Prompt optical observations of GRB 050319 with the Swift UVOT

Mason K., Blustin A., Boyd P., Holland S., Page M., Roming P., ...More

ASTROPHYSICAL JOURNAL, vol.639, no.1, pp.311-315, 2006 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 639 Issue: 1
  • Publication Date: 2006
  • Doi Number: 10.1086/499293
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.311-315
  • Keywords: astrometry, galaxies : distances and redshifts, gamma rays : bursts, shock waves, X-rays : individual (GRB 050319), GAMMA-RAY BURST, INFRARED-EMISSION, REVERSE SHOCK, AFTERGLOW, TELESCOPE, RADIATION, MISSION
  • Istanbul University Affiliated: No


The UVOT telescope on the Swift observatory has detected optical afterglow emission from GRB 050319. The flux declined with a power-law slope of alpha = -0.57 between the start of observations some 230 s after the burst onset (90 s after the burst trigger) until it faded below the sensitivity threshold of the instrument after similar to 5 x 10(4) s. There is no evidence for the rapidly declining component in the early light curve that is seen at the same time in the X-ray band. The afterglow is not detected in UVOT shortward of the B band, suggesting a redshift of about 3.5. The optical V-band emission lies on the extension of the X-ray spectrum, with an optical-to-X-ray slope of beta = 0.8. The relatively flat decay rate of the burst suggests that the central engine continues to inject energy into the fireball for as long as a few x 10(4) s after the burst.