[vsnet-grb-info 10472] GRB 110406A: Positional coincidence with NGC 404

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11909
SUBJECT: GRB 110406A: Positional coincidence with NGC 404
DATE:    11/04/08 15:43:53 GMT
FROM:    Antonia Rowlinson at U.of Leicester  <bar7 at star.le.ac.uk>

A. Rowlinson, P.T. O'Brien, N.R. Tanvir (U. Leicester) and A.J. Levan
(U. Warwick) report:

We note that the the error box of the bright short hard GRB 110406A
detected by INTEGRAL SPI-ACS and the IPN (GCNs 11890, 11893, 11900)
overlies NGC 404, a dwarf galaxy at a distance of ~3 Mpc. The IPN
error box and the extent of NGC 404 are overlayed on a GALEX FUV image
here: http://www.star.le.ac.uk/~bar7/NGC404_FUV.jpg

NGC 404 is a recently rejuvinated lenticular galaxy, forming the
majority of its new stars in a ring with a star formation rate of
2.5e-3 M_sol yr^-1 (Thilker et al., 2010, ApJ, 714, L171).

If this GRB is associated with NGC 404, the isotropic energy released
would be ~6e46 erg (20 keV - 10 MeV) using the Konus-Wind spectral fit
(GCN 11893) which would be consistent with an SGR giant flare origin,
while the presence of a young stellar population within this galaxy
would also be consistent with this model. For comparison, the giant
flare from SGR 1806-20 had Eiso ~3.7e46 erg (Hurley et al., 2005,
Nature, 434, 1098).