The Bright Optical Flash and Afterglow from the Gamma-Ray Burst GRB 130427A

The optical light generated simultaneously with x-rays and gamma rays during a gamma-ray burst (GRB) provides clues about the nature of the explosions that occur as massive stars collapse. We report on the bright optical flash and fading afterglow from powerful burst GRB 130427A. The optical and >100–megaelectron volt (MeV) gamma-ray flux show a close correlation during the first 7000 seconds, which is best explained by reverse shock emission cogenerated in the relativistic burst ejecta as it collides with surrounding material. At later times, optical observations show the emergence of emission generated by a forward shock traversing the circumburst environment. The link between optical afterglow and >100-MeV emission suggests that nearby early peaked afterglows will be the best candidates for studying gamma-ray emission at energies ranging from gigaelectron volts to teraelectron volts.

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Physical Constraints on Models of Gamma-Ray Bursters

International Astronomical Union Colloquium ◽

10.1017/s0252921100086140 ◽

1986 ◽

Vol 89 ◽

pp. 305-321

Author(s):

Richard I. Epstein

Keyword(s):

Gamma Rays ◽

Gamma Ray ◽

High Energy ◽

X Rays ◽

Burst Source ◽

Gamma Ray Burst ◽

Physical Constraints ◽

Low Energies ◽

Energy Gamma ◽

Photon Interactions

AbstractThe power per logarithmic bandwidth in gamma-ray burst spectra generally increases rapidly with energy through the x-ray range and does not cut off sharply above a few MeV. This spectral form indicates that a very small fraction of the energy from a gamma-ray burst source is emitted at low energies or is reprocessed into x-rays and that the high-energy gamma rays are not destroyed by photon-photon interactions. The implications are that the emission mechanism for the gamma-ray bursts is not synchrotron radiation from electrons that lose most of their energy before being re-accelerated and that either the regions from which the gamma rays are emitted are large compared to the size of a neutron star or the emission is collimated and beamed away from the stellar surface.

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The Flare of 1989 September 9, 09:09 UT: Does Coronal Loop Collision Initiate Efficient Gamma-Ray Emission?

International Astronomical Union Colloquium ◽

10.1017/s0252921100078003 ◽

1994 ◽

Vol 142 ◽

pp. 707-711

Author(s):

H. Aurass ◽

A. Hofmann ◽

E. Rieger

Keyword(s):

Current Sheet ◽

Gamma Rays ◽

Coronal Loop ◽

Gamma Ray ◽

High Energy ◽

X Rays ◽

Subject Headings ◽

Γ Ray ◽

Gamma Ray Emission ◽

Magnetogram Data

AbstractVector magnetogram data and Hα pictures together with data published by Chupp et al. lead us to conjecture that in the presented case a contact between the rising two-ribbon flare current sheet and a coronal loop connecting two nearby plage regions initiates efficient high-energy γ-ray emission.Subject headings: Sun: corona — Sun: flares — Sun: X-rays, gamma rays

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Gamma-ray burst afterglow blast waves

International Journal of Modern Physics D ◽

10.1142/s0218271818420026 ◽

2018 ◽

Vol 27 (13) ◽

pp. 1842002 ◽

Cited By ~ 8

Author(s):

Hendrik van Eerten

Keyword(s):

Gamma Ray ◽

Blast Waves ◽

Dense Medium ◽

X Rays ◽

Reverse Shock ◽

Stellar Envelope ◽

Gamma Ray Burst ◽

Shock System ◽

Set Up ◽

The Universe

The various stages of baryonic gamma-ray burst (GRB) afterglow blast waves are reviewed. These are responsible for the afterglow emission from which much of our understanding of gamma-ray bursts derives. Initially, the blast waves are confined to the dense medium surrounding the burster (stellar envelope or dense wind), giving rise to a jet-cocoon structure. A massive ejecta is released and potentially fed by ongoing energy release from the burster and a forward–reverse shock system is set up between ejecta and ambient density. Ultimately the blast wave spreads sideways and slows down, and the dominant afterglow emission shifts from X-rays down to radio. Over the past years significant progress has been made both observationally and theoretically/numerically in our understanding of these blast waves, unique in the universe due to their often incredibly high initial Lorentz factors of 100–1000. The recent discovery of a short gamma-ray burst counterpart to a gravitational wave detection (GW 170817) brings the promise of a completely new avenue to explore and constrain the dynamics of gamma-ray burst blast waves.

