Anomalies in low-energy gamma-ray burst spectra with the Fermi Gamma-ray Burst Monitor

被引:10
作者
Tierney, D. [1 ]
McBreen, S. [1 ]
Preece, R. D. [2 ]
Fitzpatrick, G. [1 ]
Foley, S. [1 ]
Guiriec, S. [3 ]
Bissaldi, E. [4 ]
Briggs, M. S. [2 ]
Burgess, J. M. [2 ]
Connaughton, V. [2 ]
Goldstein, A. [2 ]
Greiner, J. [5 ]
Gruber, D. [5 ]
Kouveliotou, C. [6 ]
McGlynn, S. [5 ,7 ]
Paciesas, W. S. [8 ]
Pelassa, V. [2 ]
von Kienlin, A. [5 ]
机构
[1] Univ Coll Dublin, Dublin 4, Ireland
[2] Univ Alabama, Dept Phys, Huntsville, AL 35805 USA
[3] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA
[4] Univ Innsbruck, Inst Astro & Particle Phys, A-6020 Innsbruck, Austria
[5] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany
[6] NASA, Space Sci Off, VP62, Marshall Space Flight Ctr, Huntsville, AL 35812 USA
[7] Tech Univ Munich, D-85748 Garching, Germany
[8] Univ Space Res Assoc, Inst Sci & Technol, Huntsville, AL 35805 USA
基金
爱尔兰科学基金会;
关键词
gamma-ray burst: general; methods: data analysis; techniques: spectroscopic; LARGE-AREA TELESCOPE; 1ST; 2; YEARS; GRB; 090902B; BATSE OBSERVATIONS; SGR J1550-5418; EMISSION; COMPONENT; GBM; CATALOG; LONG;
D O I
10.1051/0004-6361/201220710
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Context. A Band function has become the standard spectral function used to describe the prompt emission spectra of gamma-ray bursts (GRBs). However, deviations from this function have previously been observed in GRBs detected by BATSE and in individual GRBs from the Fermi era. Aims. We present a systematic and rigorous search for spectral deviations from a Band function at low energies in a sample of the first two years of high fluence, long bursts detected by the Fermi Gamma-ray Burst Monitor (GBM). The sample contains 45 bursts with a fluence greater than 2 x 10(-5) erg/cm(2) (10-1000 keV). Methods. An extrapolated fit method is used to search for low-energy spectral anomalies, whereby a Band function is fit above a variable low-energy threshold and then the best fit function is extrapolated to lower energy data. Deviations are quantified by examining residuals derived from the extrapolated function and the data and their significance is determined via comprehensive simulations which account for the instrument response. This method was employed for both time-integrated burst spectra and time-resolved bins defined by a signal-to-noise ratio of 25 sigma and 50 sigma. Results. Significant deviations are evident in 3 bursts (GRB 081215A, GRB090424 and GRB090902B) in the time-integrated sample (similar to 7%) and 5 bursts (GRB 090323, GRB090424, GRB090820, GRB090902B and GRB090926A) in the time-resolved sample (similar to 11%). Conclusions. The advantage of the systematic, blind search analysis is that it can demonstrate the requirement for an additional spectral component without any prior knowledge of the nature of that extra component. Deviations are found in a large fraction of high fluence GRBs; fainter GRBs may not have sufficient statistics for deviations to be found using this method.
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页数:15
相关论文
共 81 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]   Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C [J].
Abdo, A. A. ;
Ackermann, M. ;
Arimoto, M. ;
Asano, K. ;
Atwood, W. B. ;
Axelsson, M. ;
Baldini, L. ;
Ballet, J. ;
Band, D. L. ;
Barbiellini, G. ;
Baring, M. G. ;
Bastieri, D. ;
Battelino, M. ;
Baughman, B. M. ;
Bechtol, K. ;
Bellardi, F. ;
Bellazzini, R. ;
Berenji, B. ;
Bhat, P. N. ;
Bissaldi, E. ;
Blandford, R. D. ;
Bloom, E. D. ;
Bogaert, G. ;
Bogart, J. R. ;
Bonamente, E. ;
Bonnell, J. ;
Borgland, A. W. ;
Bouvier, A. ;
Bregeon, J. ;
Brez, A. ;
Briggs, M. S. ;
Brigida, M. ;
Bruel, P. ;
Burnett, T. H. ;
Burrows, D. ;
Busetto, G. ;
Caliandro, G. A. ;
Cameron, R. A. ;
Caraveo, P. A. ;
Casandjian, J. M. ;
Ceccanti, M. ;
Cecchi, C. ;
Celotti, A. ;
Charles, E. ;
Chekhtman, A. ;
Cheung, C. C. ;
Chiang, J. ;
Ciprini, S. ;
Claus, R. ;
Cohen-Tanugi, J. .
SCIENCE, 2009, 323 (5922) :1688-1693
[3]   CONSTRAINING THE HIGH-ENERGY EMISSION FROM GAMMA-RAY BURSTS WITH FERMI [J].
