English
Related papers

Related papers: Molecular Clouds as the Origin of the Fermi Gamma-…

200 papers

Recently, tentative evidence for an excess of gamma rays at energies around 130 GeV has been reported from analyses of data from the Fermi Large Area Telescope (LAT). The excess is potentially of great interest, as it could be associated…

High Energy Astrophysical Phenomena · Physics 2012-07-04 Stefano Profumo , Tim Linden

An anomalous gamma-ray excess emission has been found in Fermi Large Area Telescope data covering the centre of the Galaxy. Several theories have been proposed for this `Galactic Centre Excess'. They include self-annihilation of dark matter…

High Energy Astrophysical Phenomena · Physics 2023-08-10 Oscar Macias , Chris Gordon , Roland M. Crocker , Brenna Coleman , Dylan Paterson , Shunsaku Horiuchi , Martin Pohl

We construct empirical models of the diffuse gamma-ray background toward the Galactic Center. Including all known point sources and a template of emission associated with interactions of cosmic rays with molecular gas, we show that the…

High Energy Astrophysical Phenomena · Physics 2014-07-23 Kevork N. Abazajian , Nicolas Canac , Shunsaku Horiuchi , Manoj Kaplinghat

Observations of very-high-energy (VHE) gamma-ray emission from supernova remnants (SNR) established them as sources of accelerated particles up to energies of 100 TeV. The dominant process - leptonic or hadronic - responsible for the VHE…

High Energy Astrophysical Phenomena · Physics 2013-07-23 Stephanie Häffner , Ira Jung , Christian Stegmann

From astronomical observations, we know that dark matter exists and makes up $\sim$25\% of our Universe. Recently the study of anomalous gamma-ray emission in the regions surrounding the galactic center has drawn a lot of attention. It has…

High Energy Physics - Phenomenology · Physics 2015-07-08 Tanmoy Mondal , Tanushree Basak

The Galactic Center Gamma-Ray Excess has a spectrum, angular distribution, and overall intensity that agree remarkably well with that expected from annihilating dark matter particles in the form of a $m_X \sim 50 \, {\rm GeV}$ thermal…

High Energy Astrophysical Phenomena · Physics 2022-09-30 Dan Hooper

The High-Energy Stereoscopic System (HESS) has detected diffuse TeV emission correlated with the distribution of molecular gas along the Ridge at the Galactic Center. Diffuse, non-thermal emission is also seen by the Fermi large area…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Oscar Macias , Chris Gordon , Roland Crocker , Stefano Profumo

The region surrounding the center of the Milky Way is both astrophysically rich and complex, and is predicted to contain very high densities of dark matter. Utilizing three years of data from the Fermi Gamma Ray Space Telescope (and the…

High Energy Astrophysical Phenomena · Physics 2013-05-29 Dan Hooper , Tim Linden

The diffuse Galactic gamma-ray background, as observed with EGRET on CGRO, exceeds the model predictions significantly above 1 GeV. This is particularly true for the inner Galaxy. We shall discuss here the contribution of the Galactic…

Astrophysics · Physics 2009-10-31 Heinz Voelk

An excess of gamma rays at GeV energies has been pointed out in the Fermi-LAT data. This signal comes from a narrow region centred around the Galactic center and has been interpreted as possible evidence for light dark matter particles…

High Energy Astrophysical Phenomena · Physics 2014-08-13 Thomas Lacroix , Celine Boehm , Joseph Silk

In this article, I summarize and discuss the body of evidence which has accumulated in favor of dark matter in the form of approximately 10 GeV particles. This evidence includes the spectrum and angular distribution of gamma rays from the…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-09 Dan Hooper

In this work, we revisit the all-sky Galactic diffuse $\gamma$-ray emission taking into account the new measurements of cosmic ray electron/positron spectrum by PAMELA, ATIC and Fermi, which show excesses of cosmic electrons/positrons…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Juan Zhang , Qiang Yuan , Xiao-Jun Bi

We analyze the processes governing cosmic-ray (CR) penetration into molecular clouds and the resulting generation of gamma-ray emission. The density of CRs inside a cloud is depleted at lower energies due to the self-excited MHD turbulence.…

High Energy Astrophysical Phenomena · Physics 2018-12-05 V. A. Dogiel , D. O. Chernyshov , A. V. Ivlev , D. Malyshev , A. W. Strong , K. S. Cheng

A number of Galactic sources emit GeV-TeV gamma rays that are produced through leptonic and/or hadronic mechanisms. Spectral analysis in this energy range is crucial in order to understand the emission mechanisms. The HAWC Gamma-Ray…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Hao Zhou , C. Michelle Hui , Petra Huentemeyer

The apparent gamma-ray excess in the Galactic center region and inner Galaxy has attracted considerable interest, notably because both its spectrum and radial distribution are consistent with an interpretation in terms of annihilating dark…

High Energy Astrophysical Phenomena · Physics 2014-12-03 Torsten Bringmann , Martin Vollmann , Christoph Weniger

The center of the Milky Way is offering one of the most striking mystery in Astroparticle Physics. An excess of gamma rays (GCE) has been measured by several groups in the data collected by the Fermi Large Area Telescope (LAT) towards the…

High Energy Astrophysical Phenomena · Physics 2020-11-18 Mattia Di Mauro

Molecular clouds are expected to emit non-thermal radiation due to cosmic ray interactions in the dense magnetized gas. Such emission is amplified if a cloud is located close to an accelerator of cosmic rays and if energetic particles can…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Stefano Gabici , Felix A. Aharonian , Sabrina Casanova

The two most favored explanations of the Fermi Galactic Center gamma-ray excess (GCE) are millisecond pulsars and self annihilation of the smooth dark matter halo of the galaxy. In order to distinguish between these possibilities, we would…

High Energy Astrophysical Phenomena · Physics 2024-07-29 Katharena Christy , Eric J. Baxter , Jason Kumar

The origin of the inner Galactic emission, measured by COMPTEL with a flux of $\sim ~ 10^{-2}$ MeV cm$^{-2}$ s$^{-1}$ sr$^{-1}$ in the 1-30 MeV range, has remained unsettled since its discovery in 1994. We investigate the origin of this…

High Energy Astrophysical Phenomena · Physics 2023-06-02 Naomi Tsuji , Yoshiyuki Inoue , Hiroki Yoneda , Reshmi Mukherjee , Hirokazu Odaka

An excess of $\gamma$ rays in the data measured by the Fermi Large Area Telescope in the direction of the Galactic center has been reported in several publications. This excess, labeled as the Galactic center excess (GCE), is detected…

High Energy Astrophysical Phenomena · Physics 2021-06-09 Mattia Di Mauro , Martin Wolfgang Winkler