Download or read book Search for a Dark Matter Gamma ray Signal from Dwarf Spheroidal Galaxies with CACTUS written by Peter Anthony Marleau and published by . This book was released on 2007 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dark Matter and Gamma rays from Draco written by and published by . This book was released on 2005 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dwarf spheroidal galaxy Draco has long been considered likely to be one of the brightest point sources of gamma-rays generated through dark matter annihilations. Recent studies of this object have found that it remains largely intact from tidal striping, and may be more massive than previously thought. In this article, we revisit Draco as a source of dark matter annihilation radiation, with these new observational constraints in mind. We discuss the prospects for the experiments MAGIC and GLAST to detect dark matter in Draco, as well as constraints from the observations of EGRET. We also discuss the possibility that the CACTUS experiment has already detected gamma-rays from Draco. We find that it is difficult to generate the flux reported by CACTUS without resorting to non-thermally produced WIMPs and/or a density spike in Draco's dark matter distribution due to the presence of an intermediate mass black hole. We also find that for most annihilation modes, a positive detection of Draco by CACTUS would be inconsistent with the lack of events seen by EGRET.
Download or read book Improving the Sensitivity of Gamma ray Telescopes to Dark Matter Annihilation in Dwarf Spheroidal Galaxies written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermi-LAT Collaboration has studied the gamma-ray emission from a stacked population of dwarf spheroidal galaxies and used this information to set constraints on the dark matter annihilation cross section. Interestingly, their analysis uncovered an excess with a test statistic (TS) of 8.7. If interpreted naively, this constitutes a 2.95[sigma] local excess (p-value=0.003), relative to the expectations of their background model. In order to further test this interpretation, the Fermi-LAT team studied a large number of blank sky locations and found TS>8.7 excesses to be more common than predicted by their background model, decreasing the significance of their dwarf excess to 2.2[sigma](p-value=0.027). We argue that these TS>8.7 blank sky locations are largely the result of unresolved blazars, radio galaxies, and star-forming galaxies, and show that multiwavelength information can be used to reduce the degree to which such sources contaminate the otherwise blank sky. In particular, we show that masking regions of the sky that lie within 1° of sources contained in the BZCAT or CRATES catalogs reduce the fraction of blank sky locations with TS>8.7 by more than a factor of 2. Taking such multiwavelength information into account can enable experiments such as Fermi to better characterize their backgrounds and increase their sensitivity to dark matter in dwarf galaxies, the most important of which remain largely uncontaminated by unresolved point sources. We also note that for the range of dark matter masses and annihilation cross sections currently being tested by studies of dwarf spheroidal galaxies, simulations predict that Fermi should be able to detect a significant number of dark matter subhalos. These subhalos constitute a population of subthreshold gamma-ray point sources and represent an irreducible background for searches for dark matter annihilation in dwarf galaxies.
Download or read book The Role of Halo Substructure in Gamma Ray Dark Matter Searches written by Miguel A. Sánchez-Conde and published by MDPI. This book was released on 2020-05-28 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Searches for Dark Matter Self annihilation Signals from Dwarf Spheroidal Galaxies and the Fornax Galaxy Cluster with Imaging Air Cherenkov Telescopes written by Björn Helmut Bastian Opitz and published by . This book was released on 2014 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dark Matter Profiles and Annihilation in Dwarf Spheroidal Galaxies written by and published by . This book was released on 2013 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Searches for Gamma ray Lines and pure WIMP Spectra from Dark Matter Annihilations in Dwarf Galaxies with H E S S written by H. Abdalla and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detection of Gamma ray Sources and Search for Dark Matter Signals with Cherenkov Telescope Array Surveys written by Veronika Vodeb and published by . This book was released on 2024 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particles and Nuclei written by Peter D. Barnes and published by AIP Conference Proceedings / H. This book was released on 2006-10-04 with total page 1216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the proceedings of the 17th International Conference on Particles and Nuclei, Santa Fe, New Mexico, USA which was concerned with new developments in experimental and theoretical particle physics, nuclear physics, and cosmology, and the intersections of these fields which will help us understand our Universe more completely. The participants reported on new developments in instrumentation, including large-scale facilities, such as accelerators, that will be essential for future work.
