanks to its gravitational infuence on ordinary matter. One of the most interesting proposals to study this problem is to assume that DM is made of particles. We study models where a massive spin-two resonance acts as the mediator between Dark Matter (DM) and the SM particles. The interaction of DM and SM is through the energy-momentum tensor and we explore the scenarios where DM is a fermion, a scalar and a vector field. We identify the effective interactions when the mediator is interated out, and match them to the gravitational form factors in order to study the DM-nucleon scattering that will be helpful in the phenomenological analysis. Up to this day, only gravitational efects of DM have been observed but we hope to obtain information that will help us to identify its nature through these three different approaches: direct detection searches, indirect detection techniques and production at colliders. In the context of this work, we obtain the limits on the parameter space of the Gravity Mediated Dark Matter model using the relic density conditions, direct detection bounds and collider searches for the spin-two mediator.
Subjects/Keywords: QB0791.3 Dark matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Carrillo Monteverde, A. L. (2020). Dark Matter direct detection from a model with spin-2 mediators. (Doctoral Dissertation). University of Sussex. Retrieved from http://sro.sussex.ac.uk/id/eprint/92837/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814083
Chicago Manual of Style (16th Edition):
Carrillo Monteverde, Alba Leticia. “Dark Matter direct detection from a model with spin-2 mediators.” 2020. Doctoral Dissertation, University of Sussex. Accessed March 03, 2021.
http://sro.sussex.ac.uk/id/eprint/92837/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814083.
MLA Handbook (7th Edition):
Carrillo Monteverde, Alba Leticia. “Dark Matter direct detection from a model with spin-2 mediators.” 2020. Web. 03 Mar 2021.
Vancouver:
Carrillo Monteverde AL. Dark Matter direct detection from a model with spin-2 mediators. [Internet] [Doctoral dissertation]. University of Sussex; 2020. [cited 2021 Mar 03].
Available from: http://sro.sussex.ac.uk/id/eprint/92837/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814083.
Council of Science Editors:
Carrillo Monteverde AL. Dark Matter direct detection from a model with spin-2 mediators. [Doctoral Dissertation]. University of Sussex; 2020. Available from: http://sro.sussex.ac.uk/id/eprint/92837/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814083

University of Illinois – Urbana-Champaign
19.
Chue, Chun Yin Ricky.
The structure and spatial distribution of dark matter halos.
Degree: PhD, Astronomy, 2018, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/102875
► This is a study of how the distribution and properties of dark matter halos can be utilized as probes of fundamental questions in modern cosmology.…
(more)
▼ This is a study of how the distribution and properties of
dark matter halos can be utilized as probes of fundamental questions in modern cosmology. Spatial clustering of
dark matter halo carry a wealth of information regarding its evolution history and environment. In particular, I study halo assembly bias, which refers to the assembly history dependence of spatial clustering for
dark matter halos at fixed mass, using observational and cosmological simulation data. Understanding and modeling assembly bias provides insight into the context of hierarchical structure formation theory. Apart from spatial clustering I also study shapes of
dark matter halos and how to measure them using three-point galaxy statistics, which itself serves as an astrophysical constraint on properties of
dark matter.
Advisors/Committee Members: Dalal, Neal (advisor), Fields, Brian (Committee Chair), Ricker, Paul (committee member), Kemball, Athol (committee member).
Subjects/Keywords: Dark matter halo
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chue, C. Y. R. (2018). The structure and spatial distribution of dark matter halos. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/102875
Chicago Manual of Style (16th Edition):
Chue, Chun Yin Ricky. “The structure and spatial distribution of dark matter halos.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 03, 2021.
http://hdl.handle.net/2142/102875.
MLA Handbook (7th Edition):
Chue, Chun Yin Ricky. “The structure and spatial distribution of dark matter halos.” 2018. Web. 03 Mar 2021.
Vancouver:
Chue CYR. The structure and spatial distribution of dark matter halos. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/2142/102875.
Council of Science Editors:
Chue CYR. The structure and spatial distribution of dark matter halos. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/102875

UCLA
20.
Georgescu, Andreea.
Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments.
