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Archive for History of Exact Sciences - Earlier than the Arabic-Latin transfer of Ptolemaic astronomy via the Iberian peninsula, a serious occupation with Arabic astronomy by Latin scholars took... 相似文献
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Gehrels N Sarazin CL O'Brien PT Zhang B Barbier L Barthelmy SD Blustin A Burrows DN Cannizzo J Cummings JR Goad M Holland ST Hurkett CP Kennea JA Levan A Markwardt CB Mason KO Meszaros P Page M Palmer DM Rol E Sakamoto T Willingale R Angelini L Beardmore A Boyd PT Breeveld A Campana S Chester MM Chincarini G Cominsky LR Cusumano G de Pasquale M Fenimore EE Giommi P Gronwall C Grupe D Hill JE Hinshaw D Hjorth J Hullinger D Hurley KC Klose S Kobayashi S Kouveliotou C Krimm HA Mangano V 《Nature》2005,437(7060):851-854
Gamma-ray bursts (GRBs) come in two classes: long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift (z approximately 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars. In contrast, no short GRB had been accurately (< 10') and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from--and the localization of--the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs. 相似文献
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Barthelmy SD Chincarini G Burrows DN Gehrels N Covino S Moretti A Romano P O'Brien PT Sarazin CL Kouveliotou C Goad M Vaughan S Tagliaferri G Zhang B Antonelli LA Campana S Cummings JR D'Avanzo P Davies MB Giommi P Grupe D Kaneko Y Kennea JA King A Kobayashi S Melandri A Meszaros P Nousek JA Patel S Sakamoto T Wijers RA 《Nature》2005,438(7070):994-996
Two short (< 2 s) gamma-ray bursts (GRBs) have recently been localized and fading afterglow counterparts detected. The combination of these two results left unclear the nature of the host galaxies of the bursts, because one was a star-forming dwarf, while the other was probably an elliptical galaxy. Here we report the X-ray localization of a short burst (GRB 050724) with unusual gamma-ray and X-ray properties. The X-ray afterglow lies off the centre of an elliptical galaxy at a redshift of z = 0.258 (ref. 5), coincident with the position determined by ground-based optical and radio observations. The low level of star formation typical for elliptical galaxies makes it unlikely that the burst originated in a supernova explosion. A supernova origin was also ruled out for GRB 050709 (refs 3, 31), even though that burst took place in a galaxy with current star formation. The isotropic energy for the short bursts is 2-3 orders of magnitude lower than that for the long bursts. Our results therefore suggest that an alternative source of bursts--the coalescence of binary systems of neutron stars or a neutron star-black hole pair--are the progenitors of short bursts. 相似文献
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