排序方式: 共有4条查询结果,搜索用时 15 毫秒
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Burrows DN Kennea JA Ghisellini G Mangano V Zhang B Page KL Eracleous M Romano P Sakamoto T Falcone AD Osborne JP Campana S Beardmore AP Breeveld AA Chester MM Corbet R Covino S Cummings JR D'Avanzo P D'Elia V Esposito P Evans PA Fugazza D Gelbord JM Hiroi K Holland ST Huang KY Im M Israel G Jeon Y Jeon YB Jun HD Kawai N Kim JH Krimm HA Marshall FE P Mészáros Negoro H Omodei N Park WK Perkins JS Sugizaki M Sung HI Tagliaferri G Troja E Ueda Y Urata Y Usui R Antonelli LA Barthelmy SD Cusumano G 《Nature》2011,476(7361):421-424
Supermassive black holes have powerful gravitational fields with strong gradients that can destroy stars that get too close, producing a bright flare in ultraviolet and X-ray spectral regions from stellar debris that forms an accretion disk around the black hole. The aftermath of this process may have been seen several times over the past two decades in the form of sparsely sampled, slowly fading emission from distant galaxies, but the onset of the stellar disruption event has not hitherto been observed. Here we report observations of a bright X-ray flare from the extragalactic transient Swift J164449.3+573451. This source increased in brightness in the X-ray band by a factor of at least 10,000 since 1990 and by a factor of at least 100 since early 2010. We conclude that we have captured the onset of relativistic jet activity from a supermassive black hole. A companion paper comes to similar conclusions on the basis of radio observations. This event is probably due to the tidal disruption of a star falling into a supermassive black hole, but the detailed behaviour differs from current theoretical models of such events. 相似文献
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Thöne CC de Ugarte Postigo A Fryer CL Page KL Gorosabel J Aloy MA Perley DA Kouveliotou C Janka HT Mimica P Racusin JL Krimm H Cummings J Oates SR Holland ST Siegel MH De Pasquale M Sonbas E Im M Park WK Kann DA Guziy S García LH Llorente A Bundy K Choi C Jeong H Korhonen H Kubànek P Lim J Moskvitin A Muñoz-Darias T Pak S Parrish I 《Nature》2011,480(7375):72-74
Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae. They release ultra-relativistic jets, which produce non-thermal emission through synchrotron radiation as they interact with the surrounding medium. Here we report observations of the unusual GRB 101225A. Its γ-ray emission was exceptionally long-lived and was followed by a bright X-ray transient with a hot thermal component and an unusual optical counterpart. During the first 10 days, the optical emission evolved as an expanding, cooling black body, after which an additional component, consistent with a faint supernova, emerged. We estimate its redshift to be z = 0.33 by fitting the spectral-energy distribution and light curve of the optical emission with a GRB-supernova template. Deep optical observations may have revealed a faint, unresolved host galaxy. Our proposed progenitor is a merger of a helium star with a neutron star that underwent a common envelope phase, expelling its hydrogen envelope. The resulting explosion created a GRB-like jet which became thermalized by interacting with the dense, previously ejected material, thus creating the observed black body, until finally the emission from the supernova dominated. An alternative explanation is a minor body falling onto a neutron star in the Galaxy. 相似文献
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Racusin JL Karpov SV Sokolowski M Granot J Wu XF Pal'shin V Covino S van der Horst AJ Oates SR Schady P Smith RJ Cummings J Starling RL Piotrowski LW Zhang B Evans PA Holland ST Malek K Page MT Vetere L Margutti R Guidorzi C Kamble AP Curran PA Beardmore A Kouveliotou C Mankiewicz L Melandri A O'Brien PT Page KL Piran T Tanvir NR Wrochna G Aptekar RL Barthelmy S Bartolini C Beskin GM Bondar S Bremer M Campana S Castro-Tirado A Cucchiara A Cwiok M D'Avanzo P D'Elia V Valle MD de Ugarte Postigo A 《Nature》2008,455(7210):183-188
Long-duration gamma-ray bursts (GRBs) release copious amounts of energy across the entire electromagnetic spectrum, and so provide a window into the process of black hole formation from the collapse of massive stars. Previous early optical observations of even the most exceptional GRBs (990123 and 030329) lacked both the temporal resolution to probe the optical flash in detail and the accuracy needed to trace the transition from the prompt emission within the outflow to external shocks caused by interaction with the progenitor environment. Here we report observations of the extraordinarily bright prompt optical and gamma-ray emission of GRB 080319B that provide diagnostics within seconds of its formation, followed by broadband observations of the afterglow decay that continued for weeks. We show that the prompt emission stems from a single physical region, implying an extremely relativistic outflow that propagates within the narrow inner core of a two-component jet. 相似文献
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Soderberg AM Berger E Page KL Schady P Parrent J Pooley D Wang XY Ofek EO Cucchiara A Rau A Waxman E Simon JD Bock DC Milne PA Page MJ Barentine JC Barthelmy SD Beardmore AP Bietenholz MF Brown P Burrows A Burrows DN Bryngelson G Byrngelson G Cenko SB Chandra P Cummings JR Fox DB Gal-Yam A Gehrels N Immler S Kasliwal M Kong AK Krimm HA Kulkarni SR Maccarone TJ Mészáros P Nakar E O'Brien PT Overzier RA de Pasquale M Racusin J Rea N York DG 《Nature》2008,453(7194):469-474
Massive stars end their short lives in spectacular explosions--supernovae--that synthesize new elements and drive galaxy evolution. Historically, supernovae were discovered mainly through their 'delayed' optical light (some days after the burst of neutrinos that marks the actual event), preventing observations in the first moments following the explosion. As a result, the progenitors of some supernovae and the events leading up to their violent demise remain intensely debated. Here we report the serendipitous discovery of a supernova at the time of the explosion, marked by an extremely luminous X-ray outburst. We attribute the outburst to the 'break-out' of the supernova shock wave from the progenitor star, and show that the inferred rate of such events agrees with that of all core-collapse supernovae. We predict that future wide-field X-ray surveys will catch each year hundreds of supernovae in the act of exploding. 相似文献
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