GCN Circular 14922
W. Fong, G. Migliori, R. Margutti, and E. Berger (Harvard) report: "We observed the short-duration GRB 130603B (Melandri et al., GCN 14735) with XMM-Newton + EPIC-pn starting on 2013 June 06.22 UT (2.57 d after the burst) for a total of 24 ksec. We clearly detect the X-ray afterglow at the position of the enhanced XRT error circle (Evans et al., GCN 14739) at a significance level of about 6-sigma. Taken together with the Swift/XRT afterglow light curve for t>4000 sec (Kennea et al., GCN 14749), these observations indicate a single power-law decline with index alpha_X=-1.83+/-0.15. Therefore, the XMM observations rule out the presence of a break at t~4000 sec to 2.57 d, in contrast to the suggested X-ray and optical break at ~8 hr (Tanvir et al., arXiv: 1306.4971)."