[vsnet-grb-info 25497] GRB 200415A: Fermi-LAT localization update

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27597
SUBJECT: GRB 200415A: Fermi-LAT localization update
DATE:    20/04/16 20:48:00 GMT
FROM:    Nicola Omodei at Stanford U.  <nicola.omodei at slac.stanford.edu>

N. Omodei (Stanford University),  F. Piron (CNRS/IN2P3/LUPM), M. Axelsson (KTH & Stockholm Univ.), F. Longo (University and INFN, Trieste), D. Kocevski (NASA/MSFC), E. Bissaldi (Politecnico & INFN Bari)  and A. Berretta (University & INFN Perugia) 
report on behalf of the Fermi-LAT Collaboration:

We performed additional analysis to estimate the localization contour of GRB 200415A detected at high energy by Fermi-LAT (GCN 27586).
The best localization is at: R.A., Dec. = 11.07, -25.02 (degrees, J2000) with a circular error of 0.38 and 0.59 degrees (statistical only), respectively at 68% and 90% confidence levels.

The shape of the contour shows an elongation toward the location of the IPN error box (GCN 27595) placing the Sculptor Galaxy (NGC 253) between the 68% and the 90% c.l. contours. 
A localization map is posted at:
https://www-glast.stanford.edu/pub_data/1775/GRB200415A_TSMAP_LAT.gif

The Fermi-LAT point of contact for this burst is Alessandra Berretta (alessandra.berretta at pg.infn.it).

The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. 
It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.