Looking into the fireball: rotse-III and swift observations of early gamma-ray burst afterglows

Warning The system is temporarily closed to updates for reporting purpose.

Rykoff, E. S. and Aharonian, F. and Akerlof, C. W. and Ashley, M. C. B. and Barthelmy, S. D. and Flewelling, H. A. and Gehrels, N. and Göğüş, Ersin and Güver, T. and Kızıloğlu, Ü. and Krimm, H. A. and McKay, T. A. and Özel, M. and Phillips, A. and Quimby, R. M. and Rowell, G. and Rujopakarn, W. and Schaefer, B. E. and Smith, D. A. and Vestrand, W. T. and Wheeler, J. C. and Wren, J. and Yuan, F. and Yost, S. A. (2009) Looking into the fireball: rotse-III and swift observations of early gamma-ray burst afterglows. The Astrophysical Journal, 702 (1). pp. 489-505. ISSN 0004-637X

PDF (This is a RoMEO green publisher -- author can archive pre-print (ie pre-refereeing), post-print (ie final draft post-refereeing) and publisher's version/PDF) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader

Official URL: http://dx.doi.org/10.1088/0004-637X/702/1/489


We report on a complete set of early optical afterglows of gamma-ray bursts (GRBs) obtained with the Robotic Optical Transient Search Experiment (ROTSE-III) telescope network from 2005 March through 2007 June. This set is comprised of 12 afterglows with early optical and Swift/X-Ray Telescope observations, with a median ROTSE-III response time of 45 s after the start of gamma-ray emission (8 s after the GCN notice time). These afterglows span 4 orders of magnitude in optical luminosity, and the contemporaneous X-ray detections allow multi-wavelength spectral analysis. Excluding X-ray flares, the broadband synchrotron spectra show that the optical and X-ray emission originate in a common region, consistent with predictions of the external forward shock in the fireball model. However, the fireball model is inadequate to predict the temporal decay indices of the early afterglows, even after accounting for possible long-duration continuous energy injection. We find that the optical afterglow is a clean tracer of the forward shock, and we use the peak time of the forward shock to estimate the initial bulk Lorentz factor of the GRB outflow, and find 100 less than or similar to Gamma(0) less than or similar to 1000, consistent with expectations.

Item Type:Article
Uncontrolled Keywords:gamma rays: bursts
Subjects:Q Science > QB Astronomy > QB460-466 Astrophysics
ID Code:12649
Deposited By:Ersin Göğüş
Deposited On:13 Nov 2009 10:04
Last Modified:23 Jul 2019 15:46

Repository Staff Only: item control page