SCUBA sub-millimeter observations of gamma-ray bursts

Abstract

SCUBA sub-millimeter observations of gamma-ray bursts -III. GRB 030329: the brightest sub-millimeter afterglow to date Smith, I.A.; Tilanus, R.P.J.; Tanvir, N.; Wijers, R.A.M.J.; Vreeswijk, P.; Rol, E.; Kouveliotou, C. General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Abstract. We present all the Target of Opportunity (ToO) sub-millimeter observations of GRB 030329 taken by the Sub-millimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). This was by far the brightest sub-millimeter afterglow seen to date. The flux density at 850 µm was approximately constant up to a break that took place ∼7 days after the burst. This was consistent with being a jet break. The 850 µm results agree with those at longer wavelengths that show a brighter flux ∼7 days after the burst, right at the time of the break. No short-lived large-scale brightenings were detected in the sub-millimeter light curve. However, the 850 µm light curve may have had a drop < ∼ 16 days after the burst. The peak of the afterglow emission was at ∼90 GHz in the days before the break in the light curve. A simple modeling is consistent with the spectral indices remaining the same as the afterglow evolved, with the breaks in the spectrum moving to longer wavelengths at later times and the flux at the peak falling. No significant sub-millimeter emission was detected from the host galaxy.Key words. gamma rays: bursts -submillimeter IntroductionThe discovery of localized transients in the error boxes of gamma-ray burst (GRB) sources has led to intense multiwavelength campaigns that have revolutionized our understanding of these sources. For reviews see Van Paradijs et al. (2000) and Mészáros (2002).Sub-millimeter observations form a key element of the multiwavelength observations of the afterglow. They provide "clean" measures of the source intensity, unaffected by scintillation and extinction. We have therefore been performing Target of Opportunity (ToO) sub-millimeter observations of GRB counterparts using the Sub-millimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT) on Mauna Kea, Hawaii.Including the results shown here, SCUBA has so far performed ToO observations of 23 bursts (Smith et al. 1999(Smith et al. , 2000(Smith et al. , 2001(Smith e...

SCUBA sub-millimeter observations of gamma-ray bursts

“…The redshifts of GRBs 030115 and 030226 were > ∼ 2. Adding all the bursts presented here and GRB 030329 (Smith et al 2005) to Table 2 of Tanvir et al (2004), there are now 8/26 host galaxies with measured redshifts > ∼ 2. The lack of new detections adds to the indication that GRBs are not closely linked to the most luminous dusty star-forming galaxies.…”

“…We therefore simply quote here the flux densities that we find for the new bursts. These can be directly compared to the previous results (Smith et al 2001(Smith et al , 2005Barnard et al 2003;Berger et al 2003;Tanvir et al 2004). …”

“…The most significant afterglow emission observed by SCUBA to date was from GRB 030329 (Smith et al 2005). This had a ∼31 mJy flux density at 850 µm that was essentially constant up to ∼7 days after the burst.…”

“…Galama et al 1998Galama et al , 1999Smith et al 2005) and theories (e.g. Sari et al 1998;Piran 1999;Granot et al 2000;Sari & Mészáros 2000;Chevalier & Li 2000;Granot & Sari 2002;Panaitescu & Kumar 2004;Inoue et al 2005) show that for some bursts the reverse shock and/or afterglow emission can peak in the sub-millimeter in the hours to weeks following the burst.…”

“…GRB 010222 was described in . In this paper, we present all the ToO observations of GRBs made by SCUBA from March 2001 through April 2005, with the exception of GRB 030329, which was discussed in Smith et al (2005). The results shown here are for GRBs 021004, 021211, 030115, 030226, and 041006.…”