Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-04-13
Astron.J. 133 (2007) 122-129
Astronomy and Astrophysics
Astrophysics
22 pages, 5 figures, LaTeX, AASTeX 5.2 Minor changes made in response to the referee's report
Scientific paper
10.1086/509656
We present ultraviolet, optical, and infrared photometry of the afterglow of the X-ray flash XRF 050416A taken between approximately 100 seconds and 36 days after the burst. We find an intrinsic spectral slope between 1930 and 22,200 Angstrom of beta = -1.14 +/- 0.20 and a decay rate of alpha = -0.86 +/- 0.15. There is no evidence for a change in the decay rate between approximately 0.7 and 4.7 days after the burst. Our data implies that there is no spectral break between the optical and X-ray bands between 0.7 and 4.7 days after the burst, and is consistent with the cooling break being redward of the K_s band (22,200 Angstrom) at 0.7 days. The combined ultraviolet/optical/infrared spectral energy distribution shows no evidence for a significant amount of extinction in the host galaxy along the line of sight to XRF 050416A. Our data suggest that the extragalactic extinction along the line of sight to the burst is only approximately A_V = 0.2 mag, which is significantly less than the extinction expected from the hydrogen column density inferred from $X$-ray observations of XRF 050416A assuming a dust-to-gas ratio similar to what is found for the Milky Way. The observed extinction, however, is consistent with the dust-to-gas ratio seen in the Small Magellanic Cloud. We suggest that XRF 050416A may have a two-component jet similar to what has been proposed for GRB 030329. If this is the case the lack of an observed jet break between 0.7 and 42 days is an illusion due to emission from the wide jet dominating the afterglow after approximately 1.5 days.
Augusteijn Th.
Blustin Alexander J.
Boyd Patricia T.
Breeveld Alice A.
de Pasquale Massimiliano
No associations
LandOfFree
Optical, Infrared, and Ultraviolet Observations of the X-Ray Flash GRB 050416A does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Optical, Infrared, and Ultraviolet Observations of the X-Ray Flash GRB 050416A, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical, Infrared, and Ultraviolet Observations of the X-Ray Flash GRB 050416A will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-514591