The Search For Wimp Dark Matter Continuum Gamma Ray Emission From Dark Matter Satellites In The Milky Way Using The Fermi Lat PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download The Search For Wimp Dark Matter Continuum Gamma Ray Emission From Dark Matter Satellites In The Milky Way Using The Fermi Lat PDF full book. Access full book title The Search For Wimp Dark Matter Continuum Gamma Ray Emission From Dark Matter Satellites In The Milky Way Using The Fermi Lat.
Author | : Wang Ping |
Publisher | : Stanford University |
Total Pages | : 167 |
Release | : 2011 |
Genre | : |
ISBN | : |
Download The Search for WIMP Dark Matter Continuum Gamma-ray Emission from Dark Matter Satellites in the Milky Way Using the Fermi LAT Book in PDF, ePub and Kindle
This thesis focuses on the search for unknown dark matter (DM) satellites in the Milky Way using the Fermi Large Area Space Telescope (LAT). The Fermi Gamma-ray Space Telescope (Fermi) is a next generation space observatory, which was successfully launched on June 11th, 2008. The LAT is the principal scientific instrument onboard. Its unprecedented angular resolution and sensitivity in the 100 MeV to > 300 GeV energy range makes it an excellent instrument for probing the sky for DM satellites. Current N-body simulations based on the Lambda-CDM cosmology model predict a large number of as yet unobserved DM satellites in our galaxy; some satellites are predicted to be extended sources (> 1deg extension) as seen by the LAT. Our work assumes that a significant component of DM is a Weakly Interacting Massive Particle (WIMP) in the 100 GeV mass range. The annihilation of WIMPs results in many high energy gamma rays that can be well measured by the LAT. The WIMP produced gamma-ray spectrum from the putative DM satellites is considerably harder than most astrophysical sources. Also, DM satellites have no astronomical counterparts in the X-ray and radio bands, and the emission has no time variability. My thesis will focus on a blind analysis in the search for unknown DM satellites using one year of LAT data, and setting constraints on some WIMP models based on the results of our analysis in which we find no candidates.
Author | : Wang Ping |
Publisher | : |
Total Pages | : |
Release | : 2011 |
Genre | : |
ISBN | : |
Download The Search for WIMP Dark Matter Continuum Gamma-ray Emission from Dark Matter Satellites in the Milky Way Using the Fermi LAT Book in PDF, ePub and Kindle
This thesis focuses on the search for unknown dark matter (DM) satellites in the Milky Way using the Fermi Large Area Space Telescope (LAT). The Fermi Gamma-ray Space Telescope (Fermi) is a next generation space observatory, which was successfully launched on June 11th, 2008. The LAT is the principal scientific instrument onboard. Its unprecedented angular resolution and sensitivity in the 100 MeV to> 300 GeV energy range makes it an excellent instrument for probing the sky for DM satellites. Current N-body simulations based on the Lambda-CDM cosmology model predict a large number of as yet unobserved DM satellites in our galaxy; some satellites are predicted to be extended sources (> 1deg extension) as seen by the LAT. Our work assumes that a significant component of DM is a Weakly Interacting Massive Particle (WIMP) in the 100 GeV mass range. The annihilation of WIMPs results in many high energy gamma rays that can be well measured by the LAT. The WIMP produced gamma-ray spectrum from the putative DM satellites is considerably harder than most astrophysical sources. Also, DM satellites have no astronomical counterparts in the X-ray and radio bands, and the emission has no time variability. My thesis will focus on a blind analysis in the search for unknown DM satellites using one year of LAT data, and setting constraints on some WIMP models based on the results of our analysis in which we find no candidates.
