A possible explanation for the radio afterglow of GRB 980519: the dense medium effect

被引:21
作者
Wang, XY [1 ]
Dai, ZG
Lu, T
机构
[1] Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China
[2] Chinese Acad Sci, Inst High Energy Phys, LCRHEA, Beijing 100039, Peoples R China
关键词
hydrodynamics; shock waves; gamma-rays : bursts;
D O I
10.1046/j.1365-8711.2000.03660.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
GRB 980519 is characterized by its rapidly declining optical and X-ray afterglows. Explanations of this behaviour include models invoking a dense medium environment, which makes the shock wave evolve quickly into the subrelativistic phase, a jet-like outflow, and a wind-shaped circumburst medium environment. Recently, Frail et al. found that the latter two cases are consistent with the radio afterglow of this burst. Here, by considering the transrelativistic shock hydrodynamics, we show that the dense medium model can also account for the radio light curve quite well. The potential virtue of the dense medium model for GRB 980519 is that it implies a smaller angular size of the afterglow, which is essential for interpreting the strong modulation of the radio light curve. Optical extinction arising from the dense medium is not important if the prompt optical-UV flash accompanying the gamma-ray emission can destroy dust by sublimation out to an appreciable distance. Comparisons with some other radio afterglows are also discussed.
引用
收藏
页码:170 / 174
页数:5
相关论文
共 39 条
[1]   Observation of contemporaneous optical radiation from a γ-ray burst [J].
Akerlof, C ;
Balsano, R ;
Barthelmy, S ;
Bloch, J ;
Butterworth, P ;
Casperson, D ;
Cline, T ;
Fletcher, S ;
Frontera, F ;
Gisler, G ;
Heise, J ;
Hills, J ;
Kehoe, R ;
Lee, B ;
Marshall, S ;
McKay, T ;
Miller, R ;
Piro, L ;
Priedhorsky, W ;
Szymanski, J ;
Wren, J .
NATURE, 1999, 398 (6726) :400-402
[2]  
BLANDFORD RD, 1976, PHYS FLUIDS, V19, P1130, DOI 10.1063/1.861619
[3]   The unusual afterglow of the γ-ray burst of 26 March 1998 as evidence for a supernova connection [J].
Bloom, JS ;
Kulkarni, SR ;
Djorgovski, SG ;
Eichelberger, AC ;
Côté, P ;
Blakeslee, JP ;
Odewahn, SC ;
Harrison, FA ;
Frail, DA ;
Filippenko, AV ;
Leonard, DC ;
Riess, AG ;
Spinrad, H ;
Stern, D ;
Bunker, R ;
Dey, A ;
Grossan, B ;
Perlmutter, S ;
Knop, RA ;
Hook, IM ;
Feroci, M .
NATURE, 1999, 401 (6752) :453-456
[4]   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
[5]   Gamma-ray burst environments and progenitors [J].
Chevalier, RA ;
Li, ZY .
ASTROPHYSICAL JOURNAL, 1999, 520 (01) :L29-L32
[6]   Gamma-ray burst afterglows: effects of radiative corrections and non-uniformity of the surrounding medium [J].
Dai, ZG ;
Lu, T .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1998, 298 (01) :87-92
[7]  
Dai ZG, 1999, ASTROPHYS J, V519, pL155, DOI 10.1086/312127
[8]   Gamma-ray burst afterglows from realistic fireballs [J].
Dai, ZG ;
Huang, YF ;
Lu, T .
ASTROPHYSICAL JOURNAL, 1999, 520 (02) :634-640
[9]  
DAI ZG, 1999, IN PRESS APJ, P537
[10]  
DJORGOVSKI SG, 1998, 79 GCN