Results 1 to 10 of about 26,003 (179)

Fundamental physics in space with the Fermi Gamma-ray Space Telescope [PDF]

open access: yesJournal of Physics: Conference Series, 2011
Successfully launched in June 2008, the Fermi Gamma-ray Space Telescope, formerly named GLAST, has been observing the high-energy gamma-ray sky with unprecedented sensitivity for more than two years, opening a new window on a wide variety of exotic ...
L. Baldini
semanticscholar   +5 more sources

Dark Matter Signals in the gamma-ray sky

open access: yesEPJ Web of Conferences, 2014
Detection of gamma rays and cosmic rays from the annihilation or decay of dark matter particles is a promising method for identifying dark matter, understanding its intrinsic properties, and mapping its distribution in the universe.
Morselli Aldo
doaj   +1 more source

On the Gamma-Ray Emission of the Andromeda Galaxy M31

open access: yesThe Astrophysical Journal Letters, 2023
Using the γ -ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi) for ∼14 yr, we examine the high-energy emission emanating from the center of the Andromeda galaxy M31.
Yi Xing   +3 more
doaj   +1 more source

Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi

open access: yes, 2009
We report the detection of high-energy gamma-ray emission from two starburst galaxies using data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope.
Abdo, AA   +169 more
core   +3 more sources

Pre-burst events of gamma-ray bursts with light speed variation

open access: yesPhysics Letters B, 2021
Previous researches on high-energy photon events from gamma-ray bursts (GRBs) suggest a light speed variation v(E)=c(1−E/ELV) with ELV=3.6×1017 GeV, together with a pre-burst scenario that hight-energy photons come out about 10 seconds earlier than low ...
Jie Zhu, Bo-Qiang Ma
doaj   +1 more source

Upper limit on the axion-photon coupling from Markarian 421

open access: yesPhysics Letters B
Markarian421 is a well-known nearby BL Lac blazar at the redshift z=0.031. Many previous works were investigated to constrain the axion-photon coupling from its TeV gamma-ray observations, showing the upper limit on the coupling constant gaγ≲2.0×10−11GeV−
Hai-Jun Li, Wei Chao, Yu-Feng Zhou
doaj   +1 more source

Relativistic Jets in Gamma-Ray-Emitting Narrow-Line Seyfert 1 Galaxies

open access: yesGalaxies, 2019
Before the launch of the Fermi Gamma-ray Space Telescope satellite only two classes of active galactic nuclei (AGN) were known to generate relativistic jets and thus to emit up to the γ -ray energy range: blazars and radio galaxies, both hosted
Filippo D’Ammando
doaj   +1 more source

The multi-faceted synergy between Swift and Fermi in radio-loud AGN studies

open access: yes, 2015
Since its launch in 2008 June, the Fermi Gamma-ray Space Telescope has opened a new era in high-energy astrophysics. The unprecedented sensitivity, angular resolution and effective area of the Large Area Telescope on board Fermi, together with the nearly
D'Ammando, F.
core   +1 more source

Radio/gamma-ray time delay in the parsec-scale cores of active galactic nuclei [PDF]

open access: yes, 2010
We report the detection of a non-zero time delay between radio emission measured by the VLBA at 15.4 GHz and gamma-ray radiation (gamma-ray leads radio) registered by the Large Area Telescope (LAT) on board the Fermi Gamma-Ray Space Telescope for a ...
Abdo   +19 more
core   +3 more sources

Unraveling the Physics of Quasar Jets: Optical Polarimetry and Implications for the X-ray Emission Process

open access: yesGalaxies, 2020
Since the launch of Chandra twenty years ago, one of the greatest mysteries surrounding Quasar Jets is the production mechanism for their extremely high X-ray luminosity. Two mechanisms have been proposed. In the first view, the X-ray emission is inverse-
Eric S. Perlman   +6 more
doaj   +1 more source

Home - About - Disclaimer - Privacy