TITLE:   GCN CIRCULAR
NUMBER:  766
SUBJECT: GRB000301C, UBVI optical observations
DATE:    00/08/03 04:01:59 GMT
FROM:    Krzysztof Z. Stanek at CfA  <kstanek@cfa.harvard.edu>

K. Z. Stanek (CfA), P. Garnavich (Notre Dame), P. Barmby, S. Jha (CfA)
report:

Given the microlensing interpretation of GRB000301C (Garnavich, Loeb &
Stanek 2000b: astro-ph/0008049) and the importance of any additional
data for this burst, we reduced several additional frames of the
optical counterpart of GRB000301C obtained with the FLWO 1.2m
telescope and UBVI filters on 2000 Mar. 4 (UT).

Our measurements are based on the comparison star A of Garnavich et
al. (2000a: GCN 573), calibrated by Henden (2000: GCN 583) (magnitudes
given by Jensen et al. 2000: astro-ph/0005609). We obtain the
following values:

	  Mar. 4.5097 UT   U=20.89 \pm 0.13
	  Mar. 4.499  UT   B=21.49 \pm 0.05
	  Mar. 4.478  UT   V=20.98 \pm 0.05
	  Mar. 4.485  UT   I=20.28 \pm 0.07

As discussed by Garnavich et al. (2000b), to take full advantage of
this unique burst a uniform reduction of all CCD data available would
be most desired. To encourage such an endeavor, we make all our CCD
data (seven 1kx1k frames; see also GCN 573 and 581) publicly available
through the anonymous ftp at

ftp://cfa-ftp.harvard.edu/pub/kstanek/GRB000301C/

Please contact K. Z. Stanek (kstanek@cfa.harvard.edu) if you have any
questions concerning the data.

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