English
Related papers

Related papers: Diffuse Gamma-Ray Emission from Starburst Galaxies…

200 papers

We present an analysis of COMPTEL observations made between November 1991 and May 1994 of 2CG 135+01, a bright gamma-ray source located near the Galactic plane. At energies above 1 MeV, an excess consistent with the position of 2CG 135+01…

Here we review our current knowledge on diffuse gamma-rays from galactic halos. Estimates of the relative contribution of the various emission processes at low and high latitudes are compared to the data over 6 decades in energy. The…

Astrophysics · Physics 2007-05-23 M. Pohl

Observations by the Fermi-LAT have uncovered a bright, spherically symmetric excess surrounding the center of the Milky Way galaxy. The spectrum of the gamma-ray excess peaks sharply at an energy ~2 GeV, exhibiting a hard spectrum at lower…

High Energy Astrophysical Phenomena · Physics 2017-02-28 Tim Linden , Nicholas L. Rodd , Benjamin R. Safdi , Tracy R. Slatyer

Recently the Milagro experiment observed diffuse multi-TeV gamma-ray emission in the Cygnus region, which is significantly stronger than what predicted by the Galactic cosmic ray model. However, the sub-GeV observation by EGRET shows no…

Astrophysics · Physics 2009-06-23 Xiao-Jun Bi , Tian-Lu Chen , Yue Wang , Qiang Yuan

The Energetic Gamma-Ray Experiment Telescope (EGRET) experiment onboard the Compton Gamma-Ray Observatory (CGRO) has provided the most precise measurements of the gamma-ray sky to date. The EGRET measurements of the diffuse emission across…

Astrophysics · Physics 2007-06-05 B. M. Baughman , W. B. Atwood , R. P. Johnson , T. A. Porter , M. Ziegler

Observations of diffuse Galactic gamma-ray spectrum by the EGRET instrument reveal an excess above ~ 1 GeV over the expected gamma-ray spectrum calculated under the assumption that the locally observed cosmic-ray (CR) spectra represent the…

Astrophysics · Physics 2009-11-11 Thoudam Satyendra

An extinction distribution of the Andromeda Galaxy (M31) is constructed with member stars as tracers by fitting multiband photometric data from UKIRT/WFCAM, PS1, and Gaia DR3. The resulting extinction distribution covers approximately 10…

Astrophysics of Galaxies · Physics 2025-03-25 Yuxi Wang , Jian Gao , Yi Ren , Bingqiu Chen

In the course of its operation, the EGRET experiment detected high-energy gamma ray sources at energies above 100 MeV over the whole sky. In this communication, we search for large-scale anisotropy patterns among the catalogued EGRET…

Astrophysics · Physics 2007-05-23 Luis Anchordoqui , Thomas McCauley , Thomas Paul , Olaf Reimer , Diego F. Torres

Starburst galaxies are undergoing intense episodes of star formation. In these galaxies, gas is ejected into the surrounding environment through winds created by the effect of hot stars and supernova explosions. When interacting with the…

Astrophysics of Galaxies · Physics 2024-03-12 C. A. Galante , J. Saponara , G. E. Romero , P. Benaglia

We have mapped four regions of the southern Galactic plane at 31 GHz with the Cosmic Background Imager. From the maps, we have extracted the flux densities for six of the brightest \hii regions in the southern sky and compared them with…

We report on the detection of a gamma-ray source at the position of the nearby star-forming galaxy (SFG) M83, which is found from our analysis of 14 years of the data obtained with the Large Area Telescope (LAT) on-board {\it Fermi…

High Energy Astrophysical Phenomena · Physics 2023-08-02 Yi Xing , Zhongxiang Wang

One of the most prominent features of the $\gamma$-ray sky is the emission from our own Galaxy. The Galactic plane has been observed by Fermi-LAT in GeV and H.E.S.S. in TeV light. Fermi has modeled the Galactic emission as the sum of a…

High Energy Astrophysical Phenomena · Physics 2015-06-09 Ellis Owen , Christoph Deil , Axel Donath , Régis Terrier

The nearby dwarf spheroidal galaxy Draco with its high mass to light ratio is one of the most auspicious targets for indirect dark matter searches. Annihilation of hypothetical DM particles can result in high-energy gamma-rays, e.g. from…

Astrophysics · Physics 2008-11-26 MAGIC Collaboration , J. Albert

We present a systematic search for short-duration gamma-ray bursts (GRBs) in the local Universe based on 14 years of observations with the Neil Gehrels Swift Observatory. We cross-correlate the GRB positions with the GLADE catalogue of…

High Energy Astrophysical Phenomena · Physics 2020-02-12 S. Dichiara , E. Troja , B. O'Connor , F. E. Marshall , P. Beniamini , J. K. Cannizzo , A. Y. Lien , T. Sakamoto

2 years worth of archival FERMI-LAT data was used to search for the gamma-ray emission from the Andromeda galaxy. The data show no noticeable elliptical image. Subsequent on-off source aperture photometry analysis using a CO image template…

High Energy Astrophysical Phenomena · Physics 2015-05-19 H. Ögelman , N. Aksaker , S. Anılan , H. Dereli , N. Emrahoğlu , I. Yegingil

We present results from {\gamma}-ray observations of the Coma cluster incorporating 6 years of Fermi-LAT data and the newly released {\emph{Pass 8}} event-level analysis. Our analysis of the region reveals low-significance residual…

High Energy Astrophysical Phenomena · Physics 2016-03-10 LAT Collaboration , Y. Rephaeli

We discuss the production of $\gamma$-rays from cosmic rays (CR) in the circumgalactic medium (CGM) of Andromeda (M31) in light of the recent detection of $\gamma$-rays from an annular region of $\sim 5.5-120$ kpc away from the M31 disc. We…

Astrophysics of Galaxies · Physics 2022-06-08 Manami Roy , Biman B. Nath

We present spatially-resolved spectroscopy from the Keck Cosmic Web Imager (KCWI) of a star-forming galaxy at z=0.6942, which shows emission from the Mg II 2796, 2803 Angstrom doublet in the circumgalactic medium (CGM) extending ~37 kpc at…

Structure formation in the universe can produce high energy gamma-rays from shock-accelerated electrons, and this process may be the origin of the extragalactic gamma-ray background (EGRB) as well as a part of the unidentified sources…

Astrophysics · Physics 2009-11-06 Tomonori Totani , Susumu Inoue

The HEGRA-IACT-system with a FoV of ~1.5 deg radius has been used for surveying one quater of the Galactic disc in respect to point sources, moderately extended sources and for diffuse emission in the energy range above 1 TeV. In total 140…

‹ Prev 1 3 4 5 6 7 10 Next ›