GCN Circular 6926
Subject
GRB 071013: TLS 2nd epoch - Kornienko candidate constant
Event
Date
2007-10-16T19:51:44Z (18 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
D. A. Kann, C. Hoegner, U. Laux & R. Filgas (TLS Tautenburg) report:
We observed the field of GRB 071013 (Marshall et al., GCN 6907) with the
Tautenburg 1.34m Schmidt telescope under good conditions, obtaining 6 300
second images in the Rc band at 3.2 days after the GRB. We use the same
comparison star as given in Kann, Hoegner & Filgas (GCN 6917), and find
the following magnitudes of the possible variable source discovered by
Kornienko et al. (GCN 6925):
Date Mid-Time Rc dRc
13.74086 0.23439 19.537 0.027
13.75231 0.24584 19.506 0.028
13.76103 0.25456 19.634 0.040
13.76977 0.26330 19.566 0.032
13.77850 0.27203 19.704 0.036
13.78723 0.28076 19.629 0.038
13.79596 0.28950 19.683 0.045
13.80469 0.29822 19.593 0.044
13.81342 0.30695 19.589 0.038
13.82216 0.31569 19.635 0.028
13.83088 0.32441 19.598 0.044
13.83961 0.33314 19.572 0.040
13.84834 0.34187 19.762 0.054
Thus, we see no significant variability in the source over the span from
0.23 to 0.34 days after the GRB.
For the second epoch, we combine the 6 300 second images and find, using
the same comparison star:
Date Mid-Time Rc dRc
16.75845 3.25198 19.583 0.015
Thus, we also see no variability between 0.3 and 3.3 days after the GRB.
If this source is at low redshift and possibly associated with a
supernova, there is no evidence for it yet. Further photometric follow-up
and spectroscopy of the USNO/DSS source is encouraged.
This message may be cited.