Download or read book On the Relevance of Sharp Gamma ray Features for Indirect Dark Matter Searches written by and published by . This book was released on 2011 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dark Matter Annihilation in The Galactic Center As Seen by the Fermi Gamma Ray Space Telescope written by and published by . This book was released on 2010 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Dark Side of the Universe written by Carlos Muñoz and published by . This book was released on 2006 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this workshop was to bring the experts in the field of Astroparticle Physics and related topics (particle physics, astrophysics, and cosmology) to discuss on the latest theroetical and experimental advances. The topics of the workshop included: direct and indirect detection of dark matter, particle candidates for dark matter, supersymmetry, astrophysical analyses of galactic halos, dark energy, inflation, leptogenesis, neutrinos, axion-like particles, ultra high energy cosmic rays, gamma ray bursts, string landscape and anthropic reasoning.
Download or read book Rotating Relativistic Stars written by John L. Friedman and published by Cambridge University Press. This book was released on 2013-02-11 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: The masses of neutron stars are limited by an instability to gravitational collapse and an instability driven by gravitational waves limits their spin. Their oscillations are relevant to x-ray observations of accreting binaries and to gravitational wave observations of neutron stars formed during the coalescence of double neutron-star systems. This volume includes more than forty years of research to provide graduate students and researchers in astrophysics, gravitational physics and astronomy with the first self-contained treatment of the structure, stability and oscillations of rotating neutron stars. This monograph treats the equations of stellar equilibrium; key approximations, including slow rotation and perturbations of spherical and rotating stars; stability theory and its applications, from convective stability to the r-mode instability; and numerical methods for computing equilibrium configurations and the nonlinear evolution of their oscillations. The presentation of fundamental equations, results and applications is accessible to readers who do not need the detailed derivations.
Download or read book Merriam Webster s Vocabulary Builder written by Mary W. Cornog and published by Merriam-Webster. This book was released on 1998 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ideal book for people who want to increase their word power. Thorough coverage of 1,200 words and 240 roots while introducing 2,300 words. The Vocabulary Builder is organized by Greek and Latin roots for effective study with nearly 250 new words and roots. Includes quizzes after each root discussion to test progress. A great study aid for students preparing to take standardized tests.
Download or read book Highlights of Spanish Astrophysics II written by Sociedad Española de Astronomía. Scientific Meeting and published by Springer Science & Business Media. This book was released on 2001-07-31 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume documents the contributions presented at the 4th Scientific Meeting of the Spanish Astronomical Society (SEA). Covering a wide range of topics, the 146 contributed papers give a comprehensive overview of the current state of Spanish astronomy. The Proceedings include special reviews dealing with the cosmological information obtained from galaxy spectra, supernovae at high redshift, black holes, dynamics of galaxy interactions, and non-LTE inversion of spectral lines. The contents of these Proceedings thus reflect the broad interests of the Spanish astronomical community. The symbolic significance of these proceedings can hardly be exaggerated, since here, for the second time, the SEA publishes the proceedings of its own scientific meeting. This book is recommended to professional astronomers and astronomy graduate students worldwide.
Download or read book An Introduction to Particle Dark Matter written by Stefano Profumo and published by Wspc (Europe). This book was released on 2017 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle dark matter: the name of the game -- The thermal relic paradigm: zeroth-order lessons from cosmology -- The thermal relic paradigm: a closer look -- The art of WIMP direct detection -- Indirect dark matter searches -- Searching for dark matter with particle colliders -- Axions and axion-like particles as dark matter -- Sterile neutrinos as dark matter particles -- Bestiarium: a short, biased compendium of notable dark matter particle candidates and models
Download or read book Very High Energy Gamma Ray Astronomy written by T.C. Weekes and published by CRC Press. This book was released on 2003-04-08 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: High energy gamma-ray photons are the prime probes of the relativistic or high-energy universe, populated by black holes, neutron stars, supernovae, quasars, and matter-antimatter annihilations. Through studying the gamma-ray sky, astrophysicists are able to better understand the formation and behavior of these exotic and energetic bodies. V
