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GCN Circular 358

Optical Observations of GRB990627
1999-06-30T17:59:18Z (25 years ago)
Elena Pian at ITESRE-CNR,Bologna <>
Optical Observations of GRB990627

E. Rol (U. of Amsterdam), E. Palazzi, N. Masetti, E. Pian, F. Frontera
(TeSRE, CNR, Bologna), T.J. Galama, P.M. Vreeswijk, J. van Paradijs (U. of
Amsterdam), C. Kouveliotou (NASA/MSFC), G. Bakos, K. Sahu (STScI), P.
Sackett (U. of Groningen), J. Menzies (SAAO), L. Nicastro (IFCAI, CNR,
Palermo), E. Costa, (IAS, CNR, Rome), on behalf of a large collaboration
including the PLANET Team and the BeppoSAX GRB optical follow-up Team,

"We have observed the error box of GRB990627 (Gandolfi, GCN #356)
with the Sutherland 1.0m telescope (South Africa) in the R band
on June 28.138-28.193, for a total exposure time of 4200 sec.
Comparison of the summed image with the DSS (2nd Epoch Survey of the
UK Schmidt; RG610 filter) does not show evidence of any new source above
the DSS plate limit.

Photometry linked to the USNO-A1.0 star at RA = 01h 48m 15s.61, Dec = -77o
04' 37".1 (J2000), which has R = 15.8, implies a 3-sigma magnitude limit
of R ~ 21 for the sum image.

We have also inspected the positions of the four radio sources found by
Subrahmanyan et al. (GCN #357) in the GRB990627  error box.
No object brighter than our limiting magitude is seen at any of them.

This message can be cited."
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