[vsnet-grb-info 4973] AGILE-ACS position for the SGR 1806-20 July 27 burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6688
SUBJECT: AGILE-ACS position for the SGR 1806-20 July 27 burst
DATE:    07/07/30 16:25:36 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro at iasf-milano.inaf.it>

F.Perotti, A.Giuliani, S.Mereghetti, M.Fiorini, S.Vercellone, A.Chen, 
A.Pellizzoni (IASF-Milano), C.Labanti, M.Trifoglio, G.Di Cocco 
(IASF-Bologna), M.Tavani, M.Feroci, A.Argan, A.Trois (IASF-Roma), 
G.Picozza (INFN-Roma), F.Longo, G. Barbiellini (INFN-Trieste), on behalf 
of the AGILE Team

and  P. Giommi, L.A. Antonelli, 
C. Pittori (ASDC), and L. Salotti (ASI) report:


The SGR-like burst detected on July 27 at about 06:41 UT with Konus/Wind, 
INTEGRAL-SPI-ACS, RHESSI and Suzaku-WAM (Golenetskii et al. GCN 6684), and 
likely associated to SGR 1806-20, has been seen also by the 
Anticoincidence system of AGILE.

This segmented anticoincidence detector surrounds the gamma-ray tracker 
on five sides (top and 4 lateral). The relative intensity of the count 
rates measured from the different sides allows to estimate the arrival 
direction of the detected bursts.

Based on a simple geometrical model, the detection of this event in two of 
the lateral panels and its non-detection in the top panel, yields an 
instrumental azimuthal angle within 3 degrees from that of SGR 1806-20.
 
We thus support the association of this event with SGR 1806-20.