EDP Sciences
Free access
Volume 443, Number 3, December I 2005
Page(s) 841 - 849
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20052898

A&A 443, 841-849 (2005)
DOI: 10.1051/0004-6361:20052898

GRB 021004 modelled by multiple energy injections

A.  de Ugarte  Postigo1, A. J. Castro-Tirado1, J.  Gorosabel1, G.  Jóhannesson2, G.  Björnsson2, E. H. Gudmundsson2, M.  Bremer3, S.  Pak4, N.  Tanvir4, J. M. Castro Cerón5, S.  Guzyi6, 1, M.  Jelínek1, S.  Klose7, D.  Pérez-Ramírez8, J.  Aceituno9, A.  Campo Bagatín10, S.  Covino11, N.  Cardiel9, T.  Fathkullin12, A. A. Henden13, S.  Huferath14, Y.  Kurata15, D.  Malesani11, F.  Mannucci16, P.  Ruiz-Lapuente17, V.  Sokolov12, U.  Thiele9, L.  Wisotzki14, L. A. Antonelli18, C.  Bartolini19, A.  Boattini20, A.  Guarnieri19, A.  Piccioni19, G.  Pizzichini21, M.  del Principe22, A.  di  Paola18, D.  Fugazza23, G.  Ghisellini11, L.  Hunt16, T.  Konstantinova24, N.  Masetti21, E.  Palazzi21, E.  Pian25, M.  Stefanon11, V.  Testa18 and P. J. Tristram26

1  Instituto de Astrofísica de Andalucía (IAA-CSIC), Apartado de Correos 3004, 18080 Granada, Spain
    e-mail: deugarte@iaa.es
2  Science Institute, University of Iceland, Dunhaga 3, IS-107 Reykjavík, Iceland
3  IRAM - Institut de Radio Astronomie Millimétrique, 300 rue de la Piscine, 38406 Saint-Martin d'Hères, France
4  Dept. Physics, Astronomy & Maths, University of Hertfordshire, College Lane, Hatfield, Herts AL10 9AB, UK
5  Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø, Denmark
6  Nikolaev State University, Nikolska 24, 54030 Nikolaev, Ukraine
7  Thüringer Landessternwarte Tautenburg, 07778 Tautenburg, Germany
8  Dpto. de Física (EPS), Universidad de Jaén, 23071 Jaén, Spain
9  Calar Alto Observatory, Apartado de Correos 511, 04080 Almería, Spain
10  Departamento de Física, Universidad de Alicante, Apartado de Correos 99, 03080 Alicante, Spain
11  INAF - Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807 Merate (LC), Italy
12  Special Astrophysical Observatory of the Russian Academy of Sci. (SAO-RAS), Russia
13  US Naval Observatory, Flagstaff, AZ 86001, USA
14  Astrophysikalisches Institut, 14482 Potsdam, Germany
15  Solar Terrestrial Environment Laboratory, Nagoya University, Japan
16  INAF - IRA, Largo E. Fermi 5, 50125 Firenze, Italy
17  Departamento de Astronomía, Universidad de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
18  INAF - Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio Catone, Italy
19  Dipartimento di Astronomia, Universitá di Bologna, via Ranzani 1, 40127 Bologna, Italy
20  INAF - IAS, via Fosso del Cavaliere 100, 00133 Roma, Italy
21  INAF - Istituto di Astrofisica Spaziale e Fisica Cosmica, Sezione di Bologna, via Gobetti 101, 40129 Bologna, Italy
22  INAF - Osservatorio Astronomico di Teramo, via M. Maggini 47, 64100 Teramo, Italy
23  Centro Galileo Galilei, Apartado 565, 38700 Santa Cruz de La Palma, Spain
24  Astronomical Institute of St. Petersburg University, Petrodvorets, Universitetsky pr. 28, 198504 St. Petersburg, Russia
25  INAF - Osservatorio Astronomico di Trieste, via Tiepolo 11, 34131 Trieste, Italy
26  Department of Physics and Astronomy, University of Canterbury, Canterbury, New Zealand

(Received 17 February 2005 / Accepted 20 May 2005 )

GRB 021004 is one of the best sampled gamma-ray bursts (GRB) to date, although the nature of its light curve is still being debated. Here we present 107 new optical, near-infrared (NIR) and millimetre observations, ranging from 2 h to more than a year after the burst. Fitting the multiband data to a model based on multiple energy injections suggests that at least 7 refreshed shocks took place during the evolution of the afterglow, implying a total energy release (collimated within an angle of 1$\fdg$8) of ~ $8 \times 10^{51}$ erg. Analysis of the late photometry reveals that the GRB 021004 host is a low extinction ( $A_{\rm V}\sim0.1$) starburst galaxy with $M_{B}\simeq-22.0$.

Key words: gamma rays: bursts -- galaxies: fundamental parameters -- techniques: photometric

SIMBAD Objects

© ESO 2005