Download or read book Searching for Dark Matter with Cosmic Gamma Rays written by Andrea Albert and published by Morgan & Claypool Publishers. This book was released on 2016-09-06 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searching for Dark Matter with Cosmic Gamma Rays summarizes the evidence for dark matter and what we can learn about its particle nature using cosmic gamma rays. It has almost been 100 years since Fritz Zwicky first detected hints that most of the matter in the Universe that doesn't directly emit or reflect light. Since then, the observational evidence for dark matter has continued to grow. Dark matter may be a new kind of particle that is governed by physics beyond our Standard Model of particle physics. In many models, dark matter annihilation or decay produces gamma rays. There are a variety of instruments observing the gamma-ray sky from tens of MeV to hundreds of TeV. Some make deep, focused observations of small regions, while others provide coverage of the entire sky. Each experiment offers complementary sensitivity to dark matter searches in a variety of target sizes, locations, and dark matter mass scales. We review results from recent gamma-ray experiments including anomalies some have attributed to dark matter. We also discuss how our gamma-ray observations complement other dark matter searches and the prospects for future experiments.
Download or read book Searching for Dark Matter with Cosmic Gamma Rays written by A Albert and published by Myprint. This book was released on 2016-09-06 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Very High Energy Cosmic Gamma Radiation written by Felix A. Aharonian and published by World Scientific. This book was released on 2004 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gamma ray astronomy, the branch of high energy astrophysics that studies the sky in energetic ?-ray photons, is destined to play a crucial role in the exploration of nonthermal phenomena in the Universe in their most extreme and violent forms. The great potential of this discipline offers impressive coverage of many OC hot topicsOCO of modern astrophysics and cosmology, such as the origin of galactic and extragalactic cosmic rays, particle acceleration and radiation processes under extreme astrophysical conditions, and the search for dark matter."
Download or read book Optimized Dark Matter Searches in Deep Observations of Segue 1 with MAGIC written by Jelena Aleksić and published by Springer. This book was released on 2015-11-06 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the results of indirect dark matter searches in the gamma-ray sky of the near Universe, as seen by the MAGIC Telescopes. The author has proposed and led the 160 hours long observations of the dwarf spheroidal galaxy Segue 1, which is the deepest survey of any such object by any Cherenkov telescope so far. Furthermore, she developed and completely characterized a new method, dubbed “Full Likelihood”, that optimizes the sensitivity of Cherenkov instruments for detection of gamma-ray signals of dark matter origin. Compared to the standard analysis techniques, this novel approach introduces a sensitivity improvement of a factor of two (i.e. it requires 4 times less observation time to achieve the same result). In addition, it allows a straightforward merger of results from different targets and/or detectors. By selecting the optimal observational target and combining its very deep exposure with the Full Likelihood analysis of the acquired data, the author has improved the existing MAGIC bounds to the dark matter properties by more than one order of magnitude. Furthermore, for particles more massive than a few hundred GeV, those are the strongest constraints from dwarf galaxies achieved by any gamma-ray instrument, both ground-based or space-borne alike.
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 Dark Matter Searches with Gamma Rays from the Galactic Center Halo and Cosmic Ray Antimatter written by James Lee Ryan and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is unknown what constitutes dark matter.The properties of dark matter particles may be observed indirectly if dark matter annihilates or decays into Standard Model particles that are then detected. Work is presented on two such experiments, performed with GAPS and VERITAS. GAPS is a forthcoming balloon-borne cosmic-ray antimatter detector whose unprecedented sensitivity to the fluxes of antiprotons, antideuterons, and antihelium makes possible the detection of a variety of exotic sources of these particles. We outline development of the GAPS TOF system, and demonstrate its ability to achieve desired resolutions in time, position, and energy. VERITAS is an imaging atmospheric Cherenkov telescope array that has been observing gamma rays from the Galactic Center region for over 10 years. We develop a template-based background estimation method to look for excess gamma rays in the Galactic Center halo. No significant excess is found, and limits on the thermally-averaged annihilation cross section are derived with dependence on the annihilation channel, reaching $\langle \sigma_\text{ann} v\rangle
Download or read book Searching for Dark Matter with Cosmic Gamma Rays written by Andrea Albert and published by Morgan & Claypool Publishers. This book was released on 2016-09-06 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searching for Dark Matter with Cosmic Gamma Rays summarizes the evidence for dark matter and what we can learn about its particle nature using cosmic gamma rays. It has almost been 100 years since Fritz Zwicky first detected hints that most of the matter in the Universe that doesn't directly emit or reflect light. Since then, the observational evidence for dark matter has continued to grow. Dark matter may be a new kind of particle that is governed by physics beyond our Standard Model of particle physics. In many models, dark matter annihilation or decay produces gamma rays. There are a variety of instruments observing the gamma-ray sky from tens of MeV to hundreds of TeV. Some make deep, focused observations of small regions, while others provide coverage of the entire sky. Each experiment offers complementary sensitivity to dark matter searches in a variety of target sizes, locations, and dark matter mass scales. We review results from recent gamma-ray experiments including anomalies some have attributed to dark matter. We also discuss how our gamma-ray observations complement other dark matter searches and the prospects for future experiments.
