TITLE: GCN CIRCULAR NUMBER: 36502 SUBJECT: GRB 240516A: Swift-XRT refined Analysis DATE: 24/05/17 06:58:50 GMT FROM: Phil Evans at U of Leicester <pae9@star.le.ac.uk> K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team: We have analysed 6.7 ks of XRT data for GRB 240516A. Following the prompt detection of an X-ray source reported in GCN Circ. 36493 (Parsotan et al.), Swift passed into the South Atlantic Anomaly, and so no further data were collected until 1.6 ks after the BAT trigger. Combining all the Photon Counting (PC) mode data collected after this time (6.7 ks, from 1.6 to 45.5 ks post-trigger), the source is no longer detected, with a 3-sigma upper limit of 2.2 x 10^-3 count s^-1. Assuming a typical GRB spectrum with a photon spectral index of 1.9 and the Galactic absorption column of 1.29 x 10^22 cm^-2 (Willingale et al. 2013), the counts to observed (unabsorbed) 0.3-10 keV flux conversion deduced from this spectrum is 5.6 x 10^-11 (1.0 x 10^-10) erg cm^-2 count^-1. The observed (unabsorbed) flux upper limit for the X-ray source is thus 1.2 x 10^-13 (2.2 x 10^-13) erg cm^-2 s^-1. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/36502. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...