GCN Circular 9420
Subject
GRB 090520: GROND upper limits
Date
2009-05-22T23:53:35Z (16 years ago)
From
Andrea Rossi at TLS Tautenburg <rossi@tls-tautenburg.de>
A. Rossi (Tautenburg), T. Kruehler and J. Greiner (both MPE Garching)
report on behalf of the GROND team:
GROND (Greiner et al. 2008, PASP 120, 405) at the 2.2m ESO/MPI telescope at La
Silla Observatory (Chile)
started follow-up observations of GRB 090520 (Cummings et al. 2009, GCN #9417)
on May 21, at 09:35 UTC
(~32 h after the burst). In addition, a second epoch of imaging was obtained,
which started on May 22, 09:37 UTC.
Image subtraction does not reveal any variable source between the two epochs.
The first epoch thus yields the following upper limits:
g > 23.8
r > 24.0
i > 23.4
z > 23.2
J > 21.8
H > 21.4
K > 20.8
obtained using the GROND zeropoints and 2MASS field stars as reference.