HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA spectroscopy

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Replaced by final version. 10 p., 2 fig. Scheduled to appear in ApJ 555 n2 Jul 10, 2001. Minor changes, both redshift and mean

Scientific paper

10.1086/321585

We present HST/STIS observations of the optical counterpart (OT) of the gamma-ray burster GRB 000301C obtained on 2000 March 6, five days after the burst. CCD clear aperture imaging reveals a R ~ 21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150 < lambda/A < 3300 NUV-MAMA prism spectrum shows a relatively flat continuum (in f_lambda) between 2800 and 3300 A, with a mean flux 8.7 (+0.8,-1.6)+/- 2.6 10^(-18) ergs/s/cm^2/A, and a sharp break centered at 2797+/-25 A. We interpret it as HI Lyman break at z = 2.067+/-0.025 indicating the presence of a cloud with a HI column density log(HI) > 18 on the line-of-sight to the OT. This value is conservatively a lower limit to the GRB redshift. However, the facts that large N(HI) system are usually considered as progenitors of present day galaxies and that other OTs are found associated with star forming galaxies strongly suggest that it is the GRB redshift. In any case, this represents the largest direct redshift determination of a gamma-ray burster to date. Our data are compatible with an OT spectrum represented by a power-law with an intrinsic index \alpha = 1.2((f_nu \propto nu^-alpha) and no extinction in the host galaxy or with alpha = 0.5 and extinction by a SMC-like dust in the OT rest-frame with A_V = 0.15. The large N(HI) and the lack of detected host is similar to the situation for damped Ly-alpha absorbers at z > 2.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA spectroscopy 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 HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA spectroscopy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA spectroscopy will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-15168

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.