GCN Circular 10648
Subject
GRB 100418A: Continued PAIRITEL NIR Observations
Event
Date
2010-04-22T12:36:14Z (16 years ago)
From
Adam Morgan at U.C. Berkeley <qmorgan@gmail.com>
A. N. Morgan, D. A. Perley, C. R. Klein, and J. S. Bloom (UC Berkeley) report:
We continued to observe the location of the optical afterglow of GRB
100418A (Marshall et al., GCN 10612) with the 1.3m PAIRITEL located at
Mt. Hopkins, Arizona for a second epoch beginning at 2010-04-20 07:59
UT, ~34.8 hours after the Swift trigger. In mosaics (effective
exposure time of 1.27 hours) taken simultaneously in the J, H, and Ks
filters, we observe that the afterglow has faded approximately 1
magnitude since our first epoch (Klein et al., GCN 10627).
Unfortunately, poor weather conditions prevented further observations
on 2010-04-21 and 2010-04-22.
The preliminary photometry yields:
post burst
t_mid (hr) exp.(hr) filt mag m_err
35.81 1.27 J 18.0 0.1
35.81 1.27 H 17.2 0.1
35.81 1.27 Ks 16.3 0.1
All magnitudes are given in the Vega system, calibrated to 2MASS. No
correction for Galactic extinction has been made to the above reported
values.