GCN Circular 24419
Phil Evans (U. Leicester) and F.E. Marshall (NASA/GSFC) report on behalf of the Swift team: Swift-XRT has performed follow-up observations of the AGILE-detected burst GRB 190501A (Ursi et al. GCN Circ. 24360), collecting 2.9 ks of Photon Counting (PC) mode data between T0+146.7 ks and T0+157.7 ks. The XRT field-of-view covers about 7% of the AGILE/GRID 95%-confidence error region (Verrecchia et al. GCN Circ. 24363) and none of the IPN 3-sigma error region (Hurley et al. GCN Circ. 24732). No uncatalogued X-ray sources have been detected. The 3-sigma upper limit in the field ranges from ~0.003 to ~0.004 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.2e-13 to 1.7e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum). Three previously-catalogued X-ray sources have been detected, however their status as catalogued objects makes them unlikely to be the afterglow. The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/ToO_GRBs/00020892. The Swift/UVOT began settled observations of the field of GRB 190501A 146672 s after the AGILE trigger. No optical afterglow consistent with the AGILE/GRID position is detected in the initial UVOT exposures. The UVOT images cover about 4% of the 95%-confidence AGILE/GRID error region and none of the IPN 3-sigma error region. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 147234 153893 933 >21.8 v 147796 154103 761 >20.0 u 146672 157636 1167 >20.7 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998). This circular is an official product of the Swift team.