Degree: Physics, 2015, UCLA
URL: http://www.escholarship.org/uc/item/78g1p1p1
► We reexamine the current direct dark matter (DM) detection data for several types of DM candidates, both assuming the Standard Halo Model (SHM) and in…
(more)
▼ We reexamine the current direct dark matter (DM) detection data for several types of DM candidates, both assuming the Standard Halo Model (SHM) and in a halo-independent manner. We consider the potential signals for light WIMPs that have appeared in three direct detection searches: DAMA, CDMS-II-Si, and CoGeNT, and we analyze their compatibility with the null results of other direct detection experiments.We first consider light WIMPs with exothermic scattering with nuclei (exoDM). Exothermic interactions favor light targets, thus reducing the importance of upper limits derived from Xe targets, the most restrictive of which is at present the LUX limit. In our SHM analysis the CDMS-II-Si and CoGeNT regions become allowed by these bounds, however the SuperCDMS limit rejects both regions for exoDM with isospin-conserving couplings. An isospin-violating coupling of the exoDM, in particular one with a neutron to proton coupling ratio of -0.8 (which we call "Ge-phobic"), maximally reduces the DM coupling to Ge and allows the CDMS-II-Si region to become compatible with all upper bounds. This is also clearly shown in our halo-independent analysis.Next, we extend and correct a recently proposed maximum-likelihood halo-independent method to analyze unbinned direct DM detection data. Instead of the recoil energy as an independent variable, we use the minimum speed a DM particle must have to impart a given recoil energy to a nucleus. This has the advantage of allowing us to apply the method to any type of target composition and interaction, e.g. with general momentum and velocity dependence, and with elastic or inelastic scattering. We prove the method and provide a rigorous statistical interpretation of the results. As first applications, we find that for dark matter particles with elastic spin-independent interactions and neutron to proton coupling ratio fn/fp=-0.7 ("Xe-phobic", which reduces maximally the coupling to Xe), the WIMP interpretation of the signal observed by CDMS-II-Si is compatible with the constraints imposed by all other experiments with null results. We also find a similar compatibility for exothermic inelastic spin-independent interactions with fn/fp=-0.8.Finally, we reexamine the interpretation of the annual modulation signal observed by the DAMA experiment as due to WIMPs with a spin-dependent coupling mostly to protons. We consider both axial-vector and pseudo-scalar couplings, and elastic as well as endothermic and exothermic inelastic scattering. We conclude that the DAMA signal is in strong tension with null results of other direct detection experiments, particularly PICASSO and KIMS.
Subjects/Keywords: Physics; dark matter direct detection; dark matter experiments; dark matter theory
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Georgescu, A. (2015). Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/78g1p1p1
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Georgescu, Andreea. “Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments.” 2015. Thesis, UCLA. Accessed March 03, 2021.
http://www.escholarship.org/uc/item/78g1p1p1.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Georgescu, Andreea. “Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments.” 2015. Web. 03 Mar 2021.
Vancouver:
Georgescu A. Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments. [Internet] [Thesis]. UCLA; 2015. [cited 2021 Mar 03].
Available from: http://www.escholarship.org/uc/item/78g1p1p1.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Georgescu A. Tests of WIMP Dark Matter Candidates with Direct Dark Matter Detection Experiments. [Thesis]. UCLA; 2015. Available from: http://www.escholarship.org/uc/item/78g1p1p1
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Urbana-Champaign
21.
Alizadeh, Esfandiar.
Topics in cosmology: structure formation, dark energy and recombination.
Degree: PhD, 0240, 2011, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/26155
► The field of theoretical cosmology consists of numerous, inter-related branches, whose ambitious goal is to uncover the history of the universe from its beginning…
(more)
▼ The field of theoretical cosmology consists of numerous, inter-related branches, whose ambitious goal is to uncover the history of the universe from its beginning to its future. Achieving this, no doubt, requires a deep understanding of many areas of physics. In this thesis I touch upon a few of these areas in which I worked during my PhD studies.
Chapter~(\ref{ch:accretion}) describes our work in finding the accretion and merger history of
dark matter halos.
Dark matter halos are the collapsed
dark matter structures in the late time evolution of the universe, whose existence is vital for the formation of galaxies in the Universe as they act as the potential wells where normal
matter (collectively called Baryons) can accumulate, cool, and form stars. It is then no surprise that the properties of galaxies depends on the properties of the
dark matter halo in which it resides, including its merger history, i.e. the number of times it merged with other halos. Even though these merger rates can be calculated theoretically for infinitesimal time steps, in order to find the merger history over an extended period of time one had to use either Monte-Carlo simulations to build up the total rates of merging and accreting from the infinitesimal rates or use N-body simulations. In chapter~(\ref{ch:accretion}) we show how we used random walk formalism to write down an {\it analytical} (integral) equation for the merger history of halos. We have solved this equation numerically and find very good agreement with Monte-Carlo simulations. This work can be used in theories of galaxy formation and evolution.
