TITLE:   GCN CIRCULAR
NUMBER:  31897
SUBJECT: GRB 220412B: Swift-XRT observations
DATE:    22/04/13 18:27:35 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

V. D'Elia (SSDC & INAF-OAR), A. D'Ai (INAF-IASFPA), J. D. Gropp (PSU),
J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), K.L. Page (U.
Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB) and
J.D. Gropp (PSU) report on behalf of the Swift-XRT team:

We have analysed 7.8 ks of Photon Counting (PC) mode XRT data for the
Swift-BAT-detected burst GRB 220412B (Gropp et al. GCN Circ. 31886),
collected between T0+4.7 ks and T0+29.1 ks. 

No X-ray sources have been detected consistent with being within 296
arcsec of the Swift-BAT position. The 3-sigma upper limit in the field
is 0.001 ct  s^-1, corresponding to a 0.3-10 keV observed flux of
4.2e-14 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

Four uncatalogued sources were detected too far from the GRB position
to be likely afterglow candidates.

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/01102329.

This circular is an official product of the Swift-XRT team.