Author | : Miguel A. Sánchez-Conde |
Publisher | : MDPI |
Total Pages | : 220 |
Release | : 2020-05-28 |
Genre | : Mathematics |
ISBN | : 3039360442 |
Download The Role of Halo Substructure in Gamma-Ray Dark Matter Searches Book in PDF, ePub and Kindle
An important, open research topic today is to understand the relevance that dark matter halo substructure may have for dark matter searches. In the standard cosmological model, halo substructure or subhalos are predicted to be largely abundant inside larger halos, for example, galaxies such as ours, and are thought to form first and later merge to form larger structures. Dwarf satellite galaxies—the most massive exponents of halo substructure in our own galaxy—are already known to be excellent targets for dark matter searches, and indeed, they are constantly scrutinized by current gamma-ray experiments in the search for dark matter signals. Lighter subhalos not massive enough to have a visible counterpart of stars and gas may be good targets as well, given their typical abundances and distances. In addition, the clumpy distribution of subhalos residing in larger halos may boost the dark matter signals considerably. In an era in which gamma-ray experiments possess, for the first time, the exciting potential to put to test the preferred dark matter particle theories, a profound knowledge of dark matter astrophysical targets and scenarios is mandatory should we aim for accurate predictions of dark matter-induced fluxes for investing significant telescope observing time on selected targets and for deriving robust conclusions from our dark matter search efforts. In this regard, a precise characterization of the statistical and structural properties of subhalos becomes critical. In this Special Issue, we aim to summarize where we stand today on our knowledge of the different aspects of the dark matter halo substructure; to identify what are the remaining big questions, and how we could address these; and, by doing so, to find new avenues for research.
Author | : Alberto Salvio |
Publisher | : Frontiers Media SA |
Total Pages | : 265 |
Release | : 2019-12-06 |
Genre | : |
ISBN | : 2889632059 |
Download From the Fermi Scale to Cosmology Book in PDF, ePub and Kindle
Author | : |
Publisher | : |
Total Pages | : 8 |
Release | : 2015 |
Genre | : |
ISBN | : |
Download Dark Matter Searches with the Fermi-LAT in the Direction of Dwarf Spheroidals Book in PDF, ePub and Kindle
Author | : Andrea Marie Albert |
Publisher | : |
Total Pages | : |
Release | : 2013 |
Genre | : |
ISBN | : |
Download Search for Gamma-ray Spectral Lines with the Fermi Large Area Telescope and Dark Matter Implications Book in PDF, ePub and Kindle
Abstract: Measurements indicate that ~85% of the matter in the universe neither emits nor reflects light--appropriately called "dark matter". We believe dark matter may be primary composed of new particles, but we know very little about their nature. What dark matter is and how it interacts is one of the top cosmological mysteries today. Detecting a signal from particle dark matter would not only offer insight into the fundamental nature of dark matter, but it would also be strong evidence for physics existing beyond the Standard Model. A promising dark matter candidate is a weakly interacting massive particle (WIMP). Measurements indicate that the Milky Way Galaxy resides in a halo of dark matter, making it an ideal laboratory for investigating these elusive particles. As WIMPs are predicted to be heavy, their interactions should produce high-energy gamma rays that would be detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope (Fermi). If WIMPs annihilate directly into gamma rays, the gamma-ray energy would be the same as the rest mass energy of the WIMPs, which is currently unknown. This process would cause a "pile-up" of gamma rays at a specific energy, producing a sharp line (or bump) in the otherwise relatively smooth gamma-ray energy spectrum. This distinctive signal would not only be strong evidence for the existence of WIMPs, but would also provide information about their mass. We have searched for spectral lines in the energy range 5 to 300 GeV using 3.7 years of Fermi LAT data, reprocessed with updated calorimeter calibration constants, and an improved energy dispersion model from previous LAT Collaboration line searches. We search in five regions selected to optimize sensitivity to different theoretically-motivated density distributions of WIMPs. We do not find any globally significant lines in our a priori search regions and present 95% confidence limits for annihilation cross section and decay lifetimes. We extensively discuss potential systematic effects in the search. Finally, we consider claims of evidence for a spectral line at 130 GeV, compare our results to previous work, and discuss why this search finds a somewhat lower statistical significance for a potential line than other works.
