TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2380
SUBJECT: XRF 020427: Gemini-South Spectroscopic Observations of the Host
DATE:    03/09/09 18:59:50 GMT
FROM:    Josh Bloom at Harvard/CFA  <jbloom@cfa.harvard.edu>

XRF 020427: Gemini-South Spectroscopic Observations of the Host Galaxy

P. G. van Dokkum (Yale) and J. S. Bloom (CfA) report:

On 1 Sept 2003 UT, we observed the host galaxy of XRF 020427 with the
newly commissioned GMOS Spectrograph on the Gemini South 8 m at CTIO in
Chile. Using the detection of the host continuum down to at least 3800
Angstrom in three blue grating exposures, we place a firm upper limit to
the redshift of the host at z < 2.3. In the presence of strong fringing, a
preliminary reduction reveals a (formally significant) faint emission line
at 8485 Angstrom in two dithered 1200 sec exposures. This line is also
formally detected, blueshifted by about 1800 km/s, in the nearby galaxy to
the South (see Bloom et al. ApJ, in press; astro-ph/0303514), giving added
confidence to the detection and the physical association of these two
galaxies. Without corroboration from other absorption or emission lines,
however, we have been unable to associate this tentative line with a
redshift for the host. A more detailed analysis is in progress."

We thank the Director for Discretionary Time and the observing staff of
Gemini for assistance.