We then switch from the overdense regions of the Universe, halos, to the underdense ones, voids. These structures have not attracted as much attention from cosmologists as their overdense counterparts in probing the cosmological models. We show here that the shapes of voids as a probe can be of use for future surveys to pin down the equation of state of the
dark energy, i.e. the ratio of its pressure to its energy density. As first approximation, voids can be considered to be ellipsoids whose axis ratio evolution depends on the cosmological parameters. This, together with the fact that the initial distribution of the axis ratios is known (because the intial density field is Gaussian) can be used to infer the equation of state of the
dark energy statistically from the observation of voids at different redshifts and with different sizes. The standard method of Fisher matrices is then used to forecast how well a future survey can measure the equation of state. We find promising results with constraints coming from void ellipticity measurements comparable to those of other standard methods.
Chapter~(\ref{ch:H2}) goes farther back in the history of the Universe. During the {\it recombination} era, when the Universe was around a thousandth of its present size, it became cool enough that free electrons got captured by free protons to make hydrogen atoms. Consequently, the Thompson scattering of photons off of free…
Advisors/Committee Members: Wandelt, Benjamin D. (advisor), Fields, Brian D. (Committee Chair), Wandelt, Benjamin D. (committee member), Thaler, Jonathan J. (committee member), Weissman, Michael B. (committee member).
Subjects/Keywords: Cosmology; Dark Matter Halos; Dark Energy; Recombination
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alizadeh, E. (2011). Topics in cosmology: structure formation, dark energy and recombination. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/26155
Chicago Manual of Style (16th Edition):
Alizadeh, Esfandiar. “Topics in cosmology: structure formation, dark energy and recombination.” 2011. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 03, 2021.
http://hdl.handle.net/2142/26155.
MLA Handbook (7th Edition):
Alizadeh, Esfandiar. “Topics in cosmology: structure formation, dark energy and recombination.” 2011. Web. 03 Mar 2021.
Vancouver:
Alizadeh E. Topics in cosmology: structure formation, dark energy and recombination. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2011. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/2142/26155.
Council of Science Editors:
Alizadeh E. Topics in cosmology: structure formation, dark energy and recombination. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2011. Available from: http://hdl.handle.net/2142/26155
22.
Gardikiotis, Antonios.
Search for axions via astrophysical obsevations.
Degree: 2015, University of Patras; Πανεπιστήμιο Πατρών
URL: http://hdl.handle.net/10442/hedi/36125
► The present thesis has purpose the axion research (Dark Matter particles) by Astrophysical observations. The main activity has been established in CAST (Cern Axion Solar…
(more)
▼ The present thesis has purpose the axion research (Dark Matter particles) by Astrophysical observations. The main activity has been established in CAST (Cern Axion Solar Telescope) in Geneva. In this thesis the axion detection prospects are defined in parallel with the detector's data analysis. An engineering approach is also given as main and substantial part (fluid dynamics) for the CAST physics reliability. The research is ongoing to the Dark Energy sector willing to explore the possibility of chameleons (dark energy particles) through radiation pressure.
Η παρούσα εργασία έχει ως σκοπό την αναζήτηση αξιονίων (σωματιδίων Σκοτεινής Ύλης) μέσα από αστροφυσικές παρατηρήσεις. Από τις πρώτες παρατηρήσεις της ταχύτητας περιστροφής αστέρων σε σμήνη Γαλαξιών από τον Zwicky και μετά, έγινε σαφές στην επιστημονική κοινότητα πως η ύπαρξη σκοτεινής ύλης καθώς και η κατανόηση της είναι θεμελιώδους σημασίας για την Κοσμολογία. Το ποσοστό της σκοτεινής ύλης του σύμπαντος (~21%), σε σχέση με το αυτό της ύλης που παρατηρούμε (~4%), καθιστά σαφή την αναγκαιότητα για εντατική έρευνα στο πεδίο αυτό της Φυσικής. Ανάγκη δε, προκύπτει επίσης για την εξερεύνηση της σκοτεινής ενέργειας η οποία αποτελεί το υπόλοιπο ~75% του Σύμπαντος. Ένα μικρό μέρος της παρούσας έρευνας στο CERN έχει επικεντρωθεί και στην μελέτη Σκοτεινής ενέργειας καθώς, το πείραμα μέσα από το οποίο προσεγγίζεται η αναζήτηση αξιονίων (CAST – CERN Axion Solar Telescope), προσανατολίζεται συγχρόνως στην έρευνα σωματιδίων Σκοτεινής ενέργειας (χαμαιλέοντες) .
