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GCN Circular 297

GRB 990506: Limits on the possible optical transient
1999-05-07T18:58:14Z (25 years ago)
George Djorgovski at Caltech/Palomar <>
GRB 990506: Limits on the possible optical transient

W. L. W. Sargent, T. A. Small, D. T. Frayer, S. R. Kulkarni, S. G. Djorgovski,
J. S. Bloom (Caltech) report on behalf of the Caltech-CARA-NRAO Collaboration:

A spectrum of the possible optical counterpart of GRB 990506 proposed by Vrba
et al. (GCN 294) was obtained at the Keck-II 10-m telescope by Sargent and
Small on 7 May 1999 UT.  This object is a Galactic M-type star, and is thus
presumably unrelated to the burst (cf. also Halpern, GCN 296).

Images of the XTE/IPN error box were obtained at the Palomar 60-inch telescope
by Frayer on 7 May 1999 UT, reaching considerably deeper than the DSS.  No new
optical objects brighter than the DSS limit were found.  Furhter imaging 
observations are planned.

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