English
Related papers

Related papers: The interstellar environment in the outer Galaxy a…

200 papers

A spherical-symmetric gamma-ray emission from the central region of the Galaxy has been recently identified in Fermi-LAT data, and initially associated to dark matter particle annihilations. Guided by the evidence for a high gas density in…

High Energy Astrophysical Phenomena · Physics 2016-01-13 Daniele Gaggero , Marco Taoso , Alfredo Urbano , Mauro Valli , Piero Ullio

We present quantitative statistical evidence for a $\gamma$-ray emission halo surrounding the Galaxy. Maps of the emission are derived. EGRET data were analyzed in a wavelet-based non-parametric hypothesis testing framework, using a model…

The Fermi LAT has opened the way for comparative studies of cosmic rays (CRs) and high-energy objects in the Milky Way (MW) and in other, external, star-forming galaxies. Using 2 yr of observations with the Fermi LAT, local Group galaxy M31…

High Energy Astrophysical Phenomena · Physics 2017-03-01 LAT Collaboration

{\it Fermi}-LAT has recently detected two gamma ray bubbles disposed symmetrically with respect to the Galactic plane. The bubbles have been suggested to be in a quasi-steady state, inflated by ongoing star formation over the age of the…

Astrophysics of Galaxies · Physics 2015-05-28 K. Zubovas , A. R. King , S. Nayakshin

With a decade of gamma-ray data from the Fermi-LAT telescope, we can now hope to answer how well we know the local Universe at gamma-ray frequencies. On the other hand, with gamma-ray data alone it is not possible to directly access the…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-27 Simone Ammazzalorso , Nicolao Fornengo , Shunsaku Horiuchi , Marco Regis

We calculate the gamma-ray albedo due to cosmic-ray interactions with debris (small rocks, dust, and grains) in the Oort Cloud. We show that under reasonable assumptions a significant proportion of what is called the "extragalactic…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Igor V. Moskalenko , Troy A. Porter

High-energy gamma-ray emission from the Galactic plane above ~100 MeV is composed of three main contributions: diffuse emission from cosmic ray interactions in the interstellar medium, emission from extended sources, such as supernova…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Neronov , D. Malyshev , M. Chernyakova , A. Lutovinov

Population studies of unidentified EGRET sources suggest that there exist at least three different populations of galactic gamma-ray sources. One of these populations is formed by young objects distributed along the galactic plane with a…

Astrophysics · Physics 2009-11-10 V. Bosch-Ramon , G. E. Romero , J. M. Paredes

We present the analysis of the interstellar gamma-ray emission measured by the Fermi Large Area Telescope toward a region in the second Galactic quadrant at 100 deg < l < 145 deg and -15 deg < b < +30 deg. This region encompasses the…

High Energy Astrophysical Phenomena · Physics 2014-11-20 LAT collaboration

A crucial process in Galactic cosmic-ray (CR) transport is the spatial diffusion due to the interaction with the interstellar turbulent magnetic field. Usually, CR diffusion is assumed to be uniform and isotropic all across the Galaxy.…

High Energy Astrophysical Phenomena · Physics 2017-10-25 Silvio Sergio Cerri , Daniele Gaggero , Andrea Vittino , Carmelo Evoli , Dario Grasso

Galactic interstellar emission contributes substantially to Fermi LAT observations in the Galactic plane, where the majority of Supernova Remnants (SNRs) are located. We have developed a method to explore some systematic effects on SNRs'…

High Energy Astrophysical Phenomena · Physics 2019-08-13 F. de Palma , T. J. Brandt , G. Johannesson , L. Tibaldo

The possible gamma-ray excess in the inner Galaxy and the Galactic center (GC) suggested by Fermi-LAT observations has triggered a large number of studies. It has been interpreted as a variety of different phenomena such as a signal from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Francesca Calore , Ilias Cholis , Christoph Weniger

The Cygnus region hosts a giant molecular-cloud complex which actively forms massive stars. Interactions of cosmic rays with interstellar gas and radiation fields make it shine at gamma-ray energies. Several gamma-ray pulsars and other…

High Energy Astrophysical Phenomena · Physics 2012-08-27 the Fermi LAT Collaboration

We present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend…

High Energy Astrophysical Phenomena · Physics 2017-07-27 D. Gaggero , D. Grasso , A. Marinelli , M. Taoso , A. Urbano , S. Ventura

Observations using the Fermi Large Area Telescope (Fermi-LAT) have found a significant gamma-ray excess surrounding the center of the Milky Way (GC). One possible interpretation of this excess invokes gamma-ray emission from an undiscovered…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Tim Linden

The Andromeda Galaxy is the closest spiral galaxy to us and has been the subject of numerous studies. It harbors a massive dark matter (DM) halo which may span up to ~600 kpc across and comprises ~90% of the galaxy's total mass. This halo…

High Energy Astrophysical Phenomena · Physics 2019-08-07 Chris Karwin , Simona Murgia , Sheldon Campbell , Igor Moskalenko

A majority of the $\gamma$-ray emission from star-forming galaxies is generated by the interaction of high-energy cosmic rays with the interstellar gas and radiation fields. Star-forming galaxies are expected to contribute to both the…

Astrophysics of Galaxies · Physics 2020-05-20 M. Ajello , M. Di Mauro , V. S. Paliya , S. Garrappa

We study a scenario in which the Fermi bubbles are formed through a Galactocentric outflow of gas and pre-accelerated cosmic-rays (CR). We take into account CR energy losses due to proton-proton interactions with the gas present in the…

High Energy Astrophysical Phenomena · Physics 2018-10-29 Gwenael Giacinti , Andrew M. Taylor

Diffuse galactic gamma-ray emission is produced by the interaction of cosmic rays (CRs) with the interstellar environment. The study of gamma-ray emission is therefore a powerful tool to investigate the origin of CRs and the processes…

High Energy Astrophysical Phenomena · Physics 2018-07-18 N. Marchili , G. Piano , M. Cardillo , A. Giuliani , S. Molinari , M. Tavani

The Galactic gamma-ray diffuse emission is currently observed in the GeV-TeV energy range with unprecedented accuracy by the Fermi satellite. Understanding this component is crucial as it provides a background to many different signals such…

High Energy Astrophysical Phenomena · Physics 2015-03-18 Timur Delahaye , Armand Fiasson , Martin Pohl , Pierre Salati
‹ Prev 1 4 5 6 7 8 10 Next ›