Subjects/Keywords: Αξιόνια; axion; Dark matter; Dark energy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gardikiotis, A. (2015). Search for axions via astrophysical obsevations. (Thesis). University of Patras; Πανεπιστήμιο Πατρών. Retrieved from http://hdl.handle.net/10442/hedi/36125
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Gardikiotis, Antonios. “Search for axions via astrophysical obsevations.” 2015. Thesis, University of Patras; Πανεπιστήμιο Πατρών. Accessed March 03, 2021.
http://hdl.handle.net/10442/hedi/36125.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Gardikiotis, Antonios. “Search for axions via astrophysical obsevations.” 2015. Web. 03 Mar 2021.
Vancouver:
Gardikiotis A. Search for axions via astrophysical obsevations. [Internet] [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 2015. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/10442/hedi/36125.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Gardikiotis A. Search for axions via astrophysical obsevations. [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 2015. Available from: http://hdl.handle.net/10442/hedi/36125
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Utah
23.
Visinelli, Luca.
Axions in cold dark matter and inflation models.
Degree: PhD, Physics & Astronomy, 2011, University of Utah
URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/260/rec/327
► The subjects of this thesis are the invisible axion and the more general family of axion-like particles. The invisible axion is a hypothetical elementary particle…
(more)
▼ The subjects of this thesis are the invisible axion and the more general family of axion-like particles. The invisible axion is a hypothetical elementary particle and a cold dark matter candidate. I present an improved computation of the constraints on the parameter space of the cold dark matter axion in the standard cosmology, that includes the contributions from anharmonicities in the axion potential and from the decay of axionic strings. In this scenario, I update the value of the mass of the cold dark matter axion, fi nding the value (67 ± 17)µeV, approximately one order of magnitude larger than previous computations. The eff ect of nonstandard cosmological scenarios on the parameter space of axion cold dark matter is studied for the first time. In particular, I consider the cases of low-temperature reheating and kination cosmologies, and I show that the mass of the cold dark matter axion can differ from the value in the standard cosmological scenario by orders of magnitude. Finally, I consider the family of axion-like particles, assuming that these particles serve as the inflation in the context; of warm inflation. I find that the axion energy scale f, which in the standard inflation scenario is of the order of the Planck mass, can be lowered to the much safer Grand Uni cation Theory scale f ~ 1016GeV. I also constrain the parameter space and the amount of gravitational waves from this model, using results from the Wilkinson Microwave Anisotropy Probe 7-year data.
Subjects/Keywords: Axions; Cold dark matter; Inflation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Visinelli, L. (2011). Axions in cold dark matter and inflation models. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/260/rec/327
Chicago Manual of Style (16th Edition):
Visinelli, Luca. “Axions in cold dark matter and inflation models.” 2011. Doctoral Dissertation, University of Utah. Accessed March 03, 2021.
http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/260/rec/327.
MLA Handbook (7th Edition):
Visinelli, Luca. “Axions in cold dark matter and inflation models.” 2011. Web. 03 Mar 2021.
Vancouver:
Visinelli L. Axions in cold dark matter and inflation models. [Internet] [Doctoral dissertation]. University of Utah; 2011. [cited 2021 Mar 03].
Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/260/rec/327.
Council of Science Editors:
Visinelli L. Axions in cold dark matter and inflation models. [Doctoral Dissertation]. University of Utah; 2011. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/260/rec/327

University of California – Berkeley
24.
Mardon, Jeremy.
Clues in the Quest for the Invisible Universe.
