TITLE: GCN GRB OBSERVATION REPORT NUMBER: 96 SUBJECT: GRB980519 Secondary Standards DATE: 98/06/05 00:37:19 GMT FROM: Arne A Henden at USNO/USRA The U. S. Naval Observatory GRB team (A. A. Henden, F. J. Vrba, C. B. Luginbuhl, B. Canzian, S. E. Levine, H. H. Guetter, J. A. Munn) report follow up optical photometry of the secondary standards (see Jaunsen, et. al. GCN 78 and Bloom, et. al. GCN 87) in the field of GRB980519. The observations were made on two photometric nights during the past week with the USNO 1.0m telescope. Johnson BV and Cousins RI filters were used, with an average of 32 Landolt standards of wide color range and extinction observed on each night. The transformations are accurate to 0.01-0.02mag per single observation. DAOPHOT psf fitting was used in the GRB field, with magnitude corrections to adjust the photometry to a standard aperture diameter. Given below is the photometry, with errors based on the variance between the two nights. More detail, including coordinates and comparisons between other published values for these stars, can be found on our Web site at: http://psyche.usno.navy.mil/nofs/grb/grb980519.html For further information contact A. A. Henden at aah@nofs.navy.mil or by telephone at (520) 779-5132. This GCN note can be cited. ID B Berr V Verr R Rerr I Ierr -------------------------------------------------------------- A 19.661 0.114 18.558 0.018 17.914 0.005 17.338 0.027 B 20.218 0.061 19.318 0.027 18.477 0.001 C 19.313 0.060 18.549 0.027 18.029 0.004 17.525 0.004 D 16.433 0.003 15.614 0.005 15.139 0.000 14.686 0.004 E 21.230 0.146 19.998 0.030 18.767 0.022 F 21.174 0.226 19.900 0.109 18.578 0.289 G 19.915 0.006 18.867 0.004 17.999 0.054 H 20.574 0.062 19.432 0.044 17.990 0.050 I 20.054 0.021 19.645 0.042 19.138 0.007 J 20.907 0.036 20.001 0.011 19.148 0.011