Results 81 to 90 of about 596,755 (352)

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

The 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

The afterglows of gamma-ray bursts [PDF]

AIP Conference Proceedings, 2000
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at cosmological distances with estimated electromagnetic energy release of 10**51 -- 10**53 erg, making these the brightest explosions in the Universe.
Kulkarni, S. R., Berger, E., Bloom, J. S., Chaffee, F., Diercks, A., Djorgovski, S. G., Frail, D. A., Galama, T. J., Goodrich, R. W., Harrison, F. A., Sari, R., Yost, S. A.   +11 more
openaire   +10 more sources

Swift Pointing and Gravitational-Wave Bursts from Gamma-Ray Burst Events

, 2003
The currently accepted model for gamma-ray burst phenomena involves the violent formation of a rapidly rotating solar-mass black hole. Gravitational waves should be associated with the black-hole formation, and their detection would permit this model to ...
Finn, Lee Samuel, Krishnan, Badri, Sutton, Patrick J.   +2 more
core   +1 more source

The Gamma Ray Pulsar Population [PDF]

, 1999
We apply a likelihood analysis to pulsar detections, pulsar upper limits, and diffuse background measurements from the OSSE and EGRET instruments on the Compton Gamma Ray Observatory to constrain the luminosity law for gamma-ray pulsars and some ...
Becker W., J. M. Cordes, Lyne A. G., Lyne A. G., M. A. McLaughlin, Mattox J. R., Nolan P. L.   +6 more
core   +2 more sources

Influence of Heat Treatment on Microstructure and Mechanical Properties at Elevated Temperatures of Nonweldable Ni‐Based Alloy Printed by Fused Filament Fabrication

Advanced Engineering Materials, EarlyView.
The fused filament‐fabricated MAR‐M247 alloy without hot isostatic pressing shows the lowest porosity of 4%. Heat treatment at 1220 °C produces coarse precipitates and carbides. Specimens heat‐treated at 1220 °C exhibit higher tensile strength (683 MPa) and elongation (10%) at room temperature.
Haneen Daoud, Ying Zheng, Agata Kulig, Natalja Agarkov, Esma Mese, Wolfgang Hofmann, Peter Würtele, Uwe Glatzel   +7 more
wiley   +1 more source

On the Deformation Behavior of Metastable CrMnNi Steels Processed by Directed Energy Deposition in Different Temperature Regimes

Advanced Engineering Materials, EarlyView.
In the present study, metastable CrMnNi steels with varying chemical compositions and a concomitantly altered stacking fault energy are processed via directed energy deposition and afterwards tested via tensile tests at different temperatures. The present study shows the influence of the manufacturing process on the elemental deformation mechanisms for
Julia Richter, Thomas Wegener, Florian Stredak, Gert Bartzsch, Steffen Scherbring, Javad Mola, Olena Volkova, Stefan Böhm, Thomas Niendorf   +8 more
wiley   +1 more source

Naked Forward Shock Seen in the TeV Afterglow Data of GRB 221009A

The Astrophysical Journal
We explore the implications of the light curve of the early TeV gamma-ray afterglow of GRB 221009A reported by the LHAASO Collaboration. We show that the reported offset of the reference time, T _* , allows the determination of the activation time of the
Dmitry Khangulyan, Felix Aharonian, Andrew M. Taylor   +2 more
doaj   +1 more source

Origin of the Gamma Rays* [PDF]

Nature, 1932
IT has long been known that some of the radio-elements emit a penetrating type of X-rays known as the gamma rays. It is clear that these radiations arising from the nucleus of the radioactive atom represent in a sense some of the characteristic modes of vibration of the nuclear structure. The wave-length and quantum energy of many of the stronger lines
openaire   +2 more sources

Cosmic-Ray Events as Background in Imaging Atmospheric Cherenkov Telescopes

, 2007
The dominant background for observations of gamma-rays in the energy region above 50 GeV with Imaging Atmospheric Cherenkov telescopes are cosmic-ray events.
Aharonian, Aharonian, Aharonian, Bass, Bleicher, G. Maier, Heck, Hillas, Hofmann, J. Knapp, Kalmykov, Knapp, Krawczynski, Schatz, Weekes   +14 more
core   +1 more source

Impact of Hot Isostatic Pressing on Microstructure Evolution and Creep Performance of Powder Bed Fusion–Laser Beam Processed CM247LC

Advanced Engineering Materials, EarlyView.
The influence of Hot Isostatic Pressing (HIP) temperature on the microstructure and creep performance of powder bed fusion–laser beam processed CM247LC superalloy is investigated. Grain growth and γ’ precipitate evolution are characterized following HIP at varying temperatures.
Ahmed Fardan, Johannes Gårdstam, Eva Oscarsson, Håkan Brodin, Eduard Hryha   +4 more
wiley   +1 more source