TITLE: GCN GRB OBSERVATION REPORT NUMBER: 39 SUBJECT: GRB980329 near IR observations DATE: 98/04/03 04:43:52 GMT FROM: Don Lamb at U. of Chicago J. M. Quashnock, D. E. Vanden Berk, D. M. Cole, A. R. Cooray, D. Q. Lamb, F. J. Castander, K. Gloria, and D. Long, University of Chicago, on behalf of the Astrophysical Research Consortium (ARC), report: "Between Apr. 1.167 UT and Apr. 1.277, we made near-infrared observations of a region of the sky that includes the entire SAX NFI error box for GRB 980329 (IAUC 6853, 6854), using the GRIM II instrument mounted on the ARC 3.5-m telescope at Apache Point Observatory. At the epoch Apr. 1.167-1.177 and at a position R.A. = 7h02m38s.7, Decl.= +38o50'27" (J2000.0) consistent with that of the R=20.6 object reported in IAUC 6856, we find an object of magnitude J = 17.7 +/- 0.1. This object is approximately 6.4" South and 3.0" West of the bright R=15.8 star reported in IAUC 6856, for which we measure J = 13.9 +/- 0.1. At the epoch Apr. 1.267-1.277 (approximately 2.5 hours later), we find no measurable change (less than approximately 0.1 mag) in the J magnitude of the object." This report is citable.