Degree: Physics, 2011, University of California – Berkeley
URL: http://www.escholarship.org/uc/item/35q8g6xf
► The particle nature of dark matter is one of the most longstanding mysteries of particle physics. In this dissertation I study several potential clues, both…
(more)
▼ The particle nature of dark matter is one of the most longstanding mysteries of particle physics. In this dissertation I study several potential clues, both experimental and theoretical, in the quest to understand this invisible component of the universe. In the last few years, data collected by the PAMELA, ATIC, FERMI and H.E.S.S. experiments has revealed several unexpected features in the fluxes of electron and positron cosmic rays. I investigate an interpretation of these anomalies in terms of dark matter annihilating in our galaxy through a ``cascade'' into electrons or muons. I find good ability to reproduce the data whilst evading other experimental constraints. Inspired by these anomalies, I also investigate a simple framework for dark matter, with many similarities to QCD and well motivated in the context of dynamical solutions to the hierarchy problem. In this framework dark matter decays to standard model particles through a cascade, and I again find that it can provide an excellent fit to cosmic-ray data whilst evading other constraints. I consider the implications at the LHC and in future gamma-ray measurements.More generally, astrophysical and cosmological considerations have a strong interplay with models of physics Beyond the Standard Model and their implications for collider experiments. I investigate the cosmology of the ``Goldstini'' framework in this context. I find that the tensions seen in standard gravitino cosmology are relaxed, and that either gravitinos or goldstinos may be dark matter. I also find that such cosmologically preferred theories may also have the most striking signatures at colliders. The LHC has the potential to observe a ``smoking gun'' signal, in which the Goldstini framework is unambiguously confirmed.
Subjects/Keywords: Physics; BSM; Cosmology; Dark Matter
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Chicago ·
MLA ·
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APA (6th Edition):
Mardon, J. (2011). Clues in the Quest for the Invisible Universe. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/35q8g6xf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mardon, Jeremy. “Clues in the Quest for the Invisible Universe.” 2011. Thesis, University of California – Berkeley. Accessed March 03, 2021.
http://www.escholarship.org/uc/item/35q8g6xf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mardon, Jeremy. “Clues in the Quest for the Invisible Universe.” 2011. Web. 03 Mar 2021.
Vancouver:
Mardon J. Clues in the Quest for the Invisible Universe. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2021 Mar 03].
Available from: http://www.escholarship.org/uc/item/35q8g6xf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mardon J. Clues in the Quest for the Invisible Universe. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/35q8g6xf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Temple University
25.
Love, Christina Elena.
Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber.
Degree: PhD, 2013, Temple University
URL: http://digital.library.temple.edu/u?/p245801coll10,214821
► Physics
Astounding evidence for invisible "dark" matter has been found from galaxy clusters, cosmic and stellar gas motion, gravitational lensing studies, cosmic microwave background analysis,…
(more)
▼ Physics
Astounding evidence for invisible "dark" matter has been found from galaxy clusters, cosmic and stellar gas motion, gravitational lensing studies, cosmic microwave background analysis, and large scale galaxy surveys. Although all studies indicate that there is a dominant presence of non-luminous matter in the universe (about 22 percent of the total energy density with 5 times more dark matter than baryonic matter), its identity and its "direct" detection (through non-gravitational effects) has not yet been achieved. Dark matter in the form of massive, weakly interacting particles (WIMPs) could be detected through their collisions with target nuclei. This requires detectors to be sensitive to very low-energy (less than 100 keV) nuclear recoils with very low expected rates (a few interactions per year per ton of target). Reducing the background in a direct dark matter detector is the biggest challenge. A detector capable of seeing such low-energy nuclear recoils is difficult to build because of the necessary size and the radio- and chemical- purity. Therefore it is imperative to first construct small-scale prototypes to develop the necessary technology and systems, before attempting to deploy large-scale detectors in underground laboratories. Our collaboration, the DarkSide Collaboration, utilizes argon in two-phase time projection chambers (TPCs). We have designed, built, and commissioned DarkSide-10, a 10 kg prototype detector, and are designing and building DarkSide-50, a 50 kg dark matter detector. The present work is an account of my contribution to these efforts. The two-phase argon TPC technology allows powerful discrimination between dark matter nuclear recoils and background events. Presented here are simulations, designs, and analyses involving the electroluminescence in the gas phase from extracted ionization charge for both DarkSide-10 and DarkSide-50. This work involves the design of the HHV systems, including field cages, that are responsible for producing the electric fields that drift, accelerate, and extract ionization electrons. Detecting the ionization electrons is an essential element of the background discrimination and gives event location using position reconstruction. Based on using COMSOL multiphysics software, the TPC electric fields were simulated. For DarkSide-10 the maximum radial displacement a drifting electron would undergo was found to be 0.2 mm and 1 mm for DarkSide-50. Using the electroluminescence signal from an optical Monte Carlo, position reconstruction in these two-phase argon TPCs was studied. Using principal component analysis paired with a multidimensional fit, position reconstruction resolution for DarkSide-10 was found to be less than 0.5 cm and less than 2.5 cm for DarkSide-50 for events occurring near the walls. DarkSide-10 is fully built and has gone through several campaigns of operation and upgrading both at Princeton University and in an underground laboratory (Gran Sasso National Laboratory in Assergi, Italy). Key DarkSide two-phase argon TPC technologies,…
Advisors/Committee Members: Martoff, Charles Jeffrey, Metz, Andreas, Forster, Dieter, Varnum, Susan.
