A theory of photospheric emission from relativistic, collimated outflows

被引：148

作者：

Lundman, C. ^{[1
,2
]}

Pe'er, A. ^{[3
]}

Ryde, F. ^{[1
,2
]}

机构：

[1] AlbaNova, Dept Phys, Royal Inst Technol KTH, SE-10691 Stockholm, Sweden

[2] AlbaNova, Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden

[3] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2013年 / 428卷 / 03期

关键词：

plasmas; radiation mechanisms: thermal; radiative transfer; scattering; gamma-ray burst: general; GAMMA-RAY-BURSTS; SPECTRAL CATALOG; PEAK ENERGY; NONTHERMAL EMISSION; FERMI OBSERVATIONS; THERMAL EMISSION; JETS; COMPONENT; MODEL; COLLAPSARS;

D O I：

10.1093/mnras/sts219

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Relativistic outflows in the form of jets are common in many astrophysical objects. By their very nature, jets have angle-dependent velocity profiles, Gamma = Gamma(r,theta, phi), where Gamma is the outflow Lorentz factor. In this work we consider photospheric emission from non-dissipative jets with various Lorentz factor profiles, of the approximate form Gamma approximate to Gamma(0)/[(theta/theta(j))(p) + 1], where theta(j) is the characteristic jet opening angle. In collimated jets, the observed spectrum depends on the viewing angle, theta(v). We show that for narrow jets (theta(j)Gamma(0) less than or similar to few), the obtained low-energy photon index is alpha approximate to -1 (dN/dE alpha E-alpha), independent of viewing angle, and weakly dependent on the Lorentz factor gradient (p). A similar result is obtained for wider jets observed at theta(v) approximate to theta(j). This result is surprisingly similar to the average low-energy photon index seen in gamma-ray bursts. For wide jets (theta(j)Gamma(0) greater than or similar to few) observed at theta(v) << theta(j), a multicolour blackbody spectrum is obtained. We discuss the consequences of this theory on our understanding of the prompt emission in gamma-ray bursts.

引用

页码：2430 / 2442

页数：13

共 50 条

[1] FERMI OBSERVATIONS OF GRB 090902B: A DISTINCT SPECTRAL COMPONENT IN THE PROMPT AND DELAYED EMISSION [J].

Abdo, A. A. ;

Ackermann, M. ;

Ajello, M. ;

Asano, K. ;

Atwood, W. B. ;

Axelsson, M. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Baring, M. G. ;

Bastieri, D. ;

Bechtol, K. ;

Bellazzini, R. ;

Berenji, B. ;

Bhat, P. N. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bonamente, E. ;

Borgland, A. W. ;

Bouvier, A. ;

Bregeon, J. ;

Brez, A. ;

Briggs, M. S. ;

Brigida, M. ;

Bruel, P. ;

Burgess, J. M. ;

Burrows, D. N. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caraveo, P. A. ;

Casandjian, J. M. ;

Cecchi, C. ;

Celik, Oe. ;

Chekhtman, A. ;

Cheung, C. C. ;

Chiang, J. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Cominsky, L. R. ;

Connaughton, V. ;

Conrad, J. ;

Cutini, S. ;

d'Elia, V. ;

Dermer, C. D. ;

de Angelis, A. ;

de Palma, F. ;

Digel, S. W. .

ASTROPHYSICAL JOURNAL LETTERS, 2009, 706 (01) :L138-L144

[2] THE APPEARANCE OF HIGHLY RELATIVISTIC, SPHERICALLY SYMMETRICAL STELLAR WINDS [J].

ABRAMOWICZ, MA ;

NOVIKOV, ID ;

PACZYNSKI, B .

ASTROPHYSICAL JOURNAL, 1991, 369 (01) :175-178

[3] DETECTION OF A SPECTRAL BREAK IN THE EXTRA HARD COMPONENT OF GRB 090926A [J].

Ackermann, M. ;

Ajello, M. ;

Asano, K. ;

Axelsson, M. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Baring, M. G. ;

Bastieri, D. ;

Bechtol, K. ;

Bellazzini, R. ;

Berenji, B. ;

Bhat, P. N. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bonamente, E. ;

Borgland, A. W. ;

Bouvier, A. ;

Bregeon, J. ;

Brez, A. ;

Briggs, M. S. ;

Brigida, M. ;

Bruel, P. ;

Buehler, R. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caraveo, P. A. ;

Carrigan, S. ;

Casandjian, J. M. ;

Cecchi, C. ;

Celik, O. ;

Chaplin, V. ;

Charles, E. ;

Chekhtman, A. ;

Chiang, J. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Connaughton, V. ;

Conrad, J. ;

Cutini, S. ;

Dermer, C. D. ;

De Angelis, A. ;

De Palma, F. ;

Dingus, B. L. ;

Silva, E. Do Couto E. ;

Drell, P. S. ;

Dubois, R. ;

Favuzzi, C. .