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A REVIEW OF PARTICLE-INDUCED X-RAY EMISSION IN GEOLOGY

International Journal of PIXE ◽

10.1142/s0129083591000226 ◽

1991 ◽

Vol 01 (04) ◽

pp. 311-338 ◽

Cited By ~ 13

Author(s):

J. D. MACARTHUR ◽

XIN-PEI MA

Keyword(s):

Gamma Rays ◽

Gamma Ray ◽

Light Element ◽

X Rays ◽

Geological Samples ◽

Geological Material ◽

Element Analysis ◽

X Ray ◽

Gamma Ray Emission

Particle-induced X-ray emission is very well suited for the analysis of geological samples. This review discusses the characteristics for such analyses. For light-element analysis, the complimentary technique of particle-induced gamma ray emission is also discussed since the emission of gamma rays occurs simultaneously with the X-rays. Not only are exploratory investigations of PIXE's capabilities presented but also synopses of studies aimed at answering geological questions. The latter have become more and more common in the last few years, an indication of PIXE's maturity as a technique for clement analysis of geological material.

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Radio jets and gamma-ray emission in radio-silent narrow-line Seyfert 1 galaxies

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833378 ◽

2018 ◽

Vol 614 ◽

pp. L1 ◽

Cited By ~ 20

Author(s):

A. Lähteenmäki ◽

E. Järvelä ◽

V. Ramakrishnan ◽

M. Tornikoski ◽

J. Tammi ◽

...

Keyword(s):

Gamma Rays ◽

Supernova Remnants ◽

Gamma Ray ◽

Spiral Galaxies ◽

Narrow Line ◽

Radio Jets ◽

Relativistic Jet ◽

Gamma Ray Emission

We have detected six narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz that were previously classified as radio silent and two that were classified as radio quiet. These detections reveal the presumption that NLS1 galaxies labelled radio quiet or radio silent and hosted by spiral galaxies are unable to launch jets to be incorrect. The detections are a plausible indicator of the presence of a powerful, most likely relativistic jet because this intensity of emission at 37 GHz cannot be explained by, for example, radiation from supernova remnants. Additionally, one of the detected NLS1 galaxies is a newly discovered source of gamma rays and three others are candidates for future detections.

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X-ray and optical observations of the November 19, 1978 Gamma-Ray Burst source region

Space Science Reviews ◽

10.1007/bf01246066 ◽

1981 ◽

Vol 30 (1-4) ◽

pp. 467-470 ◽

Cited By ~ 10

Author(s):

G. Pizzichini ◽

J. Danziger ◽

P. Grosb� ◽

M. Tarenghi ◽

T. L. Cline ◽

...

Keyword(s):

Gamma Ray ◽

Source Region ◽

Optical Observations ◽

Burst Source ◽

Gamma Ray Burst ◽

X Ray

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Diverse Features of the Multiwavelength Afterglows of Gamma-Ray Bursts: Natural or Special?

Advances in Astronomy ◽

10.1155/2016/1592148 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

J. J. Geng ◽

Y. F. Huang

Keyword(s):

Black Holes ◽

Numerical Method ◽

Gamma Ray ◽

Gamma Ray Bursts ◽

Shock Model ◽

Reverse Shock ◽

X Ray ◽

Electron Positron ◽

Forward Shock ◽

Electron Positron Pair

The detection of optical rebrightenings and X-ray plateaus in the afterglows of gamma-ray bursts (GRBs) challenges the generic external shock model. Recently, we have developed a numerical method to calculate the dynamics of the system consisting of a forward shock and a reverse shock. Here, we briefly review the applications of this method in the afterglow theory. By relating these diverse features to the central engines of GRBs, we find that the steep optical rebrightenings would be caused by the fall-back accretion of black holes, while the shallow optical rebrightenings are the consequence of the injection of the electron-positron-pair wind from the central magnetar. These studies provide useful ways to probe the characteristics of GRB central engines.

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