GCN Circular 4600
Subject
Refined XRT Position for GRB 060123
Event
Date
2006-01-25T20:30:16Z (19 years ago)
From
Josh Bloom at UC Berkeley <jbloom@astron.berkeley.edu>
N. Butler and J. S. Bloom (UC Berkeley):
We determine a refined XRT positions for GRB060123 (Palmer et al.,
GCN 4584)
by matching the positions of X-ray sources to positions of SDSS
sources. A
similar procedure was employed in GCN 4500 to refine the XRT position
for
GRB060108. Using 4 X-ray sources detected in 4.5 ksec of PC mode data
and 6 SDSS sources, we determine a frame offset for the XRT of:
Frame Offset: RA -2.28 ; Dec 2.0 , 90% Conf. Error: 2.7"
Our refined XRT position for GRB060123 is then:
RA 11h 58m 47.66s ; DEC +45d 30' 50.55"
+/-
3.1" (90% Conf.)
This refined XRT position is coincident with the SDSS galaxy noted in
Bloom et al. (GCN 4595). Given this, we suggest that this
coincidence appears to disfavor the high-redshift hypothesis for the
burst (Palmer et al., GCN 4584)."
The X-ray/optical source offsets are shown at:
http://astro.berkeley.edu/~nat/060123/crosscor_sdss.jpg
The XRT overlap atop the SDSS and PAIRITEL images is:
http://astro.berkeley.edu/~jbloom/grb060123-nat.ps.gz
We thank Dave Burrows at PSU for his assistance.