GCN Circular 1160
K. Z. Stanek (Harvard-Smithsonian CfA) and L. Wyrzykowski (Warsaw University Observatory) report: Additional R-band observations of the GRB011121 OT carried out with the OGLE 1.3m telescope indicate continuing fading behavior of the afterglow (GCNs 1151, 1152, 1154): HJD-2450000 UT R_c exp 2237.8276 011124 07:47 21.97+-0.07 6x900 sec The R-band magnitudes are relative to star "A" of Wyrzykowski et al. (GCN 1150), which we now take to be R=18.2 after correction by 0.8 mag determined by Olsen et al. (GCN 1157) and Brown et al. (GCN 1158). This measurement might be fairly significantly contaminated by the possible host galaxy. It was derived with DaoPhot/Allstar PSF-fitting software (Stetson 1992), which near the OT finds another source located about 0.8"S and 1.8"E (see deep finding chart and PSF-fitting residua at http://cfa-www.harvard.edu/cfa/oir/Research/GRB/) with magnitude R=21.91+-0.07. We also correct our previous measurements by 0.8 mag: HJD-2450000 UT R_c exp 2235.71890 011122 05:19 19.11+-0.03 200 sec 2235.80322 011122 07:20 19.44+-0.03 200 sec 2235.85176 011122 08:30 19.60+-0.03 600 sec 2236.71036 011123 05:06 21.15+-0.07 3x600 sec Further, deep observations of the OT are strongly encouraged. We designate fainter comparison star "C" (see the WWW finding chart), which by comparison to "A" we measure to be R=20.09+-0.02 (statistical error only, no color term correction included). This message can be cited.