Author | : |
Publisher | : |
Total Pages | : 25 |
Release | : 2010 |
Genre | : |
ISBN | : |
Download Observations of MilkyWay Dwarf Spheroidal Galaxies with the Fermi-LAT Detector and Book in PDF, ePub and Kindle
We report on the observations of 14 dwarf spheroidal galaxies with the Fermi Gamma-Ray Space Telescope taken during the first 11 months of survey mode operations. The Fermi telescope, which is conducting an all-sky [gamma]-ray survey in the 20 MeV to>300 GeV energy range, provides a new opportunity to test particle dark matter models through the expected [gamma]-ray emission produced by pair annihilation of weakly interacting massive particles (WIMPs). Local Group dwarf spheroidal galaxies, the largest galactic substructures predicted by the cold dark matter scenario, are attractive targets for such indirect searches for dark matter because they are nearby and among the most extreme dark matter dominated environments. No significant [gamma]-ray emission was detected above 100 MeV from the candidate dwarf galaxies. We determine upper limits to the [gamma]-ray flux assuming both power-law spectra and representative spectra from WIMP annihilation. The resulting integral flux above 100 MeV is constrained to be at a level below around 10−9 photons cm−2s−1. Using recent stellar kinematic data, the [gamma]-ray flux limits are combined with improved determinations of the dark matter density profile in 8 of the 14 candidate dwarfs to place limits on the pair annihilation cross-section ofWIMPs in several widely studied extensions of the standard model, including its supersymmetric extension and other models that received recent attention. With the present data, we are able to rule out large parts of the parameter space where the thermal relic density is below the observed cosmological dark matter density and WIMPs (neutralinos here) are dominantly produced non-thermally, e.g. in models where supersymmetry breaking occurs via anomaly mediation. The [gamma]-ray limits presented here also constrain some WIMP models proposed to explain the Fermi and PAMELA ee− data, including low-mass wino-like neutralinos and models with TeV masses pair-annihilating into muon-antimuon pairs.
Author | : Subhendra Mohanty |
Publisher | : Springer Nature |
Total Pages | : 296 |
Release | : 2020-10-09 |
Genre | : Science |
ISBN | : 3030562018 |
Download Astroparticle Physics and Cosmology Book in PDF, ePub and Kindle
Cosmology and astroparticle physics have seen an avalanche of discoveries in the past decade (IceCube - high energy neutrinos, LIGO - gravitational waves, Fermi- gamma-ray telescope, Xenon-1T - dark matter detection, PLANCK- cosmic microwave radiation, EHT picture of black hole, SDSS -galaxy surveys), all of which require a multidisciplinary background for analyzing the phenomena. The arena for testing particle physics models is in the multimessenger astronomical observations and at the same time cosmology now requires a particle physics basis for explaining many phenomena. This book discusses the theoretical tools of particle physics and general relativity which are essential for understanding and correlating diverse astronomical observations.
Author | : |
Publisher | : |
Total Pages | : 2 |
Release | : 2007 |
Genre | : |
ISBN | : |
Download Analysis Methods for Milky Way Dark Matter Satellite Detection Book in PDF, ePub and Kindle
The Gamma Ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) Dark Matter and New Physics Working group has been developing approaches for the indirect detection of in situ annihilation of dark matter. Our work has assumed that a significant component of dark matter is a new type of Weakly Interacting Massive Particle (WIMP) in the 100GeV mass range. The annihilation of two WIMPs results in the production of a large number of high energy gamma rays (>1GeV) that can be well measured by the GLAST LAT. The cold dark matter model implies a significant number of as yet unobserved dark matter satellites in our galaxy. The spectra of these galactic satellites are considerably harder than most, if not all, astrophysical sources, have an endpoint at the mass of the WIMP, and are not power laws. We describe a preliminary feasibility study for the indirect detection of dark matter satellites in the Milky Way using the GLAST LAT.
Author | : Gianfranco Bertone |
Publisher | : Cambridge University Press |
Total Pages | : 763 |
Release | : 2010-01-07 |
Genre | : Science |
ISBN | : 0521763681 |
Download Particle Dark Matter Book in PDF, ePub and Kindle
Describes the dark matter problem in particle physics, astrophysics and cosmology for graduate students and researchers.