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Related papers: Flares in Gamma Ray Bursts (II)

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Gamma-ray bursts (GRBs) are the most energetic phenomena in the Universe, characterized by prompt gamma-ray emission followed by multiwavelength afterglows. X-ray flares, observed during the afterglow phase, are generally believed to…

High Energy Astrophysical Phenomena · Physics 2025-10-22 Yinuo Ma , He Gao

The study of the early high-energy emission from both long and short Gamma-ray bursts has been revolutionized by the Swift mission. The rapid response of Swift shows that the non-thermal X-ray emission transitions smoothly from the prompt…

Astrophysics · Physics 2009-11-11 P. T. O'Brien , R. Willingale , J. P. Osborne , M. R. Goad

We analyze optical and X-ray observations of GRB 050904 obtained with TAROT and SWIFT. We perform temporal and spectral analysis of the X-ray and optical data. We find significant absorption in the early phase of the X-ray light curve, with…

Astrophysics · Physics 2012-08-27 B. Gendre , A. Galli , A. Corsi , A. Klotz , L. Piro , G. Stratta , M. Boer , Y. Damerdji

The flat decay phase in the first 1e2-1e4 seconds of the X-ray light curve of Gamma Ray Bursts (GRBs) has not yet found a convincing explanation. The fact that the optical and X-ray lightcurves are often different, with breaks at different…

Astrophysics · Physics 2009-11-13 G. Ghisellini , G. Ghirlanda , L. Nava , C. Firmani

Prompt or early optical emission in gamma-ray bursts is notoriously difficult to measure, and observations of the dozen cases show a large variety of properties. Yet, such early emission promises to help us achieve a better understanding of…

In this paper we shed light on late time (i.e. with peak time t_{pk} \gtrsim 1000 s) flaring activity. We address the morphology and energetic of flares in the window \sim 10^3-10^6 s to put constraints on the temporal evolution of the…

High Energy Astrophysical Phenomena · Physics 2015-05-18 M. G. Bernardini , R. Margutti , G. Chincarini , C. Guidorzi , J. Mao

BAT and XRT observations of two recent well-covered GRBs observed by Swift, GRB 050315 and GRB 050319, show clearly a prompt component joining the onset of the afterglow emission. By fitting a power law form to the gamma-ray spectrum, we…

Well-sampled optical lightcurves of 146 gamma-ray bursts (GRBs) are compiled from the literature. By empirical fitting we identify eight possible emission components and summarize the results in a "synthetic" lightcurve. Both optical flare…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Liang Li , En-Wei Liang , Qing-Wen Tang , Jie-Min Chen , Shao-Qiang Xi , Hou-Jun LV , He Gao , Bing Zhang , Jin Zhang , Shuang-Xi Yi , Rui-Jing Lu , Lian-Zhong LV , Jian-Yan Wei

We present the first systematic investigation of the morphological and timing properties of flares in GRBs observed by Swift/XRT. We consider a large sample drawn from all GRBs detected by Swift, INTEGRAL and HETE-2 prior to 2006 Jan 31,…

Understanding the origin and diversity of emission processes responsible for Gamma-ray Bursts (GRBs) remains a pressing challenge. While prompt and contemporaneous panchromatic observations have the potential to test predictions of the…

We present the results of X-ray and optical observations of GRB050712 performed by Swift. The X-ray lightcurve of this burst exhibits episodes of flares in the first 1000s, the same epoch at which the UVOT detected an optical counterpart. A…

As indicated by the observed X-ray flares, a great amount of energy could be intermediately released from the postburst central engine of gamma-ray bursts (GRBs). As a natural consequence, the GRB external shock could be energized over and…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Liang-Duan Liu , A-Ming Chen

Several GRB afterglow light curves deviate strongly from the power law decay observed in most bursts. We show that these variations can be accounted for by including refreshed shocks in the standard fireball model previously used to…

Astrophysics · Physics 2009-11-10 G. Bjornsson , E. H. Gudmundsson , G. Johannesson

The X-ray light curves of many gamma-ray bursts (GRBs) observed by the Swift X-Ray Telescope (XRT) have a very steep-decay component (tail) following the prompt gamma-rays in the early phase and have some erratic flares occurring at a time…

We discuss some of the preliminary results and findings derived from the analysis of a first sample of flares detected by the XRT on board Swift. The analysis shows that the morphology of flares is the one we expect from the collision of…

Swift discovered GRB 050713A and slewed promptly to begin observing with its narrow field instruments 72.6 seconds after the burst onset, while the prompt gamma-ray emission was still detectable in the BAT. Simultaneous emission from two…

The prompt emission of Gamma Ray Bursts extends from the early pulses observed in gamma-rays (>15 keV) to very late flares of X-ray photons (0.3-10 keV). The duration of prompt gamma-ray pulses is rather constant while the width of X-ray…

High Energy Astrophysical Phenomena · Physics 2018-08-01 A. Pescalli , M. Ronchi , G. Ghirlanda , G. Ghisellini

Until recently, X-ray flares during the afterglow of gamma ray bursts (GRBs) were a rarely detected phenomenon, thus their nature is unclear. During the afterglow of GRB 050502B, the largest X-ray flare ever recorded rose rapidly above the…

We present observations of the early X-ray emission for a sample of 40 gamma-ray bursts (GRBs) obtained using the Swift satellite for which the narrow-field instruments were pointed at the burst within 10 minutes of the trigger. Using data…

Flares are usually observed during the afterglow phase of Gamma-Ray Bursts (GRBs) in soft X-ray, optical and radio bands, but rarely in gamma-ray band. Despite the extraordinary brightness, GECAM-C has accurately measured both the bright…