GCN Circular 2056
Subject
GRB 030329: optical observations
Event
Date
2003-04-01T02:11:50Z (23 years ago)
From
Jerome A. Orosz at San Diego State U <orosz@zwartgat.sdsu.edu>
J. Brodney Fitzgerald and Jerome A. Orosz (San Diego
State University) report:
We have observed the field of GRB 030329 (Peterson & Price, GCN 1985)
with the 1 meter telescope at the Mount Laguna Observatory (located 45
miles east of downtown San Diego at a dark site in the Cleveland
National Forest at an altitude of 6100 feet or 1859 meters) on the
nights of 2003 March 30 and 31 (UT). We used a Loral 2048 x 2048 CCD
(binned 2 x 2) and Bessell B, V, R, and I filters. Both nights were
photometric. The instrumental time series were obtained using
Stetson's programs DAOPHOT, ALLSTAR, and DAOMASTER. The instrumental
magnitudes were placed on the standard scales using Hendon's (GCN
2023) calibration. Our observations are summarized in the 4 tables
below. The errors quote include only the DAOPHOT errors, and do not
include errors in the zero points (estimated to be a few percent).
The CCD images of the GRB field and some Landolt fields are available
upon request to orosz@sciences.sdsu.edu. Further observations are
planned for the night of April 1 (UT).
We also report the discovery of a possible eclipsing binary in the
field. The J2000 coordinates are 10:44:36.81, +21:26:58.8 (taken from
Hendon's list given in GCN 2023). The star was at a minimum
brightness around March 31 at 4:30 UT. Over the next three hours it
brightened by about 0.6 magnitudes in all the filters. The brightness
level was roughly constant between about 8:10 UT and 11:00 UT. The
star was apparently constant on the night of March 30, although this
conclusion is somewhat weak owing to the fact that it was saturated in
many of our images. The following table gives the extreme magnitudes
observed:
Filter Min Mag Max Mag
-----------------------------
B 14.36 13.77
V 14.00 13.41
R 13.78 13.11
I 13.60 13.00
Our GRB observations follow:
Table 1: B Observations:
date-obs at start exptime mag err
(sec)
-------------------------------------------------
2003-03-30T04:39:56.10 600.000 16.263 0.008
2003-03-30T05:19:08.50 480.000 16.321 0.010
2003-03-30T06:21:03.50 480.000 16.415 0.006
2003-03-30T07:24:03.20 480.000 16.510 0.004
2003-03-30T08:01:23.30 480.000 16.577 0.004
2003-03-30T08:50:07.70 480.000 16.648 0.004
2003-03-30T09:38:09.20 480.000 16.712 0.005
2003-03-30T10:38:02.00 480.000 16.889 0.013
2003-03-31T03:49:47.10 240.000 17.060 0.008
2003-03-31T04:09:46.30 240.000 17.087 0.009
2003-03-31T04:53:02.80 300.000 17.112 0.008
2003-03-31T05:16:57.30 300.000 17.140 0.008
2003-03-31T05:39:42.70 300.000 17.172 0.008
2003-03-31T06:17:01.30 300.000 17.191 0.008
2003-03-31T06:41:33.10 300.000 17.239 0.006
2003-03-31T07:17:46.30 300.000 17.246 0.009
2003-03-31T07:40:25.90 300.000 17.243 0.007
2003-03-31T08:03:53.90 300.000 17.285 0.009
2003-03-31T08:09:22.40 300.000 17.293 0.008
2003-03-31T08:48:31.90 300.000 17.296 0.007
2003-03-31T09:10:50.10 300.000 17.309 0.007
2003-03-31T09:33:07.30 300.000 17.327 0.007
2003-03-31T09:55:57.70 300.000 17.361 0.010
2003-03-31T10:42:17.30 300.000 17.374 0.012
2003-03-31T11:05:04.70 300.000 17.385 0.014
Table 2: V Observations:
date-obs at start exptime mag err
(sec)
-------------------------------------------------
2003-03-30T04:39:56.10 600.000 15.8732 0.011
2003-03-30T05:19:08.50 480.000 15.9492 0.007
2003-03-30T06:21:03.50 480.000 16.0532 0.007
2003-03-30T07:24:03.20 480.000 16.1452 0.004
2003-03-30T08:01:23.30 480.000 16.1642 0.041
2003-03-30T08:50:07.70 480.000 16.2722 0.004
2003-03-30T09:38:09.20 480.000 16.3632 0.005
2003-03-30T10:38:02.00 480.000 16.4142 0.007
2003-03-31T03:54:27.10 240.000 16.6532 0.006
2003-03-31T04:15:22.50 240.000 16.6672 0.011
