TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2022 SUBJECT: GRB030329, SPM optical observations DATE: 03/03/30 12:29:57 GMT FROM: Sergej Zharikov at OAN IA UNAM S. Zharikov (OAN SPM, IA UNAM, Mexico), E. Benitez, J. Torrealba, J. Stepanian (IA UNAM, Mexico) report: We have observed the GRB030329 OT found by B.A. Peterson and P.A. Price (GCN 1985) with 1.5m and 2.1m telescopes of SPM Observatory, BC, Mexico. A set of exposures in UBVRI Bessel filters was obtained with 1.5m telescope under photometric conditions. Standard stars RU 149 and PG 1633+099 from Landolt's catalogue were used for photometric calibrations. The results of photometry are following: 30 March U B V R I UT 03:55 15.23 16.00 15.68 15.38 14.95 UT 05:55 15.44 16.25 15.92 15.61 15.19 UT 08:00 15.80 16.44 16.16 15.84 15.41 UT 10:16 15.99 16.65 16.40 16.05 15.62 Errors are about 0.02. USNO U1050_06350247 star with coordinates (AR=10 44 42; DEC=+21 32 32, J2000) can be used as the secondary standard in the OT field: B = 17.93(5); V =16.84(3); R = 16.04(2); I = 15.48(2) The continuous light curve in the R band with exposures 240 and 120 sec was obtained during 6.5h from 03:55 UT utill 10:40 UT. We estimate the decline rate to be about 0.11 mag/hour. Spectra of the optical afterglow of GRB 030329 were obtained with the 2.1-m telescope and B&Ch spectrograph (600l/mm) starting at 05:22 UT. The spectra cover the wavelength range of 3900 to 6100 AA with a resolution of 2.2A/pix. Data analysis is in progress. This message may be cited.