GCN Circular 130

GRB 980703. NEW OPTICAL OBSERVATIONS
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M.R. Zapatero Osorio (Instituto de Astrofisica de Canarias, IAC, 
                      E-38200 La Laguna, Tenerife, Spain)
A. Castro-Tirado     (Laboratorio de Astrofisica Espacial y Fisica
                      Fundamental, LAEFF-INTA, Madrid)
J. Gorosabel         (LAEFF)
A. Oscoz, S. Kemp    (IAC)
F. Frontera, L. Nicastro (on behalf of the BeppoSAX team)
 

Report:

Images in the R-band have been obtained at the 0.8-m IAC80 telescope 
(Teide Observatory) on July 4 and 6 including the BeppoSAX error box 
for the X-ray source 1SAX J235907+0835 presumably related to GRB980703 
which was detected by both BATSE and RXTE.  These data reveal an object 
located at RA = 23h 59m 6.7s  DEC = 8d 35' 7'' (+/- 2'', Eq. J2000) 
which has faded by about 1.5 mag at this wavelength.  A preliminary 
photometric analysis allows us to determine R = 20.6 +/- 0.1 
(July 4.123 UT) and 22.1 +/- 0.2 (July 6.137 UT).  No other objects 
varying by more than 0.2 mag are seen down to a limiting magnitude of 
R = 22.5.  A finder chart is available via anonymous ftp to  
ftp.ll.iac.es (cd publong/grb980703/).