[vsnet-grb-info 8094] GRB 090609: PAIRITEL NIR Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9628
SUBJECT: GRB 090609: PAIRITEL NIR Upper Limits
DATE:    09/07/09 08:58:46 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan at gmail.com>

A. N. Morgan, C. R. Klein, D. A. Perley, J. S. Bloom, (UC Berkeley), report:

We observed the field of GRB 090709 (Morris et al., GCN 9625) with the
1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at
2009-07-09 07:40:22 UT, ~108 seconds after the Swift trigger.  In
preliminary mosaics (effective exposure time of ~374 seconds) taken
simultaneously in the J, H, and Ks filters, we detect no source at the
XRT position.

The preliminary photometry yields:

post_burst
t_mid(s) exp(s)  filt  U. Limit (3 sig)
438       374     J     > 17.7
438       374     H     > 16.9
438       374     Ks    > 15.3

All magnitudes given in the Vega system, calibrated to 2MASS.  No
correction for Galactic extinction has been made to the above reported
values.  Observations are ongoing.