LONG-DURATION X-RAY FLASH AND X-RAY-RICH GAMMA-RAY BURSTS FROM LOW-MASS POPULATION III STARS

AbstractThe properties of the Supernovae discovered in coincidence with long-duration Gamma-ray Bursts and X-Ray Flashes are reviewed, and compared to those of SNe for which GRBs are not observed. The SNe associated with GRBs are of Type Ic, they are brighter than the norm, and show very broad absorption lines in their spectra, indicative of high expansion velocities and hence of large explosion kinetic energies. This points to a massive star origin, and to the birth of a black hole at the time of core collapse. There is strong evidence for gross asymmetries in the SN ejecta. The observational evidence seems to suggest that GRB/SNe are more massive and energetic than XRF/SNe, and come from more massive stars. While for GRB/SNe the collapsar model is favoured, XRF/SNe may host magnetars.

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Gamma-ray bursts from massive Population-III stars: clues from the radio band

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stw905 ◽

2016 ◽

Vol 459 (3) ◽

pp. 3356-3362 ◽

Cited By ~ 1

Author(s):

D. Burlon ◽

T. Murphy ◽

G. Ghirlanda ◽

P. J. Hancock ◽

R. Parry ◽

...

Keyword(s):

Gamma Ray ◽

Gamma Ray Bursts ◽

Population Iii Stars ◽

Radio Band ◽

Population Iii

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On the Relation Between GRB Classes and X-ray Flashes

Acta Polytechnica ◽

10.14311/1496 ◽

2012 ◽

Vol 52 (1) ◽

Author(s):

Z. Bagoly ◽

P. Veres ◽

I. Horváth ◽

A. Mészáros ◽

L. G. Balázs

Keyword(s):

Physical Properties ◽

Short Duration ◽

Classification Scheme ◽

Gamma Ray ◽

Gamma Ray Bursts ◽

The Other ◽

X Ray ◽

Intermediate Group ◽

Long Duration

Gamma-ray bursts are usually classified into either short-duration or long-duration bursts. Going beyond the short-long classification scheme, it has been shown on statistical grounds that a third, intermediate population is needed in this classification scheme. We are looking for physical properties which discriminate the intermediate duration bursts from the other two classes. As the intermediate group is the softest, we argue that we have related them with X-ray flashes among the GRBs. We give a new, probabilistic definition for this class of events.

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Gamma-ray Bursts

International Astronomical Union Colloquium ◽

10.1017/s0252921100009544 ◽

2005 ◽

Vol 192 ◽

pp. 459-466

Author(s):

Alberto J. Castro-Tirado

Keyword(s):

Gamma Ray ◽

Massive Stars ◽

Gamma Ray Bursts ◽

Compact Objects ◽

X Ray ◽

Long Duration ◽

Multi Wavelength ◽

New Generation ◽

Short Grbs

SummarySince their discovery in 1967 Gamma-ray bursts (GRBs) have been puzzling to astrophysicists. With the advent of a new generation of X–ray satellites in the late 90’s, it was possible to carry out deep multi-wavelength observations of the counterparts associated with the long duration GRBs class just within a few hours of occurrence, thanks to the observation of the fading X-ray emission that follows the more energetic gamma-ray photons once the GRB event has ended. The fact that this emission (the afterglow) extends at longer wavelengths, led to the discovery of optical/IR/radio counterparts in 1997-2003, greatly improving our understanding of these sources. The classical, long duration GRBs, have been observed to originate at cosmological distances in a range of redshifts with 0.1685 ≤ z ≤ 4.50 implying energy releases of ~ 1051 ergs. The recent results on GRB 021004 and GRB 030329 confirm that the central engines that power these extraordinary events are due to be collapse of massive stars rather than the merging of compact objects as previously also suggested. Short GRBs still remain a mystery as no counterparts have been detected so far.

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Can we quickly flag ultra-long gamma-ray bursts?

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1036 ◽

2019 ◽

Vol 486 (2) ◽

pp. 2471-2476 ◽

Cited By ~ 4

Author(s):

B Gendre ◽

Q T Joyce ◽

N B Orange ◽

G Stratta ◽

J L Atteia ◽

...

Keyword(s):

Gamma Ray ◽

High Energy ◽

Gamma Ray Bursts ◽

Wide Field ◽

Exact Nature ◽

X Ray ◽

Central Engine ◽

Long Duration ◽

Limited Coverage

Abstract Ultra-long gamma-ray bursts are a class of high-energy transients lasting several hours. Their exact nature is still elusive, and several models have been proposed to explain them. Because of the limited coverage of wide-field gamma-ray detectors, the study of their prompt phase with sensitive narrow-field X-ray instruments could help in understanding the origin of ultra-long GRBs. However, the observers face a true problem in rapidly activating follow-up observations, due to the challenging identification of an ultra-long GRB before the end of the prompt phase. We present here a comparison of the prompt properties available after a few tens of minutes of a sample of ultra-long GRBs and normal long GRBs, looking for prior indicators of the long duration. We find that there is no such clear prior indicator of the duration of the burst. We also found that statistically, a burst lasting at least 10 and 20 minutes has respectively $28{{\ \rm per\ cent}}$ and $50{{\ \rm per\ cent}}$ probability to be an ultralong event. These findings point towards a common central engine for normal long and ultra-long GRBs, with the collapsar model privileged.

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Low-mass x-ray binaries and gamma-ray bursts

10.1063/1.42831 ◽

1991 ◽

Author(s):

J. P. Lasota ◽

J. Frank ◽

A. R. King

Keyword(s):

Gamma Ray ◽

Gamma Ray Bursts ◽

X Ray ◽

Low Mass ◽

X Ray Binaries

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Precessing magnetars as central engines in short gamma-ray bursts

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab153 ◽

2021 ◽

Vol 502 (2) ◽

pp. 2482-2494

Author(s):

A G Suvorov ◽

K D Kokkotas

Keyword(s):

Gamma Ray ◽

Magnetic Energy ◽

Information Criterion ◽

Gamma Ray Bursts ◽

Internal Stresses ◽

X Ray ◽

Compact Binary ◽

Long Duration ◽

Hydrodynamic Evolution ◽

Data Points

ABSTRACT Short gamma-ray bursts that are followed by long-duration X-ray plateaus may be powered by the birth, and hydrodynamic evolution, of magnetars from compact binary coalescence events. If the rotation and magnetic axes of the system are not orthogonal to each other, the star will undergo free precession, leading to fluctuations in the luminosity of the source. In some cases, precession-induced modulations in the spin-down power may be discernible in the X-ray flux of the plateau. In this work, 25 X-ray light curves associated with bursts exhibiting a plateau are fitted to luminosity profiles appropriate for precessing, oblique rotators. Based on the Akaike Information Criterion, 16 $(64{{\ \rm per\ cent}})$ of the magnetars within the sample display either moderate or strong evidence for precession. Additionally, since the precession period of the star is directly tied to its quadrupolar ellipticity, the fits allow for an independent measure of the extent to which the star is deformed by internal stresses. Assuming these deformations arise due to a mixed poloidal–toroidal magnetic field, we find that the distribution of magnetic-energy ratios is bimodal, with data points clustering around energetically equal and toroidally dominated partitions. Implications of this result for gravitational-wave emission and dynamo activity in newborn magnetars are discussed.

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