TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4857 SUBJECT: GRB 060306: SOAR Ks Observations DATE: 06/03/10 20:39:30 GMT FROM: Melissa Nysewander at UNC,Chapel Hill M. Nysewander, D. Reichart, A. Oliveira, P. Ugarte, and A. Alvarez report on behalf of the UNC team of the FUN GRB collaboration: We observed the localization of GRB 060306 (Angelini et al., GCN 4848) with the SOAR infrared imager, OSIRIS, beginning at 00:31:56 UT on March 7th, 1.0 days after the burst. We detect no new source down to a 3-sigma limiting magnitude of Ks = 18.2 based on six stars from the 2MASS catalogue. If one assumes minimal extinction in the Ks band and uses the extrapolated to 24 hours, unabsorbed X-ray flux of Page et al. (GCN 4850), this suggests a NIR to X-ray spectral index that is shallower than -0.7. The source in the XRT error circle which is also in the DSS-Red plate (as noted by Price et al., GCN 4854) is at Ks = 17.3 +/- 0.2 mag. SOAR is currently being commissioned.