Subjects/Keywords: Astrophysics; Particle physics; dark matter
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Love, C. E. (2013). Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,214821
Chicago Manual of Style (16th Edition):
Love, Christina Elena. “Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber.” 2013. Doctoral Dissertation, Temple University. Accessed March 03, 2021.
http://digital.library.temple.edu/u?/p245801coll10,214821.
MLA Handbook (7th Edition):
Love, Christina Elena. “Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber.” 2013. Web. 03 Mar 2021.
Vancouver:
Love CE. Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber. [Internet] [Doctoral dissertation]. Temple University; 2013. [cited 2021 Mar 03].
Available from: http://digital.library.temple.edu/u?/p245801coll10,214821.
Council of Science Editors:
Love CE. Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber. [Doctoral Dissertation]. Temple University; 2013. Available from: http://digital.library.temple.edu/u?/p245801coll10,214821

University of Saskatchewan
26.
Berezowski, Madeline R.
PeV Scale Dark Skyrmions.
Degree: 2020, University of Saskatchewan
URL: http://hdl.handle.net/10388/12798
► The background information relevant to understanding skyrmions and dark matter is first reviewed. PeV scale skyrmions as a coherent state of dark heavy mesons with…
(more)
▼ The background information relevant to understanding skyrmions and
dark matter is first reviewed. PeV scale skyrmions as a coherent state of
dark heavy mesons with an Anderson-Higgs portal coupling to the Standard Model are analyzed as
dark matter. Their creation would have been non-thermal via a chiral phase transition in the early universe. It turns out that it does not
matter whether the transition is First Order or Second Order. Constraints are put on the skyrmion parameter g
V2MS, where g
V is the Skyrme coupling and M
S is the skyrmion mass, which indicate that it is possible for the skyrmions to be PeV scale and for g
V ≲ 1. For the
dark mesons to not contribute significantly to
dark matter they must be TeV scale if g
wh, their coupling to the Anderson-Higgs field, is to be perturbative. Considering the
dark skyrmions as coherent states of the
dark mesons gives an expression for the skyrmion-nucleon scattering cross section in terms of g
V, g
wh, and M
S. Direct
dark matter detection experiment results are used to constrain g
V in terms of g
wh for 100TeV ≲ M
S ≲ 10PeV. It is possible for g
V to be of perturbative strength, especially for skyrmion masses closer to 10PeV. Future direct detection experiments will yield even more stringent constraints .
Advisors/Committee Members: Dick, Rainer, Green, Robert, Tanaka, Kaori, Ghezelbash, Masoud, Rayan, Steven.
Subjects/Keywords: dark matter; skyrmion; cosmology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Berezowski, M. R. (2020). PeV Scale Dark Skyrmions. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12798
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Berezowski, Madeline R. “PeV Scale Dark Skyrmions.” 2020. Thesis, University of Saskatchewan. Accessed March 03, 2021.
http://hdl.handle.net/10388/12798.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Berezowski, Madeline R. “PeV Scale Dark Skyrmions.” 2020. Web. 03 Mar 2021.
Vancouver:
Berezowski MR. PeV Scale Dark Skyrmions. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/10388/12798.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Berezowski MR. PeV Scale Dark Skyrmions. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/12798
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
Neault, Marie-Pier.
The centres of galaxy group dark matter halos.
Degree: MSc, 2014, McMaster University
URL: http://hdl.handle.net/11375/16314
► Galaxies, galaxy groups and galaxy clusters are embedded in large dark matter halos. Most galaxies in the local universe are found in the galaxy group…
(more)
▼ Galaxies, galaxy groups and galaxy clusters are embedded in large dark matter halos. Most galaxies in the local universe are found in the galaxy group environment. Locating the centres of galaxy groups is crucial in order to study their properties such as their halo masses. It is often assumed that the most massive galaxy (or brightest galaxy) resides at the centre of the gravitational potential. With the aim of evaluating the validity of this paradigm in galaxy groups, we used two different methods to probe the centres of galaxy group halos: the weak gravitational lensing and dynamical methods. We use these two methods to determine the best definition of galaxy group centres.
