On the synchrotron self-compton emission from relativistic shocks and its implications for gamma-ray burst afterglows

被引:427
作者
Sari, R [1 ]
Esin, AA [1 ]
机构
[1] 130 33 CALTECH, Pasadena, CA 91125 USA
关键词
gamma rays : bursts; radiation mechanisms : nonthermal;
D O I
10.1086/319003
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We consider the effects of inverse Compton scattering of synchrotron photons from relativistic electrons in gamma -ray burst (GRB) afterglows. We compute the spectrum of the inverse Compton emission and find that it can dominate the total cooling rate of the afterglow for several months or even years after the initial explosion. We demonstrate that the presence of strong inverse Compton cooling can be deduced from the effect it has on the time evolution of the cooling break in the synchrotron spectral component, and therefore on the optical and X-ray afterglow light curves. We then show how the physical interpretation of the observed characteristics of the synchrotron spectrum must be modified to take into consideration this extra source of cooling and give a revised prescription for computing physical parameters characterizing the expanding shock wave from the observed quantities. We find that for a given set of observables (synchrotron break frequencies and fluxes) there is either no consistent physical interpretation or two of them. Finally we discuss the prospects of directly detecting the inverse Compton emission with Chandra. We argue that such a detection is possible for GRBs exploding in a reasonably dense (n greater than or similar to 1 cm(-3)) medium.
引用
收藏
页码:787 / 799
页数:13
相关论文
共 23 条
[1]   RADIATION FROM RELATIVISTIC BLAST WAVES IN QUASARS AND ACTIVE GALACTIC NUCLEI [J].
BLANDFORD, RD ;
MCKEE, CF .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1977, 180 (02) :343-371
[2]   BREMSSTRAHLUNG, SYNCHROTRON RADIATION, AND COMPTON SCATTERING OF HIGH-ENERGY ELECTRONS TRAVERSING DILUTE GASES [J].
BLUMENTHAL, GR ;
GOULD, RJ .
REVIEWS OF MODERN PHYSICS, 1970, 42 (02) :237-+
[3]   Wind interaction models for gamma-ray burst afterglows: The case for two types of progenitors [J].
Chevalier, RA ;
Li, ZY .
ASTROPHYSICAL JOURNAL, 2000, 536 (01) :195-212
[4]   Synchrotron and synchrotron self-compton emission and the blast-wave model of gamma-ray bursts [J].
Chiang, J ;
Dermer, CD .
ASTROPHYSICAL JOURNAL, 1999, 512 (02) :699-710
[5]   Spectral energy distributions of gamma-ray bursts energized by external shocks [J].
Dermer, CD ;
Böttcher, M ;
Chiang, J .
ASTROPHYSICAL JOURNAL, 2000, 537 (01) :255-260
[6]   Beaming, baryon loading, and the synchrotron self-compton component in gamma-ray bursts [J].
Dermer, CD ;
Chiang, J ;
Mitman, KE .
ASTROPHYSICAL JOURNAL, 2000, 537 (02) :785-795
[7]  
FREEDMAN DL, 2001, IN PRESS APJ
[8]   Radio-to-X-ray spectrum of GRB 970508 on 1997 May 21.0 UT [J].
Galama, TJ ;
Wijers, RAMJ ;
Bremer, M ;
Groot, PJ ;
Strom, RG ;
Kouveliotou, C ;
van Paradijs, J .
ASTROPHYSICAL JOURNAL, 1998, 500 (02) :L97-L100
[9]   Synchrotron self-absorption in gamma-ray burst afterglow [J].
Granot, J ;
Piran, T ;
Sari, R .
ASTROPHYSICAL JOURNAL, 1999, 527 (01) :236-246
[10]   2 POPULATIONS AND MODELS OF GAMMA-RAY BURSTS [J].
KATZ, JI .
ASTROPHYSICAL JOURNAL, 1994, 422 (01) :248-259