English
Related papers

Related papers: Luminosity functions consistent with a pulsar-domi…

200 papers

We present methods to assess whether gamma-ray excesses towards Milky Way dwarf galaxies can be attributed to astrophysical sources rather than to dark matter annihilation. As a case study we focus on Reticulum II, the dwarf which shows the…

High Energy Astrophysical Phenomena · Physics 2018-07-24 Alex Geringer-Sameth , Savvas M. Koushiappas , Matthew G. Walker , Vincent Bonnivard , Céline Combet , David Maurin

Three regions of excessive flux of cosmic rays with energies of the order of PeV are found in the experimental data of the EAS MSU array at a confidence level greater than 4\sigma. For two of them, there are similar regions in the…

High Energy Astrophysical Phenomena · Physics 2011-12-24 G. V. Kulikov , M. Yu. Zotov

Context. More than one hundred GeV pulsars have been detected up to now by the LAT telescope on the Fermi gamma-ray observatory, showing peak energies around a few GeV. Current modelling proposes that the high energy emission comes from…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Ioanna Arka , Guillaume Dubus

We have used millisecond pulsars (MSPs) from the southern High Time Resolution Universe (HTRU) intermediate latitude survey area to simulate the distribution and total population of MSPs in the Galaxy. Our model makes use of the scale…

We apply a likelihood analysis to pulsar detections, pulsar upper limits, and diffuse background measurements from the OSSE and EGRET instruments on the Compton Gamma Ray Observatory to constrain the luminosity law for gamma-ray pulsars and…

Astrophysics · Physics 2009-10-31 M. A. McLaughlin , J. M. Cordes

The Fermi gamma ray space telescope data have pointed towards an excess of gamma rays with a peak around $1-3$ GeV in the region surrounding the galactic center. This anomalous excess can be described well by a dark matter candidate having…

High Energy Physics - Phenomenology · Physics 2018-05-09 Debasish Borah , Arnab Dasgupta

The Milky Way's Galactic Center harbors a gamma-ray excess that is a candidate signal of annihilating dark matter. Dwarf galaxies remain predominantly dark in their expected commensurate emission. In this work we quantify the degree of…

High Energy Astrophysical Phenomena · Physics 2018-05-16 Ryan E. Keeley , Kevork N. Abazajian , Anna Kwa , Nicholas L. Rodd , Benjamin R. Safdi

Fermi-LAT observations of the Galactic Center (GC) have revealed a spherically- symmetric excess of GeV gamma rays extending to at least 10 deg from the dynamical center of the Galaxy. A critical uncertainty in extracting the intensity,…

High Energy Astrophysical Phenomena · Physics 2016-09-14 Eric Carlson , Tim Linden , Stefano Profumo

Detection of point sources in images is a fundamental operation in astrophysics, and is crucial for constraining population models of the underlying point sources or characterizing the background emission. Standard techniques fall short in…

Instrumentation and Methods for Astrophysics · Physics 2018-02-28 Tansu Daylan , Stephen K. N. Portillo , Douglas P. Finkbeiner

The reported excess of $\gamma$-rays, emitted from an extended region around the galactic center, has a distribution and rate suggestive of an origin in dark matter (DM) annihilations. The conventional annihilation channels into standard…

High Energy Physics - Phenomenology · Physics 2015-06-23 Marat Freytsis , Dean J. Robinson , Yuhsin Tsai

We present the first results from the \xmm Galactic Plane Survey (XGPS). In the first phase of the programme, 22 pointings were used to cover a region of approximately three square degrees between 19\deg -- 22\deg in Galactic longitude and…

Astrophysics · Physics 2009-11-10 A. D. P. Hands , R. S. Warwick , M. G. Watson , D. J. Helfand

Several groups have analyzed the publicly-available Fermi-LAT data and reported a spatially extended $\gamma-$ray excess of around $1-3$ GeV from the region surrounding the Galactic Center that might originate from annihilation of dark…

High Energy Astrophysical Phenomena · Physics 2015-06-24 Bei Zhou , Yun-Feng Liang , Xiaoyuan Huang , Xiang Li , Yi-Zhong Fan , Lei Feng , Jin Chang

Observations by the Fermi-LAT telescope have uncovered a significant $\gamma$-ray excess toward the Milky Way Galactic Center. There has been no detection of a similar signal in the direction of the Milky Way dwarf spheroidal galaxies.…

High Energy Physics - Phenomenology · Physics 2015-06-03 Manoj Kaplinghat , Tim Linden , Hai-Bo Yu

The Milky Way centre exhibits an intense flux in the gamma and X-ray bands, whose origin is partly ascribed to the possible presence of a large population of millisecond pulsars (MSPs) and cataclysmic variables (CVs), respectively. However,…

Astrophysics of Galaxies · Physics 2018-06-13 Manuel Arca-Sedda , Bence Kocsis , Timothy Brandt

Astrophysical sources outside the Milky Way, such as active galactic nuclei and star-forming galaxies, leave their imprint on the gamma-ray sky as nearly isotropic emission referred to as the Extragalactic Gamma-Ray Background (EGB). While…

High Energy Astrophysical Phenomena · Physics 2017-01-12 Mariangela Lisanti , Siddharth Mishra-Sharma , Lina Necib , Benjamin R. Safdi

We present a statistical framework which can be used to determine the contribution of an unresolved population of pulsars to the gamma-ray background. This formalism is based on the joint analysis of photon time series over extended regions…

High Energy Astrophysical Phenomena · Physics 2012-03-20 Alex Geringer-Sameth , Savvas M. Koushiappas

There is active interest in the extent to which unresolved gamma-ray pulsars contribute to the galactic diffuse emission, and whether unresolved gamma-ray pulsars could be responsible for the excess of diffuse galactic emission above 1 GeV…

Astrophysics · Physics 2007-05-23 Martin Pohl , Gottfried Kanbach , Stan D. Hunter , Brian B. Jones

We provide conservative bounds on the dark matter cross-section and lifetime from final state radiation produced by annihilation or decay into charged leptons, either directly or via an intermediate particle $\phi$. Our analysis utilizes…

High Energy Physics - Phenomenology · Physics 2009-09-04 Rouven Essig , Neelima Sehgal , Louis E. Strigari

Recently, two nearby prominent starburst galaxies, M82 and NGC253, have been detected as point-like sources with gamma-ray telescopes at TeV energies [1] [2]. It has been claimed that these detections show that the cosmic ray intensity in…

High Energy Astrophysical Phenomena · Physics 2010-10-13 O. Tibolla , K. Mannheim , D. Elsässer

We estimate the conventional astrophysical emission from dwarf spheroidal satellite galaxies (dSphs) of the Milky Way, focusing on millisecond pulsars (MSPs), and evaluate the potential for confusion with dark matter (DM) annihilation…

High Energy Astrophysical Phenomena · Physics 2016-11-15 Miles Winter , Gabrijela Zaharijas , Keith Bechtol , Justin Vandenbroucke