Ackermann, M. ;
Ajello, M. ;
Baldini, L. ;
Barbiellini, G. ;
Baring, M. G. ;
Bechtol, K. ;
Bellazzini, R. ;
Blandford, R. D. ;
Bloom, E. D. ;
Bonamente, E. ;
Borgland, A. W. ;
Bottacini, E. ;
Bouvier, A. ;
Brigida, M. ;
Buehler, R. ;
Buson, S. ;
Caliandro, G. A. ;
Cameron, R. A. ;
Cecchi, C. ;
Charles, E. ;
Chekhtman, A. ;
Chiang, J. ;
Ciprini, S. ;
Claus, R. ;
Cohen-Tanugi, J. ;
Cutini, S. ;
D'Ammando, F. ;
de Palma, F. ;
Dermer, C. D. ;
do Couto e Silva, E. ;
Drell, P. S. ;
Drlica-Wagner, A. ;
Favuzzi, C. ;
Fukazawa, Y. ;
Fusco, P. ;
Gargano, F. ;
Gasparrini, D. ;
Gehrels, N. ;
Germani, S. ;
Giglietto, N. ;
Giordano, F. ;
Giroletti, M. ;
Glanzman, T. ;
Granot, J. ;
Grenier, I. A. ;
Grove, J. E. ;
Hadasch, D. ;
Hanabata, Y. ;
Harding, A. K. ;
Hays, E. .
ASTROPHYSICAL JOURNAL, 2012, 754 (02)
[4]   FERMI DETECTION OF γ-RAY EMISSION FROM THE M2 SOFT X-RAY FLARE ON 2010 JUNE 12 (vol 745, pg 144,2012) [J].
Ackermann, M. ;
Ajello, M. ;
Allafort, A. ;
Atwood, W. B. ;
Baldini, L. ;
Barbiellini, G. ;
Bastieri, D. ;
Bechtol, K. ;
Bellazzini, R. ;
Bhat, P. N. ;
Blandford, R. D. ;
Bonamente, E. ;
Borgland, A. W. ;
Bregeon, J. ;
Briggs, M. S. ;
Brigida, M. ;
Bruel, P. ;
Buehler, R. ;
Burgess, J. M. ;
Buson, S. ;
Caliandro, G. A. ;
Cameron, R. A. ;
Casandjian, J. M. ;
Cecchi, C. ;
Charles, E. ;
Chekhtman, A. ;
Chiang, J. ;
Ciprini, S. ;
Claus, R. ;
Cohen-Tanugi, J. ;
Connaughton, V. ;
Conrad, J. ;
Cutini, S. ;
Dennis, B. R. ;
de Palma, F. ;
Dermer, C. D. ;
Digel, S. W. ;
do Couto e Silva, E. ;
Drell, P. S. ;
Drlica-Wagner, A. ;
Dubois, R. ;
Favuzzi, C. ;
Fegan, S. J. ;
Ferrara, E. C. ;
Fortin, P. ;
Fukazawa, Y. ;
Fusco, P. ;
Gargano, F. ;
Germani, S. ;
Giglietto, N. .
ASTROPHYSICAL JOURNAL, 2012, 748 (02)
[5]   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)
[6]   HADRONIC MODELS FOR THE EXTRA SPECTRAL COMPONENT IN THE SHORT GRB 090510 [J].
Asano, Katsuaki ;
Guiriec, Sylvain ;
Meszaros, Peter .
ASTROPHYSICAL JOURNAL LETTERS, 2009, 705 (02) :L191-L194
[7]   THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION [J].
Atwood, W. B. ;
Abdo, A. A. ;
Ackermann, M. ;
Althouse, W. ;
Anderson, B. ;
Axelsson, M. ;
Baldini, L. ;
Ballet, J. ;
Band, D. L. ;
Barbiellini, G. ;
Bartelt, J. ;
Bastieri, D. ;
Baughman, B. M. ;
Bechtol, K. ;
Bederede, D. ;
Bellardi, F. ;
Bellazzini, R. ;
Berenji, B. ;
Bignami, G. F. ;
Bisello, D. ;
Bissaldi, E. ;
Blandford, R. D. ;
Bloom, E. D. ;
Bogart, J. R. ;
Bonamente, E. ;
Bonnell, J. ;
Borgland, A. W. ;
Bouvier, A. ;
Bregeon, J. ;
Brez, A. ;
Brigida, M. ;
Bruel, P. ;
Burnett, T. H. ;
Busetto, G. ;
Caliandro, G. A. ;
Cameron, R. A. ;
Caraveo, P. A. ;
Carius, S. ;
Carlson, P. ;
Casandjian, J. M. ;
Cavazzuti, E. ;
Ceccanti, M. ;
Cecchi, C. ;
Charles, E. ;
Chekhtman, A. ;
Cheung, C. C. ;
Chiang, J. ;
Chipaux, R. ;
Cillis, A. N. ;
Ciprini, S. .
ASTROPHYSICAL JOURNAL, 2009, 697 (02) :1071-1102
[8]   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)
[9]   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
[10]  
Bhat PN, 2011, B ASTRON SOC INDIA, V39, P471