ASTROPHYSICAL JOURNAL, 2011, 729 (02)

[4] FERMI OBSERVATIONS OF GRB 090510: A SHORT-HARD GAMMA-RAY BURST WITH AN ADDITIONAL, HARD POWER-LAW COMPONENT FROM 10 keV TO GeV ENERGIES [J].

Ackermann, M. ;

Asano, K. ;

Atwood, W. B. ;

Axelsson, M. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Baring, M. G. ;

Bastieri, D. ;

Bechtol, K. ;

Bellazzini, R. ;

Berenji, B. ;

Bhat, P. N. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bonamente, E. ;

Borgland, A. W. ;

Bouvier, A. ;

Bregeon, J. ;

Brez, A. ;

Briggs, M. S. ;

Brigida, M. ;

Bruel, P. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caraveo, P. A. ;

Carrigan, S. ;

Casandjian, J. M. ;

Cecchi, C. ;

Celik, Oe. ;

Charles, E. ;

Chiang, J. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Connaughton, V. ;

Conrad, J. ;

Dermer, C. D. ;

de Palma, F. ;

Dingus, B. L. ;

do Couto e Silva, E. ;

Drell, P. S. ;

Dubois, R. ;

Dumora, D. ;

Farnier, C. ;

Favuzzi, C. ;

Fegan, S. J. ;

Finke, J. .

ASTROPHYSICAL JOURNAL, 2010, 716 (02) :1178-1190

[5] Relativistic jets from collapsars [J].

Aloy, MA ;

Müller, E ;

Ibáñez, JM ;

Martí, JM ;

MacFadyen, A .

ASTROPHYSICAL JOURNAL, 2000, 531 (02) :L119-L122

[6] GRB110721A: AN EXTREME PEAK ENERGY AND SIGNATURES OF THE PHOTOSPHERE [J].

Axelsson, M. ;

Baldini, L. ;

Barbiellini, G. ;

Baring, M. G. ;

Bellazzini, R. ;

Bregeon, J. ;

Brigida, M. ;

Bruel, P. ;

Buehler, R. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caraveo, P. A. ;

Cecchi, C. ;

Chaves, R. C. G. ;

Chekhtman, A. ;

Chiang, J. ;

Claus, R. ;

Conrad, J. ;

Cutini, S. ;

D'Ammando, F. ;

de Palma, F. ;

Dermer, C. D. ;

do Couto e Silva, E. ;

Drell, P. S. ;

Favuzzi, C. ;

Fegan, S. J. ;

Ferrara, E. C. ;

Focke, W. B. ;

Fukazawa, Y. ;

Fusco, P. ;

Gargano, F. ;

Gasparrini, D. ;

Gehrels, N. ;

Germani, S. ;

Giglietto, N. ;

Giroletti, M. ;

Godfrey, G. ;

Guiriec, S. ;

Hadasch, D. ;

Hanabata, Y. ;

Hayashida, M. ;

Hou, X. ;

Iyyani, S. ;

Jackson, M. S. ;

Kocevski, D. ;

Kuss, M. ;

Larsson, J. ;

Larsson, S. ;

Longo, F. ;

Loparco, F. .

ASTROPHYSICAL JOURNAL LETTERS, 2012, 757 (02)

[7] BATSE OBSERVATIONS OF GAMMA-RAY BURST SPECTRA .1. SPECTRAL DIVERSITY [J].

BAND, D ;

MATTESON, J ;

FORD, L ;

SCHAEFER, B ;

PALMER, D ;

TEEGARDEN, B ;

CLINE, T ;

BRIGGS, M ;

PACIESAS, W ;

PENDLETON, G ;

FISHMAN, G ;

KOUVELIOTOU, C ;

MEEGAN, C ;

WILSON, R ;

LESTRADE, P .

ASTROPHYSICAL JOURNAL, 1993, 413 (01) :281-292

[8]

Beloborodov A. M., 2012, PREPRINT

[9] RADIATIVE TRANSFER IN ULTRARELATIVISTIC OUTFLOWS [J].

Beloborodov, Andrei M. .

ASTROPHYSICAL JOURNAL, 2011, 737 (02)

[10] Collisional mechanism for gamma-ray burst emission [J].

Beloborodov, Andrei M. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2010, 407 (02) :1033-1047

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