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The Physics of Transient High-Energy Cosmic Sources: from Radio to VHE Gamma-rays [PDF]

open access: goldProceedings of XI Multifrequency Behaviour of High Energy Cosmic Sources Workshop — PoS(MULTIF15), 2016
P. J. Meintjes
openalex   +2 more sources

SMM Observations of Gamma-Ray Transients. I. A Search for Variable Emission at MeV Energies from Five Galactic and Extragalactic Sources

open access: closedThe Astrophysical Journal, 1993
Transient emission at energies near 1 MeV has been reported by previous experiments on time scales of weeks to months from the Galactic center, the Crab Nebula, and Cyg X-1, and on shorter time-scales from NGC 4151 and Cen A. The spectra of these events call into two broad classes: a broad line-like feature centered near 1 MeV, and continuum emission ...
Mark Harris   +3 more
openalex   +3 more sources

On the Properties of Inverse Compton Spectra Generated by Upscattering a Power-law Distribution of Target Photons

open access: yesThe Astrophysical Journal, 2023
Relativistic electrons are an essential component in many astrophysical sources, and their radiation may dominate the high-energy bands. Inverse Compton (IC) emission is the radiation mechanism that plays the most important role in these bands. The basic
Dmitry Khangulyan   +2 more
doaj   +1 more source

Evidence for Two Distinct Populations of Kilonova-associated Gamma-Ray Bursts

open access: yesThe Astrophysical Journal Letters, 2023
Identification of gamma-ray burst (GRB) progenitors based on the duration of their prompt emission ( T _90 ) has faced several roadblocks recently. Long-duration GRBs (with T _90 > 2 s) have traditionally been thought to be originating from the collapse ...
Dimple, K. Misra, K. G. Arun
doaj   +1 more source

GRB 221009A: The BOAT

open access: yesThe Astrophysical Journal Letters, 2023
GRB 221009A has been referred to as the brightest of all time (BOAT). We investigate the veracity of this statement by comparing it with a half century of prompt gamma-ray burst observations.
Eric Burns   +29 more
doaj   +1 more source

The Jet Opening Angle and Event Rate Distributions of Short Gamma-Ray Bursts from Late-time X-Ray Afterglows

open access: yesThe Astrophysical Journal, 2023
We present a comprehensive study of 29 short gamma-ray bursts (SGRBs) observed ≈0.8−60 days postburst using Chandra and XMM-Newton. We provide the inferred distributions of the SGRB jet opening angles and true event rates to compare against neutron star ...
A. Rouco Escorial   +16 more
doaj   +1 more source

Transient sources with LST-1: study of novae, supernovae, and gamma-ray bursts

open access: closed
[eng] The branch of astrophysics that studies transient phenomena allows the exploration of astronomical sources that show temporal variability that can extend from a few fractions of a second to scales as long as tens of years. These transient events can give rise to a wide variety of phenomena observed throughout the electromagnetic spectrum. In some
Aguasca i Cabot, Arnau
openalex   +2 more sources

Discovery of a transient MeV range gamma-ray source

open access: yesThe Astrophysical Journal, 1995
The University of California, San Diego (UCSD)/MIT hard X-ray and gamma-ray instrument on the HEAO 1 surveyed the region near the Galactic center 3 times during its lifetime in 1977-1979. During the 1977 September-October scan, a gamma-ray source was detected south of the Galactic center. The source was below the threshold sensitivity in the spring and
M. S. Briggs   +3 more
openaire   +1 more source

Hybrid Emission Modeling of GRB 221009A: Shedding Light on TeV Emission Origins in Long GRBs

open access: yesThe Astrophysical Journal, 2023
Observations of long-duration gamma-ray bursts (GRBs) with TeV emission during their afterglow have been on the rise. Recently, GRB 221009A, the most energetic GRB ever observed, was detected by the Large High Altitude Air Shower Observatory experiment ...
Hebzibha Isravel   +2 more
doaj   +1 more source

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