Results 121 to 130 of about 479,061 (218)
Blazar jet physics in the age of Fermi [PDF]
The impact of the Fermi Gamma-ray Space Telescope on blazar research is reviewed. This includes a brief description of the Fermi Large Area Telescope, a summary of the various classes of extragalactic sources found in the First Large Area Telescope AGN Catalog, and more detailed discussion of the flat spectrum radio quasar 3C454.3 and the BL Lac object
arxiv +1 more source
The Cross-Calibration of Swift-BAT and Fermi-GBM via Correlative Spectral Analysis of GRBs [PDF]
We report on recent inter-calibration studies featuring Swift's Burst Alert Telescope (BAT) and Fermi's Gamma-ray Burst Monitor (GBM) based upon correlated observations of GRBs 080804 and 080810, via their resultant joint spectral analysis. Swift's intrinsic multi-wavelength instrumentation and dynamical response complement Fermi's superior energy ...
arxiv
Revisiting γ-Ray Emission of the Supernova Remnant RCW 103
We analyze more than 15 yr of γ -ray data obtained with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) for the region of the young supernova remnant (SNR) RCW 103, since the nearby source 4FGL J1616.2−5054e ...
Yi Xing, Zhongxiang Wang, Dong Zheng
doaj +1 more source
Fermi Observations of the Large Magellanic Cloud [PDF]
We report on observations of the Large Magellanic Cloud with the Fermi Gamma-Ray Space Telescope. The LMC is clearly detected with the Large Area Telescope (LAT) and for the first time the emission is spatially well resolved in gamma-rays. Our observations reveal that the bulk of the gamma-ray emission arises from the 30 Doradus region. We discuss this
arxiv
Pre-burst events of gamma-ray bursts with light speed variation
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
Monitoring the Gamma-ray Sky through 4.5 Years of Fermi LAT Flare Advocate Service [PDF]
The Fermi Flare Advocate (also known as Gamma-ray Sky Watcher, FA-GSW) service provides for a quick look and review of the gamma-ray sky observed daily by the Fermi Large Area Telescope (LAT). The FA-GSW service provides alerts and communicates to the external scientific community potentially new gamma-ray sources, interesting transients and source ...
arxiv
"Fermi" bubbles are bursting from our galaxy. Their origins remain a mystery. [PDF]
Mann A.
europepmc +1 more source
Upper limit on the axion-photon coupling from Markarian 421
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
Prompt optical observations of Fermi-LAT bursts and GRB 090902B [PDF]
Observations of high energy emission from gamma-ray bursts (GRBs) constrain the extreme physical conditions associated with these energetic cosmic explosions. The Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope, a pair conversion telescope, observes energetic quanta from 30 MeV to > 300 GeV.
arxiv
Pre-burst neutrinos of gamma-ray bursters accompanied by high-energy photons
Previous researches on high-energy neutrino events from gamma-ray bursters (GRBs) suggest a neutrino speed variation v(E)=c(1±E/ELVν) with ELVν=(6.4±1.5)×1017 GeV, together with an intrinsic time difference Δtin=(−2.8±0.7)×102 s, which means that high ...
Jie Zhu, Bo-Qiang Ma
doaj