GCN Circular 14070
Subject
GRB 121212A: Keck observations
Date
2012-12-12T17:24:46Z (11 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley and A. Horesh (Caltech) report:
We slewed to the position of GRB121212A (rupe et al., GCN 14064) with
the Keck I telescope (+LRIS) and acquired a series of exposures with the
slit guider beginning at 15:40 UT, 8.7 hours after the event.
We identified a source near the DSS limit consistent with the XRT
position, at coordinates (J2000) of:
RA = 11:51:10.43
Dec = +78:02:15.3
(+/- 1.5 arcsec)
This is consistent with the XRT and UVOT positions (Beardmore et al.,
GCN 14066; Kuin et al., GCN 14069).
The magnitude is approximately R~21 on the guider camera at this time.
A series of 600s spectroscopic exposures were then taken during
brightening morning twilight.
A provisional reduction of the (low S/N) spectrum shows a significant
flux across the spectral range, extending to at least 3500 Angstroms
with no break or strong absorption lines, suggesting z ~< 2 and
consistent with the detection in the UVOT u filter. Analysis is ongoing.