Our sample is composed of 49 optically (spectroscopically) selected groups and 36 high quality X-ray-selected groups. In total our sample is composed of 78 distinct groups in the redshift range 0.1 < z < 0.9 from the GEEC sample. Our weak lensing analysis suggests that the weighted centre is a better definition than the most massive galaxy position. We address the question of whether or not the result is significantly different for X-ray and optically selected systems. For optically selected systems, the weighted centre is a significantly better assumption of the group centre than the most massive galaxies position. For the X-ray selected groups, the weighted centre and the most massive galaxy appear to trace the centre equally well, although the best definition is the location of the peak in X-ray emission. We evaluate, for the first time, the impact of dynamically complex groups on weak lensing analysis. Once we removed dynamically complex systems from our sample, the lensing signals for all centre definitions are in better agreement suggesting that groups with large offsets between the centre definitions are unevolved systems. For the dynamical method, velocity dispersion profiles suffer from large uncertainties and, therefore, we are unable to place any constraint on the centre definition from this technique.
Thesis
Master of Science (MSc)
Advisors/Committee Members: Parker, Laura, Physics and Astronomy.
Subjects/Keywords: Galaxy Group; Dark Matter Halos
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Neault, M. (2014). The centres of galaxy group dark matter halos. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/16314
Chicago Manual of Style (16th Edition):
Neault, Marie-Pier. “The centres of galaxy group dark matter halos.” 2014. Masters Thesis, McMaster University. Accessed March 03, 2021.
http://hdl.handle.net/11375/16314.
MLA Handbook (7th Edition):
Neault, Marie-Pier. “The centres of galaxy group dark matter halos.” 2014. Web. 03 Mar 2021.
Vancouver:
Neault M. The centres of galaxy group dark matter halos. [Internet] [Masters thesis]. McMaster University; 2014. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/11375/16314.
Council of Science Editors:
Neault M. The centres of galaxy group dark matter halos. [Masters Thesis]. McMaster University; 2014. Available from: http://hdl.handle.net/11375/16314

University of Manchester
28.
Srinivasan, Sankarshana.
CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS.
Degree: 2019, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:319131
► The cold dark matter (CDM) problem is one of the important unsolved problems in cosmology today. The axion is one of the well motivated CDM…
(more)
▼ The cold
dark matter (CDM) problem is one of the
important unsolved problems in cosmology today. The axion is one of
the well motivated CDM candidates whose weak spontaneous decay to
photons is enhanced in the presence of magnetic fields. This thesis
examines the prospects of detecting the axion-photon decay in
astrophysical magnetic fields using radio telescopes, with special
reference to cosmological objects and neutron stars. Cosmological
objects are found to be ill- suited to the detection of the
enhanced decay because of the large scale structure of magnetic
fields in such objects. However, nearby massive galaxy clusters
might offer a chance of detection of the spontaneous decay,
although this requires a clear understanding of the density profile
of such clusters. Neutron stars and their magnetospheres are home
to a resonance effect that could be one of the best chances of
detection in future searches. We develop a general formalism that
allows us to determine the different assumptions that lead to
different results in the literature. We also examine the
detectability of the flux from this resonant decay and find that
radio telescopes are sensitive enough to probe the regions of CDM
axion parameter space hitherto unexplored.
Advisors/Committee Members: PACE, FRANCESCO F, Battye, Richard, Pace, Francesco.
Subjects/Keywords: Dark Matter; Axion; Cosmology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Srinivasan, S. (2019). CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:319131
Chicago Manual of Style (16th Edition):
Srinivasan, Sankarshana. “CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS.” 2019. Doctoral Dissertation, University of Manchester. Accessed March 03, 2021.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:319131.
MLA Handbook (7th Edition):
Srinivasan, Sankarshana. “CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS.” 2019. Web. 03 Mar 2021.
Vancouver:
Srinivasan S. CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS. [Internet] [Doctoral dissertation]. University of Manchester; 2019. [cited 2021 Mar 03].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:319131.
Council of Science Editors:
Srinivasan S. CONVERSION OF COLD DARK MATTER AXIONS TO PHOTONS IN
ASTROPHYSICAL MAGNETIC FIELDS. [Doctoral Dissertation]. University of Manchester; 2019. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:319131
29.
Sonnenfeld, Alessandro.
Luminous and dark matter in early-type galaxies.
