Gamma-ray bursts

Mészáros, P.

doi:10.1088/0034-4885/69/8/r01

Cited by 1,135 publications

(1,169 citation statements)

References 491 publications

(1,078 reference statements)

Supporting

Mentioning

1,137

Contrasting

Unclassified

Order By: Relevance

“…Additionally, high-redshift GRBs have been speculated to possibly differ from lower redshift events in their energy scales, durations, and circumburst media (Fryer et al 2001;Bromm et al 2003;Heger et al 2003;Suwa & Ioka 2011;Toma et al 2011). Due to time dilation, high-redshift GRBs also afford an opportunity to capture rapidly evolving reverse shock emission, and thereby a means of probing the Lorentz factor and composition of the relativistic ejecta powering the afterglow (Piran 2005;Mészáros 2006;Laskar et al 2013Laskar et al , 2014Laskar et al , 2016Perley et al 2014;Alexander et al 2017).…”

Section: Introductionmentioning

confidence: 99%

A VLA Study of High-redshift GRBs. I. Multiwavelength Observations and Modeling of GRB 140311A

Laskar

Berger

Chornock

et al. 2018

ApJ

View full text Add to dashboard Cite

We present the first results from a recently concluded study of GRBs at z  5 with the Karl G. Jansky Very Large Array (VLA). Spanning 1 to 85.5 GHz and 7 epochs from 1.5 to 82.3 days, our observations of GRB140311A are the most detailed joint radio and millimeter observations of a GRB afterglow at z  5 to date. In conjunction with optical/near-IR and X-ray data, the observations can be understood in the framework of radiation from a single blast wave shock with energy »É 8.5 10 K,iso 53 erg expanding into a constant density environment with density, » n 8 0 -cm 3 . The X-ray and radio observations require a jet break at » t 0.6 jet days, yielding an opening angle of q »  4 jet and a beaming-corrected blast wave kinetic energy of »É 2.2 10 K 50 erg. The results from our radio follow-up and multiwavelength modeling lend credence to the hypothesis that detected high-redshift GRBs may be more tightly beamed than events at lower redshift. We do not find compelling evidence for reverse shock emission, which may be related to fast cooling driven by the moderately high circumburst density.

show abstract

Section: Introductionmentioning

confidence: 99%

A VLA Study of High-redshift GRBs. I. Multiwavelength Observations and Modeling of GRB 140311A

Laskar

Berger

Chornock

et al. 2018

ApJ

View full text Add to dashboard Cite

show abstract

“…Gamma-ray bursts (GRBs) are the most luminous sources in the universe, and yet, their emission mechanism(s) is still lacking a unique explanation; for reviews see Mészáros (2006), Pe'er (2015), and Kumar & Zhang (2015). Observations of rapid temporal variability and extremely high-energy photons require GRBs to have ultra-relativistic motion of their outflow plasma with Lorentz factors at least as high as a few hundred , implying that most of the energy of the burst is in kinetic form.…”

Section: Introductionmentioning

confidence: 99%

The Anatomy of a Long Gamma-Ray Burst: A Simple Classification Scheme for the Emission Mechanism(s)

Bégué

Burgess

2016

ApJ

View full text Add to dashboard Cite

Ultra-relativistic motion and efficient conversion of kinetic energy to radiation are required by gamma-ray burst (GRB) observations, yet they are difficult to simultaneously achieve. Three leading mechanisms have been proposed to explain the observed emission emanating from GRB outflows: radiation from either relativistic internal or external shocks, or thermal emission from a photosphere. Previous works were dedicated to independently treating these three mechanisms and arguing for a sole, unique origin of the prompt emission of GRBs. In contrast, herein, we first explain why all three models are valid mechanisms and that a contribution from each of them is expected in the prompt phase. Additionally, we show that a single parameter, the dimensionless entropy of the GRB outflow, determines which mechanism contributes the most to the emission. More specifically, internal shocks dominate for low values of the dimensionless entropy, external shocks for intermediate values, and finally, photospheric emission for large values. We present a unified framework for the emission mechanisms of GRBs with easily testable predictions for each process.

show abstract

“…Jetted outflows are associated with YSOs, e.g., Reipurth & Bally (2001), µQSOs, e.g., Mirabel & Rodríguez (1999), AGN, e.g., Urry & Padovani (1995); Ferrari (1998) ;Meier, Koide & Uchida (2001), neutron stars and PWNe, e.g., Crab nebula jet (Weisskopf et al 2000) and are thought responsible for the GRBs, e.g., Zhang & Mészáros (2004); Piran (2005); Mészáros (2006). Jets are subject to current driven instability (CDI) where jets are magnetically dominated, and when kinetically dominated subject to the KelvinHelmholtz instability (KHI) driven by velocity shear between the jet and the surrounding medium.…”

Section: Introductionmentioning

confidence: 99%

The stability of astrophysical jets

Hardee

2010

Proc. IAU

View full text Add to dashboard Cite

Abstract. Jets are produced by young stellar objects (YSOs), by black hole binary star system "microquasars" (µQSOs), by active galactic nuclei (AGN), are associated with neutron stars and pulsar wind nebulae (PWNe), and are thought responsible for the gamma-ray bursts (GRBs). An understanding of these outflows must include how they are launched and collimated into jets, and how they propagate to large distances. Jets be they Poynting flux and/or kinetic flux dominated are current driven (CD) and/or Kelvin-Helmholtz (KH) velocity shear driven unstable. Here I present some of the work that is leading to a better understanding of the properties required for the observed relative stability of astrophysical jets.

show abstract

Gamma-ray bursts

Cited by 1,135 publications

References 491 publications

A VLA Study of High-redshift GRBs. I. Multiwavelength Observations and Modeling of GRB 140311A

A VLA Study of High-redshift GRBs. I. Multiwavelength Observations and Modeling of GRB 140311A

The Anatomy of a Long Gamma-Ray Burst: A Simple Classification Scheme for the Emission Mechanism(s)

The stability of astrophysical jets

Contact Info

Product

Resources

About