2003-03-31T04:59:11.40 300.000 16.7222 0.006
2003-03-31T05:22:35.30 300.000 16.7522 0.007
2003-03-31T05:45:20.50 300.000 16.7572 0.008
2003-03-31T06:23:02.00 300.000 16.7942 0.006
2003-03-31T06:47:19.40 300.000 16.8242 0.007
2003-03-31T07:23:20.20 300.000 16.8622 0.006
2003-03-31T07:46:01.50 300.000 16.8722 0.006
2003-03-31T08:14:56.30 300.000 16.8802 0.007
2003-03-31T08:20:24.00 300.000 16.8702 0.007
2003-03-31T08:54:07.40 300.000 16.9002 0.006
2003-03-31T09:16:24.00 300.000 16.9002 0.007
2003-03-31T09:38:42.50 300.000 16.9172 0.007
2003-03-31T10:01:27.30 300.000 16.9292 0.008
2003-03-31T10:06:57.80 300.000 16.4682 0.010
2003-03-31T10:12:26.00 300.000 16.9592 0.009
2003-03-31T10:48:07.50 300.000 16.9402 0.012
2003-03-31T11:10:40.10 300.000 16.9662 0.014
Table 3: R Observations:
date-obs at start exptime mag err
(sec)
-------------------------------------------------
2003-03-30T04:39:56.10 600.000 15.402 0.006
2003-03-30T05:19:08.50 480.000 15.524 0.007
2003-03-30T06:21:03.50 480.000 15.694 0.009
2003-03-30T07:24:03.20 480.000 15.801 0.004
2003-03-30T08:01:23.30 480.000 15.841 0.005
2003-03-30T08:50:07.70 480.000 15.917 0.004
2003-03-30T09:38:09.20 480.000 16.004 0.006
2003-03-30T10:38:02.00 480.000 16.048 0.006
2003-03-31T03:59:42.40 240.000 16.277 0.009
2003-03-31T04:20:13.10 240.000 16.313 0.024
2003-03-31T05:04:46.90 300.000 16.356 0.006
2003-03-31T05:28:31.20 300.000 16.378 0.005
2003-03-31T05:50:50.80 300.000 16.392 0.007
2003-03-31T06:29:05.50 300.000 16.421 0.006
2003-03-31T06:52:51.60 300.000 16.459 0.005
2003-03-31T07:28:53.20 300.000 16.479 0.006
2003-03-31T07:51:53.40 300.000 16.487 0.007
2003-03-31T08:26:10.70 300.000 16.516 0.022
2003-03-31T08:31:42.00 300.000 16.509 0.006
2003-03-31T08:59:40.10 300.000 16.536 0.007
2003-03-31T09:21:55.50 300.000 16.535 0.006
2003-03-31T09:44:13.50 300.000 16.539 0.008
2003-03-31T10:18:09.40 300.000 16.560 0.007
2003-03-31T10:29:22.00 300.000 16.555 0.009
2003-03-31T10:53:41.70 300.000 16.577 0.007
2003-03-31T11:16:11.50 300.000 16.583 0.015
Table 4: I Observations:
date-obs at start exptime mag err
(sec)
-------------------------------------------------
2003-03-30T04:39:56.10 600.000 15.0006 0.009
2003-03-30T05:19:08.50 480.000 15.1076 0.012
2003-03-30T06:21:03.50 480.000 15.2816 0.007
2003-03-30T07:24:03.20 480.000 15.3916 0.004
2003-03-30T08:01:23.30 480.000 15.4266 0.027
2003-03-30T08:50:07.70 480.000 15.5186 0.005
2003-03-30T09:38:09.20 480.000 15.6376 0.008
2003-03-30T10:38:02.00 480.000 15.7036 0.011
2003-03-31T04:04:32.10 240.000 15.8716 0.008
2003-03-31T04:25:02.80 240.000 15.8926 0.010
2003-03-31T05:10:34.50 300.000 15.9396 0.006
2003-03-31T05:34:03.50 300.000 15.9596 0.006
2003-03-31T05:56:25.90 300.000 15.9946 0.006
2003-03-31T06:35:53.60 300.000 16.0276 0.007
2003-03-31T06:58:26.10 300.000 16.0536 0.006
2003-03-31T07:34:51.90 300.000 16.0826 0.008
2003-03-31T07:58:11.70 300.000 16.0746 0.008
2003-03-31T08:37:12.10 300.000 16.0836 0.008
2003-03-31T08:42:40.70 300.000 16.1066 0.006
2003-03-31T09:05:09.40 300.000 16.1026 0.007
2003-03-31T09:27:28.10 300.000 16.1196 0.008
2003-03-31T09:49:53.50 300.000 16.1346 0.009
2003-03-31T10:23:41.20 300.000 16.1386 0.009
2003-03-31T10:35:00.70 300.000 16.1716 0.013
2003-03-31T10:59:14.40 300.000 16.1476 0.012
2003-03-31T11:21:45.60 300.000 16.1626 0.019
References:
Hendon, A., et al. 2003, GCN 2023
Landolt, A. U. 1992, AJ, 104, 340
Peterson, B, A. & Price, P. 2003, GCN 1985
Stetson, P. B. 1987, PASP, 99, 191
-------------------------------------------------------------------------
Jerome A. Orosz
Assistant Professor of Astronomy, San Diego State University
5500 Campanile Drive, San Diego, CA 92182-1221
(619) 594-7118 (office), 594-6182 (dept. secretary), 594-1413 (dept. fax)
http://mintaka.sdsu.edu/faculty/orosz/web/