Degree: 2015, University of California – eScholarship, University of California
URL: http://www.escholarship.org/uc/item/4gm0j57q
► Three open problems in our understanding of early-type galaxies are 1) identifying theprocess(es) responsible for their rapid size evolution, 2) accurately constraining the stellarIMF and…
(more)
▼ Three open problems in our understanding of early-type galaxies are 1) identifying theprocess(es) responsible for their rapid size evolution, 2) accurately constraining the stellarIMF and its variations in the population, 3) measuring the density profile of their darkmatter halo. We use strong lensing as the main diagnostic tool to address these issues.We first dissected a massive elliptical galaxy in its stellar and dark matter components,measuring both its IMF and the inner slope of the dark matter halo. We then collecteda sample of 45 strong lenses in the redshift interval 0.2 < z < 0.8 and used them, incombination with lenses from other surveys, to measure the slope of the total densityprofile, the stellar IMF and the dark matter mass in the population of massive early-typegalaxies, and their time evolution. Finally, we used our measurements of the evolution ofthe density slope to test a galaxy growth scenario based on purely dissipationless mergers.Our main results are: the stellar IMF of massive early-type galaxies is significantly heavierthan that of the Milky Way and correlates with galaxy mass; the dark matter halo hasa steep slope in at least one system; more compact galaxies have less dark matter thantheir extended counterparts at fixed redshift and stellar mass; early-type galaxies evolvewhile keeping the slope of their total density profile approximately constant. This last result cannot be reproduced with purely dissipationless mergers, therefore a little amountof dissipation is required.
Subjects/Keywords: Astrophysics; Dark matter; Galaxies
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sonnenfeld, A. (2015). Luminous and dark matter in early-type galaxies. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/4gm0j57q
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sonnenfeld, Alessandro. “Luminous and dark matter in early-type galaxies.” 2015. Thesis, University of California – eScholarship, University of California. Accessed March 03, 2021.
http://www.escholarship.org/uc/item/4gm0j57q.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sonnenfeld, Alessandro. “Luminous and dark matter in early-type galaxies.” 2015. Web. 03 Mar 2021.
Vancouver:
Sonnenfeld A. Luminous and dark matter in early-type galaxies. [Internet] [Thesis]. University of California – eScholarship, University of California; 2015. [cited 2021 Mar 03].
Available from: http://www.escholarship.org/uc/item/4gm0j57q.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sonnenfeld A. Luminous and dark matter in early-type galaxies. [Thesis]. University of California – eScholarship, University of California; 2015. Available from: http://www.escholarship.org/uc/item/4gm0j57q
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Victoria
30.
Pearce, James D.
A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV.
Degree: Department of Physics and Astronomy, 2015, University of Victoria
URL: http://hdl.handle.net/1828/6964
► A search for new phenomena in final states with one or more energetic jets and large missing transverse momentum, ETmissT, is presented. An integrated luminosity…
(more)
▼ A search for new phenomena in final states with one or more energetic jets and large missing transverse momentum, ETmissT, is presented. An integrated luminosity of 20 fb-1 is collected from √s = 8 TeV pp collisions at the LHC with the ATLAS detector during 2012 operations. A selection criteria is imposed requiring events to have monojet signatures, with ETmissT > 350 GeV and no identified leptons. Standard Model backgrounds and systematics uncertainties are estimated using a maximum likelihood procedure. The number of events passing this selection criteria is in good agreement with Standard Model expectations. These events are then divided up into three orthogonal signal regions based on the outputs of two Random Forest classifiers trained to classify invisible decays of the Higgs boson produced through the vector boson fusion and Higgs-strahlung production modes. These results are then interpreted in terms of three different Higgs-portal models and translated into upper limits on WIMP-nucleon cross-sections for comparison with direct detection experiments.
Advisors/Committee Members: Kowalewski, Robert V. (supervisor).
Subjects/Keywords: Dark matter; ATLAS; monojet; LHC
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pearce, J. D. (2015). A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV. (Thesis). University of Victoria. Retrieved from http://hdl.handle.net/1828/6964
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pearce, James D. “A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV.” 2015. Thesis, University of Victoria. Accessed March 03, 2021.
http://hdl.handle.net/1828/6964.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pearce, James D. “A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV.” 2015. Web. 03 Mar 2021.
Vancouver:
Pearce JD. A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV. [Internet] [Thesis]. University of Victoria; 2015. [cited 2021 Mar 03].
Available from: http://hdl.handle.net/1828/6964.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pearce JD. A search for Higgs-portal dark matter and new phenomena
with monojet signatures in pp collisions at √s = 8 TeV. [Thesis]. University of Victoria; 2015. Available from: http://hdl.handle.net/1828/6964
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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