Download or read book The Mystery of Dark Matter written by Wolfgang Kapferer and published by Springer Nature. This book was released on 2021-04-17 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: Get ready to embark on the exciting search for dark matter—the invisible mass that dominates our universe. This popular science book explains why this mysterious dark matter has been incorporated into the standard model of the universe and how scientists are able to “observe” the invisible. The book starts with the early indications of the existence of dark matter, including the strange cohesion of galaxy clusters, before moving on to modern observations like cosmic background radiation. Along the way, you will learn about the direct and indirect methods being used by researchers to track down dark matter and whatever is behind this strange phenomenon. The Mystery of Dark Matter will appeal to general readers who wish to understand what scientists actually know about dark matter, along with the methods they use to help crack the mystery. This book is a translation of the original German 1st edition Das Rätsel Dunkle Materie by Wolfgang Kapferer, published by Springer-Verlag GmbH Deutschland in 2018.The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com). A subsequent human revision was done primarily in terms of content, so that the book will read stylistically differently from a conventional translation. Springer Nature works continuously to further the development of tools for the production of books and on the related technologies to support the authors.
Download or read book Cosmic Rays and Dark Matter written by Yasushi Muraki and published by . This book was released on 2004 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Searching for Dark Matter with Imaging Atmospheric Cherenkov Telescopes written by Alessandro Montanari and published by Springer. This book was released on 2024-10-21 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive review of the methodologies and searches for dark matter (DM) annihilation signals using very-high-energy gamma rays (VHE, E > 100 GeV), utilizing data from current Imaging Atmospheric Cherenkov Telescopes (IACTs) in the pre-Cherenkov Telescope Array (CTA) era. It presents the state-of-the-art statistical analysis methods and theoretical models related to TeV DM, applied to data from the H.E.S.S. telescope array, which is currently the most sensitive IACT array for observing the Galactic Center (GC), where the brightest DM annihilation signals are expected. The authors delve into the astrophysics of VHE gamma-ray production through cosmic ray acceleration. They explain the Imaging Atmospheric Cherenkov technique, describe the H.E.S.S. array, and discuss possibilities for DM annihilation-induced gamma-ray spectra and DM distribution profiles. By employing advanced statistical methods, they search for weak signals in the GC region using the H.E.S.S. Inner Galaxy Survey dataset and address systematic uncertainties. The authors present and debate the most constraining results on TeV dark matter models. Finally, this book presents the sensitivity of current IACTs to DM annihilation signals using IGS mock datasets, accounting for systematic and instrumental uncertainties. Detection prospects for canonical TeV DM models, such as the Wino, Higgsino, and quintuplet, are discussed. Sensitivity benchmarks on indirect DM searches with IACTs using H.E.S.S. as an example are provided, setting the stage for future developments in the CTA era. It serves as a consolidated resource for graduate students and researchers, presenting methodologies that could lead to significant advancements in the quest to understand dark matter.
Download or read book Constraining TeV scale Astrophysical Foregrounds for Dark Matter Searches with HAWC written by Mehr Un Nisa and published by . This book was released on 2019 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Astrophysical observations are central to the quest for new physics including the search for dark matter. The search is based on identifying potential deviations from the Standard Model in the cosmic-ray and the electromagnetic spectrum of astrophysical sources. The deviations could either be signatures of dark matter or have consequences for our understanding of known sources. The last decade of precision measurements from detectors in space, such as the Fermi Gamma-ray Space Telescope, and the Alpha Magnetic Spectrometer for detecting cosmic rays aboard the International Space Station, have identified certain "anomalies" or unexpected spectral features, that challenge the standard models of how cosmic rays are produced and propagate through the Galaxy. Examples include an unexpectedly hard spectrum of cosmic-ray antiprotons at energies above a few hundred GeV, and an unexplained excess of very-high-energy gamma rays from the Sun. An excess of cosmic-ray antiprotons and a hard spectrum of gamma rays from the Sun also feature in the predictions of various models of dark matter annihilation. However, without a complete understanding of the antiproton spectrum, and the production mechanisms of solar gamma rays, it is impossible to differentiate new physics from the standard astrophysical foreground flux of these particles. Measuring these fluxes at energies that extend into the TeV range is an observational challenge that we explore in this thesis. The High AltitudeWater Cherenkov (HAWC) Observatory is a wide field-of-view array that is currently the only detector capable of making high-statistics measurements of cosmic rays and gamma rays at multi-TeV energies. This work uses data from HAWC collected between 2014-2017 to constrain two unique fluxes at the TeV scale: antiprotons in Galactic cosmic rays, and gamma rays from the quiescent Sun - both relevant foregrounds for astrophysical searches for physics beyond the Standard Model. Cosmic rays in the inner solar system are subject to deflection by the magnetic fields of the Earth and the Sun, affecting the observed deficit or "shadow" of the Moon/Sun. Cosmic rays also interact with the Sun's atmosphere to produce a steady emission of gamma rays up to at least 200 GeV, though the exact underlying mechanism remains a puzzle. We present the strongest upper limits on the antiproton to proton ratio in TeV cosmic rays at ~1% using the Moon shadow as a momentum/ charge discriminant. We also discuss our search for excess gamma rays from the Sun above 1 TeV, and present the resulting implications for models of dark matter capture and annihilation in the Sun. Our results constrain the steady gamma-ray emission from the Sun up to a few times 10−12 TeV cm−2 s−1 at 1 TeV. For dark matter annihilation with long-lived mediators in the Sun, we present the strongest upper limits on dark matter-proton scattering cross section up to ~10−45 cm2, which is a potential improvement of four orders of magnitude compared to direct-detection experiments for dark matter mass of 1 TeV."--Pages xi-xii.
