TITLE: GCN CIRCULAR NUMBER: 13715 SUBJECT: XMM observations of the short GRB120804A DATE: 12/09/05 19:53:38 GMT FROM: Raffaella Margutti at Harvard R. Margutti (Harvard), V. Mangano (INAF IASF-Palermo), E. Berger, and W. Fong (Harvard) report: "We observed the short GRB120804A (GCN 13573) with XMM-Newton starting on 2012 August 22, 21:51:29 UT (18.8 days after the burst). GRB120804A is clearly detected at a level of 6 sigma with count-rate of (4.3 +\- 0.7)e-3 cps (0.2-10 keV) in the pn. The pn net exposure time is 25.5 ks. Using our best estimate of the intrinsic neutral hydrogen absorption (NH_int=3.2e21 cm-2) and the Galactic absorption in the direction of the burst (NH_gal=9.3e20 cm-2, Kalberla et al., 2005), this translates into an unabsorbed 0.3-10 keV flux of 2.4e-14 erg/s/cm2. Our analysis does not support the presence of a jet break for t< 18.8 days. Combining the Swift-XRT (GCN 13580), Chandra (GCN 13640, 13643) and XMM observations, for t>10^4 s the X-ray afterglow of GRB120804A is best modeled by a simple power-law decay with index=1.0 +\- 0.1. We thank the XMM-Newton staff for approving this observation."