Kocevski, Daniel, Thone, Christina C, Ramirez-Ruiz, Enrico, Bloom, Joshua S., Granot, Jonathan, Butler, Nathaniel R., ...
We present results of an extensive observing campaign of the short duration, hard spectrum gamma-ray burst (GRB) 070724A, aimed at detecting the radioactively-powered emission that might follow from...
Modeling The GRB Host Galaxy Mass Distribution: Are GRBs Unbiased Tracers of Star Formation? (2009)
Kocevski, Daniel, West, Andrew A., Modjaz, Maryam
We model the mass distribution of long gamma-ray burst (GRB) host galaxies given recent results suggesting that GRBs occur in low metallicity environments. By utilizing measurements of the redshift...
Generalized Tests for Selection Effects in GRB High-Energy Correlations (2008)
Butler, Nathaniel R., Kocevski, Daniel, Bloom, Joshua S.
Several correlations among parameters derived from modelling the high-energy properties of GRBs have been reported. We show that well-known examples of these have common features indicative of strong...
GRB Energetics in the Swift Era (2007)
Kocevski, Daniel, Butler, Nathaniel
We examine the rest frame energetics of 76 gamma-ray bursts (GRBs) with known redshift that were detected by the Swift spacecraft and monitored by the satellite's X-ray Telescope (XRT). Using the...
Butler, Nathaniel R., Kocevski, Daniel, Bloom, Joshua S., Curtis, Jason L.
We calculate durations and spectral paramaters for 218 Swift bursts detected by the BAT instrument between and including GRBs 041220 and 070509, including 77 events with measured redshifts....
X-ray Hardness Variations as an Internal/External Shock Diagnostic (2007)
Butler, Nathaniel R., Kocevski, Daniel
The early, highly time-variable X-ray emission immediately following GRBs exhibits strong spectral variations that are unlike the temporally smoother emission which dominates after $t\sim 10^3$ s....
Pulse Width Evolution of Late Time X-rays Flares in GRBs: Evidence For Internal Shocks (2007)
Kocevski, Daniel, Butler, Nathaniel, Bloom, Joshua S.
We study the duration and variability of late time X-ray flares following gamma-ray bursts (GRBs) observed by the narrow field X-ray telescope (XRT) aboard the {\it Swift} spacecraft. These flares...
Kocevski, Daniel, Modjaz, Maryam, Bloom, Joshua S., Foley, Ryan, Starr, Daniel, Blake, Cullen H., ...
We report simultaneous multicolor near-infrared (NIR) observations of the supernova associated with x-ray Flash 060218 during the first 16 days after the high energy event. We find that the light...
No supernovae associated with two long-duration gamma-ray bursts (2006)
Fynbo, Johan P. U., Watson, Darach, Thöne, Christina C., Sollerman, Jesper, Bloom, Joshua S., Davis, Tamara M., ...
It is now accepted that long-duration gamma-ray bursts (GRBs) are produced during the collapse of a massive star(1,2). The standard 'collapsar' model(3) predicts that a broad-lined and luminous type...
Butler, Nathaniel R., Kocevski, Daniel
We show that the X-ray and $\gamma$-ray spectra of Swift GRBs and their afterglows are consistent with the emission characteristic of an expanding, relativistic fireball. The classical afterglow due...
No supernovae associated with two long-duration gamma ray bursts (2006)
Fynbo, Johan P. U., Watson, Darach, Thoene, Christina C., Sollerman, Jesper, Bloom, Joshua S., Davis, Tamara M., ...
It is now accepted that long duration gamma-ray bursts (GRBs) are produced during the collapse of a massive star. The standard "collapsar" model predicts that a broad-lined and luminous Type Ic...
Quantifying the Luminosity Evolution in Gamma-ray Bursts (2006)
Kocevski, Daniel, Liang, Edison
We estimate the luminosity evolution and formation rate for over 900 GRBs by using redshift and luminosity data calculated by Band, Norris, $&$ Bonnell (2004) via the lag-luminosity correlation. By...
No supernovae associated with two long-duration gamma-ray bursts (2006)
Fynbo, Johan P. U., Watson, Darach, Thöne, Christina C., Sollerman, Jesper, Bloom, Joshua S., Davis, Tamara M., ...
No supernovae associated with two long-duration gamma-ray bursts (2006)
Fynbo, Johan P. U., Watson, Darach, Thöne, Christina C., Sollerman, Jesper, Bloom, Joshua S., Davis, Tamara M., ...
The investigation of intrinsic spectral and temporal properties of gamma-ray bursts (2005)
Kocevski, Daniel, Kocevski, Daniel
Gamma-ray bursts (GRBs) have become a truly unique puzzle in Astronomy. Unlike quasars and pulsars which were explained within years of their discovery, the origins of GRBs remain a mystery more then...