English
Related papers

Related papers: Modelling the broadband emission from the white dw…

200 papers

Since the detection of very high energy (VHE) $\gamma$-rays from Mrk 501, its broad band emission of radiation was mostly and quite effectively modeled using one zone emission scenario. However, broadband spectral and flux variability…

High Energy Astrophysical Phenomena · Physics 2015-03-11 A. Shukla , V. R. Chitnis , B. B. Singh , B. S. Acharya , G. C. Anupama , P. Bhattacharjee , R. J. Britto , K. Mannheim , T. P. Prabhu , L. Saha , P. R. Vishwanath

The mm to sub-mm spectrum of Sgr A* at the Galactic center, as well as its polarization characteristics, are consistent with the inner 10 Schwarzschild radii of a tight Keplerian emitting region of hot, magnetized, orbiting gas. This plasma…

Astrophysics · Physics 2009-11-07 Siming Liu , Fulvio Melia

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We have analyzed a comprehensive submillimeter (including new observations simultaneous with…

Circinus galaxy is a nearby composite starburst/AGN system. In this work we re-analyze the GeV emission from Circinus with 10 years of {\it Fermi}-LAT Pass 8 data. In the energy range of 1-500 GeV, the spectrum can be well fitted by a…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Xiao-Lei Guo , Yu-Liang Xin , Neng-Hui Liao , Yi-Zhong Fan

We have investigated the empirical lag-luminosity relation in the Gamma-ray Burst (GRB) source-frame. We selected two energy bands (100-200 keV and 300-400 keV) in the GRB source-frame, which after redshift correction, lie in the…

High Energy Astrophysical Phenomena · Physics 2010-03-02 T. N. Ukwatta , K. S. Dhuga , M. Stamatikos , T. Sakamoto , W. C. Parke , S. D. Barthelmy , N. Gehrels

We have performed monitoring observations of the flux density toward the Galactic center compact radio source, Sagittarius A* (Sgr A*), which is a supermassive black hole, from 1996 to 2005 using the Nobeyama Millimeter Array of the…

The MAGIC collaboration has recently reported correlated X-ray and very high-energy gamma-ray emission from the gamma-ray binary LS I +61 303 during ~60% of one orbit. These observations suggest that the emission in these two bands has its…

High Energy Astrophysical Phenomena · Physics 2015-03-17 V. Zabalza , J. M. Paredes , V. Bosch-Ramon

All known Small Solar System Bodies have diameters between a few meters and a few thousands of kilometers. Based on the collisional evolution of Solar System Bodies, a larger number of asteroids with diameters down to $\sim 2$ m is thought…

High Energy Astrophysical Phenomena · Physics 2023-07-05 S. De Gaetano , L. Di Venere , F. Gargano , F. Loparco , L. Lorusso , M. N. Mazziotta , G. Panzarini , R. Pillera , D. Serini

We perform a comprehensive stacking analysis of data collected by the Fermi Large Area Telescope (LAT) of gamma-ray bursts (GRB) localized by the Swift spacecraft, which were not detected by the LAT but which fell within the instrument's…

High Energy Astrophysical Phenomena · Physics 2016-05-10 LAT Collaboration

We present detailed observations of the bright short-hard gamma-ray burst GRB 090510 made with the Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) on board the Fermi observatory. GRB 090510 is the first burst detected by the…

High Energy Astrophysical Phenomena · Physics 2015-03-17 The Fermi LAT , GBM Collaborations

Recent advances in the $\gamma$-ray observations of solar flares by the \textit{Fermi} satellite, demand revisions in the hadronic $\gamma$-ray flux computation below 1 GeV. In this work we utilize recently updated pion production cross…

High Energy Astrophysical Phenomena · Physics 2018-09-19 Ervin Kafexhiu , Carlo Romoli , Andrew M. Taylor , Felix Aharonian

Using 15 years of data from the Fermi Large Area Telescope (Fermi-LAT), we performed a comprehensive analysis on the gamma-ray binary HESS J0632+057. Its spectrum in 0.1-300 GeV band is well described by a power law model with an index of…

High Energy Astrophysical Phenomena · Physics 2025-04-24 Yanlv Yang , Dengke Zhou , Zihao Zhao , Jian Li , Diego F. Torres , Pei Wang

The flux of positrons and electrons ($e^+ + e^-$) has been measured by the $Fermi$ Large Area Telescope (LAT) in the energy range between 7 GeV and 2 TeV. We discuss a number of interpretations of Pass 8 $Fermi$-LAT $e^+ + e^-$ spectrum,…

The diffuse continuum emission from the Galactic plane in the energy range 18-1000 keV has been studied using 16 Ms of data from the SPI instrument on INTEGRAL. With such an exposure we can exploit the imaging properties of SPI to achieve a…

Astrophysics · Physics 2007-05-23 A. W. Strong , R. Diehl , H. Halloin , V. Schoenfelder , L. Bouchet , P. Mandrou , F. Lebrun , R. Terrier

Context: Colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Observation of synchrotron radiation in the radio band confirms there is…

High Energy Astrophysical Phenomena · Physics 2013-08-13 M. Werner , O. Reimer , A. Reimer , K. Egberts

The radio, optical, and $\gamma$-ray light curves of the blazar S5 1803+784, from the beginning of the {\it Fermi} Large Area Telescope (LAT) mission in August 2008 until December 2018, are presented. The aim of this work is to look for…

High Energy Astrophysical Phenomena · Physics 2021-03-03 R. Nesci , S. Cutini , C. Stanghellini , F. Martinelli , A. Maselli , V. M. Lipunov , V. Kornilov , R. R. Lopez , A. Siviero , M. Giroletti , M. Orienti

Fermi has provided the largest sample of {\gamma}-ray selected blazars to date. In this work we use a complete sample of FSRQs detected during the first year of operation to determine the luminosity function (LF) and its evolution with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 M. Ajello , M. S. Shaw , R. W. Romani , C. D. Dermer , L. Costamante , O. G. King , W. Max-Moerbeck , A. Readhead , A. Reimer , J. L. Richards , M. Stevenson

We report on gamma-ray observations of the supernova remnant (SNR) RX J0852.0-4622 with the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope. In the Fermi LAT data, we find a spatially extended source at the location of…

High Energy Astrophysical Phenomena · Physics 2011-10-06 T. Tanaka , A. Allafort , J. Ballet , S. Funk , F. Giordano , J. Hewitt , M. Lemoine-Goumard , H. Tajima , O. Tibolla , Y. Uchiyama

The preliminary detection of the Galactic Center black hole Sgr A* in X-rays by the Chandra mission, as well as recent mm-VLBI measurements, impose strict constraints on this source. Using a relativistic jet model for Sgr A*, we calculate…

Astrophysics · Physics 2011-05-05 Heino Falcke , Sera Markoff

The Fermi Large Area Telescope (Fermi-LAT) has recently revealed a large population of gamma-ray emitting millisecond pulsars (MSPs) in our Galaxy. We aim to infer the properties of the Galactic population of gamma-ray emitting MSPs from…

Astrophysics of Galaxies · Physics 2015-06-15 Tristan Grégoire , Jürgen Knödlseder
‹ Prev 1 8 9 10 Next ›