Download or read book Particle Dark Matter written by Gianfranco Bertone and published by Cambridge University Press. This book was released on 2010-01-07 with total page 763 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the dark matter problem in particle physics, astrophysics and cosmology for graduate students and researchers.
Download or read book The Search for WIMP Dark Matter Continuum Gamma ray Emission from Dark Matter Satellites in the Milky Way Using the Fermi LAT written by Wang Ping and published by Stanford University. This book was released on 2011 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Identification Of Dark Matter The Proceedings Of The Sixth International Workshop written by Minos Axenides and published by World Scientific. This book was released on 2007-08-31 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is the latest in a prominent biannual series of scientific meetings on the exciting research topics of dark matter and, more recently, of dark energy. It contains a state-of-the-art update on detection efforts by experimental groups around the world trying to pin down exotic new forms of matter under the names of axions, neutralinos, wimps, primordial black holes, q balls, sterile neutrinos, as well as a tantalizing new form of dark energy component called phantom energy and quintessence. The book is self-contained as it also includes general reviews on recent cosmological observations — supernovae measurements, cosmic matter distribution surveys and cosmic radiation anisotropies — introducing even the uninitiated reader to this fascinating frontier of research.
Download or read book Indirect Dark Matter Searches in the Gamma ray Band and Development of New Analysis Techniques for Ground based Gamma ray Astronomy written by Tjark Miener and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arrays of imaging atmospheric Cherenkov telescopes (IACTs) probe the very highenergy (VHE) gamma-ray sky. Their working principle consists of the simultaneous observation of air showers initiated by the interaction of VHE gamma rays and cosmic rays with the atmosphere. Cherenkov photons induced by a given shower are focused onto the camera plane of the telescopes in the array, producing a stereoscopic record of the event. This image contains the longitudinal development of the airshower, together with its spatial, temporal, and calorimetric information. The properties of the originating VHE particle (type, energy, and incoming direction) can be inferred from those images by reconstructing the whole event using machine learning techniques. In this thesis, a purely deep learning (DL) driven full-event reconstruction of simulated, stereoscopic IACT events of the future Cherenkov Telescope Array (CTA) is presented. In addition, we apply DL algorithms on real observational IACT data, utilizing Crab Nebula observations by the MAGIC telescopes. In order to conduct all necessary research to achieve the former milestones we developed CTLearn, a package that includes modules for loading and manipulating IACT data and for running DL models, using pixel-wise camera data as input...
Download or read book In Search of Dark Matter written by Ken Freeman and published by Springer Science & Business Media. This book was released on 2006-08-25 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written for the educated non-scientist and scientist alike, it spans a variety of scientific disciplines, from observational astronomy to particle physics. Concepts that the reader will encounter along the way are at the cutting edge of scientific research. However the themes are explained in such a way that no prior understanding of science beyond a high school education is necessary.
Download or read book Dark Matter in Astrophysics and Particle Physics written by Hans Volker Klapdor-Kleingrothaus and published by World Scientific. This book was released on 2010 with total page 603 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark matter and dark energy are one of the central mysteries in modern physics, although modern astrophysical and cosmological observations and particle physics experiments can and will provide vital clues in uncovering its true nature. The DARK 2009 Conference brought together World?s leading researchers in both astrophysics and particle physics, providing an opportunity and platform to present their latest results to the community. The topics covered are wide-ranging, from terrestrial underground experiments to space experimental efforts to search for dark matter, and on the theoretical aspects, from the generating of a fifth family as origin of dark matter, extra dimensions and dark matter to non-standard Wigner classes and dark matter. One of the new highlights was certainly a possible connection between a neutrino mass as observed by nuclear double beta decay and the dark energy. Highly important and relevant in its field, the book presents a vital snapshot of the sometimes seemingly disparate areas of dark matter research and offers an exciting overview of current ideas and future directions.
