THE OPTICAL LUMINOSITY FUNCTION OF GAMMA-RAY BURSTS DEDUCED FROM ROTSE-III OBSERVATIONS

• Published in: The Astrophysical journal Vol. 795; no. 2; pp. 1 - 6
• Main Authors: Cui, X H, Wu, X F, Wei, J J, Yuan, F, Zheng, W K, Liang, E W, Akerlof, C W, Ashley, M C B, Flewelling, H A, GOGUS, E
• Format: Journal Article
• Language: English
• Published: United States 10.11.2014
• Subjects: AFTERGLOW; Afterglows; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; Computer simulation; COMPUTERIZED SIMULATION; COSMIC GAMMA BURSTS; DECAY; DETECTION; DISTRIBUTION; EMISSION; Fluxes; Gamma ray bursts; LUMINOSITY; MONTE CARLO METHOD; STARS; TRANSIENTS
• ISSN: 1538-4357; 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/795/2/103

We present the optical luminosity function (LF) of gamma-ray bursts (GRBs) estimated from a uniform sample of 58 GRBs from observations with the Robotic Optical Transient Search Experiment III (ROTSE-III). Our GRB sample is divided into two sub-samples: detected afterglows (18 GRBs) and those with upper limits (40 GRBs). We derive R-band fluxes for these two sub-samples 100 s after the onset of the burst. The optical LFs at 100 s are fitted by assuming that the co-moving GRB rate traces the star formation rate. While fitting the optical LFs using Monte Carlo simulations, we take into account the detection function of ROTSE-III. We find that the cumulative distribution of optical emission at 100 s is well described by an exponential rise and power-law decay, a broken power law, and Schechter LFs. A single power-law (SPL) LF, on the other hand, is ruled out with high confidence.