Results 11 to 20 of about 712,854 (335)

Limits on Leptonic TeV Emission from the Cygnus Cocoon with Swift-XRT

open access: yesThe Astrophysical Journal, 2023
γ -ray observations of the Cygnus Cocoon, an extended source surrounding the Cygnus X star-forming region, suggest the presence of a cosmic-ray accelerator reaching energies up to a few PeV.
David Guevel   +7 more
doaj   +1 more source

Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth [PDF]

open access: yesScience, 2017
Exotic origin for cosmic positrons Several cosmic-ray detectors have found more positrons arriving at Earth than expected. Some researchers interpret this as a signature of exotic physics, such as the annihilation of dark matter particles.
A. Abeysekara   +115 more
semanticscholar   +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

Classification of New X-Ray Counterparts for Fermi Unassociated Gamma-Ray Sources Using the Swift X-Ray Telescope [PDF]

open access: yesAstrophysical Journal, 2019
Approximately one-third of the gamma-ray sources in the third Fermi-LAT catalog are unidentified or unassociated with objects at other wavelengths. Observations with the X-Ray Telescope on the Neil Gehrels Swift Observatory (Swift-XRT) have yielded ...
A. Kaur   +4 more
semanticscholar   +1 more source

Improved limits on Lorentz invariance violation from astrophysical gamma-ray sources [PDF]

open access: yesPhysical Review D, 2018
Lorentz invariance (LI) has a central role in science and its violation (LIV) at some high-energy scale has been related to possible solutions for several of the most intriguing puzzles in nature such as dark matter, dark energy, cosmic rays generation ...
R. Lang, H. Mart'inez-Huerta, V. Souza
semanticscholar   +1 more source

VERITAS and Fermi-LAT Observations of TeV Gamma-Ray Sources Discovered by HAWC in the 2HWC Catalog [PDF]

open access: yesAstrophysical Journal, 2018
The High Altitude Water Cherenkov (HAWC) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100 GeV) gamma-ray sources based on 507 days of observation. Among these, 19 sources are not associated with previously known
A. Abeysekara   +278 more
semanticscholar   +1 more source

Extending the event-weighted pulsation search to very faint gamma-ray sources [PDF]

open access: yesAstronomy & Astrophysics, 2018
Context. Because of the relatively broad angular resolution of current gamma-ray instruments in the MeV–GeV energy range, the photons of a given source are mixed with those coming from nearby sources or diffuse background. This source confusion seriously
P. Bruel
semanticscholar   +1 more source

An Indication of Anisotropy in Arrival Directions of Ultra-high-energy Cosmic Rays through Comparison to the Flux Pattern of Extragalactic Gamma-Ray Sources [PDF]

open access: yes, 2018
A new analysis of the data set from the Pierre Auger Observatory provides evidence for anisotropy in the arrival directions of ultra-high-energy cosmic rays on an intermediate angular scale, which is indicative of excess arrivals from strong, nearby ...
T. P. A. C. A. Aab   +391 more
semanticscholar   +1 more source

AGILE Detection of Gamma-Ray Sources Coincident with Cosmic Neutrino Events [PDF]

open access: yesAstrophysical Journal, 2018
The origin of cosmic neutrinos is still largely unknown. Using data obtained by the gamma-ray imager on board the Astro-rivelatore Gamma a Immagini Leggero (AGILE) satellite, we systematically searched for transient gamma-ray sources above 100 MeV that ...
F. Lucarelli   +41 more
semanticscholar   +1 more source

Home - About - Disclaimer - Privacy