GCN Circular 2493

J. Hjorth (U. Copenhagen), J. Gorosabel (IAA-CSIC/STScI), B. L. Jensen
(U. Copenhagen), J. P. U. Fynbo (U. Aarhus), M. I. Andersen (AIP),
J. R. Rasmussen (U. Aarhus), T. H. Dall (ESO), D. Bersier (STScI),
D. Watson, K. Pedersen, P. Jakobsson, and H. Pedersen (U. Copenhagen) report:

"We have observed the INTEGRAL error box of GRB 031203 (Gotz et al. GCN #2459)
with the Danish 1.5-m telescope at La Silla. We have obtained ~50 min I-band
exposures at five epochs between Dec 5.6 and Dec 13.6 UT in good seeing
conditions (~ 0.8"). We have performed both SExtractor photometry and
PSF-matched subtraction of the galaxy (Hsia et al. GCN #2470; Prochaska
et al. GCN #2475) coincident with the VLA radio (Frail GCN #2473; Soderberg
et al. GCN #2483) and XMM-Newton X-ray (Santos-Lleo & Calderon GCN #2464;
Rodriguez-Pascual et al. GCN #2474; Tedds et al. GCN #2490) error circles.
We find no evidence for significant variability above a level of 0.02 mag.
The PSF-matched subtraction did not reveal significant residuals either. We
therefore cannot confirm the reported variability (Bailyn et al. GCN #2486).
Assuming a foreground reddening of A_I = 2.01 mag (Schlegel et al. 1998),
these data points rule out a contribution from a SN1998bw-like supernova
redshifted to z = 0.105. There is still room for a fainter supernova, a more
distant supernova, or a supernova with a different lightcurve shape.
Continued monitoring at other observatories would help to constrain these
parameters. The monitoring has ended at the Danish 1.5-m telescope."