GCN Circular 997

Subject
GRB 010214, I-band data
Event
Date
2001-02-28T16:50:52Z (25 years ago)
From
Sylvio Klose at TLS Tautenburg <klose@tls-tautenburg.de>
S. Klose, B. Stecklum, H. Linz, and U. Laux (Thueringer Landessternwarte 
   Tautenburg) 


report:

The error box of GRB 010214 (Gandolfi et al., GCN #932Loading...
 
 ) was imaged
in the I-band using the Tautenburg Schmidt telescope equipped with
the Schmidt focus CCD camera (2k x 2k). The observing log is as follows:

  Run 1:   Feb 15,  0:55 UT - 1:35 UT  and   2:24 UT - 3:05 UT 
  Run 2:   Feb 16,  2:01 UT - 2:48 UT  and   3:38 UT - 3:48 UT 
  Run 3:   Feb 27,  3:44 UT - 4:24 UT.                         

The R-band afterglow candidate reported by Rol et al. (GCN #955Loading...
 
 ) is
clearly detected on the combined frames taken during the second
observing run. Based on the DSS2 red coordinate system we obtain for this
source RA, DEC (2000) = 17:41:03.0, 48:34:29 (+/- 0.4"). Using the
photometric standards provided by Henden (GCN #988Loading...
 
 ) we measure a mean 
I-band magnitude of 21.9 +/- 0.4 during run 2.

The combined frames of run 1 are somewhat less deep and the same holds for
the combined frames of run 3. The source is also detectable on these
images but very close to the detection limit which excludes an aperture
photometry. However, a visual comparison of the optical appearance of the
afterglow candidate on these images with the optical appearance of a
near-by, faint stellar object at RA, DEC (2000) = 17:41:07.7, 48:35:02
(+/- 0.8") allows us to state that we see no evidence for a fading of the
afterglow candidate between run 1 and run 3. Any fading must be less than
about 0.5 mag.
 
In conclusion, if this source is the combined OT + underlying host
galaxy then even during our first observing run (about 0.7 days after the
burst) the I-band flux of the afterglow did not exceed the I-band flux of
the underlying host by more than about 50 percent.

The I-band image is posted on the Tautenburg Web page at
http://www.tls-tautenburg.de/research/grb010214.html. It can also be
obtained via anonymous ftp from ftp.tls-tautenburg.de, directory
/pub/klose/GCN/.


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