Analysis of temporal features of gamma-ray bursts in the internal shock model

被引:60
作者
Spada, M [1 ]
Panaitescu, A
Mészáros, P
机构
[1] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA
[2] Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA
[3] Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy
关键词
gamma rays : bursts; methods : numerical; radiation mechanisms : nonthermal;
D O I
10.1086/309048
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
In a recent paper we calculated the power density spectrum of gamma-ray bursts arising from multiple shocks in a relativistic Rind. The wind optical thickness is one of the factors to which the power spectrum is most sensitive; therefore, we have further developed our model by taking into account the photon downscattering on the cold electrons in the wind. For an almost optically thick wind we identify a combination of ejection features and wind parameters that yield bursts with an average power spectrum in agreement with observations and with an efficiency of converting the wind kinetic energy in 50-300 keV emission of order 1%. For the same set of model features, the interval time between peaks and the pulse fluence have distributions consistent with the lognormal distribution observed in real bursts.
引用
收藏
页码:824 / 832
页数:9
相关论文
共 22 条
[1]  
Bagot P, 1998, ASTRON ASTROPHYS, V332, pL57
[2]   Self-similar temporal behavior of gamma-ray bursts [J].
Beloborodov, AM ;
Stern, BE ;
Svensson, R .
ASTROPHYSICAL JOURNAL, 1998, 508 (01) :L25-L27
[3]   Gamma-ray bursts from internal shocks in a relativistic wind: temporal and spectral properties [J].
Daigne, F ;
Mochkovitch, R .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1998, 296 (02) :275-286
[4]   GAMMA-RAY BURSTS [J].
FISHMAN, GJ ;
MEEGAN, CA .
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, 1995, 33 :415-458
[5]   Quasi-thermal comptonization and gamma-ray bursts [J].
Ghisellini, G ;
Celotti, A .
ASTROPHYSICAL JOURNAL, 1999, 511 (02) :L93-L96
[6]   The faint-galaxy hosts of gamma-ray bursts [J].
Hogg, DW ;
Fruchter, AS .
ASTROPHYSICAL JOURNAL, 1999, 520 (01) :54-58
[7]   Can internal shocks produce the variability in gamma-ray bursts? [J].
Kobayashi, S ;
Piran, T ;
Sari, R .
ASTROPHYSICAL JOURNAL, 1997, 490 (01) :92-98
[8]   Gamma-ray bursts and the cosmic star formation rate [J].
Krumholz, M ;
Thorsett, SE ;
Harrison, FA .
ASTROPHYSICAL JOURNAL, 1998, 506 (02) :L81-L84
[9]   Gamma-ray burst energetics [J].
Kumar, P .
ASTROPHYSICAL JOURNAL, 1999, 523 (02) :L113-L116
[10]   Log-normal distributions in gamma-ray burst time histories [J].
Li, H ;
Fenimore, EE .
ASTROPHYSICAL JOURNAL, 1996, 469 (02) :L115-L118