[vsnet-grb-info 22146] LIGO-Virgo S190426c: AGILE MCAL observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24245
SUBJECT: LIGO-Virgo S190426c: AGILE MCAL observation
DATE:    19/04/26 18:52:06 GMT
FROM:    Martina Cardillo at INAF-IAPS  <martina.cardillo at inaf.it>

M.Cardillo , G.Piano, A. Ursi (INAF/IAPS), F. Verrecchia  (SSDC, and 
INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), C. 
Casentini, (INAF/IAPS), F. Lucarelli, C. Pittori,  (SSDC, and INAF/OAR), 
A. Bulgarelli, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia 
(INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste), report 
on behalf of the AGILE Team:

In response to the LIGO-Virgo GW event S190426c at T0 = 
2019-04-26T15:21:55.337 (UT), a preliminary analysis of the AGILE 
minicalorimeter (MCAL)  data found no event candidates within a time 
interval covering +/- 100 sec from the LIGO-Virgo T0.

Three-sigma upper limits (ULs) are obtained for a 1 s integration time 
at different celestial positions within the accessible S190426c  90% 
c.l. localization region (that one which includes the Celestial North 
Pole),  from a minimum of 1.27e-6 erg cm^-2 to a maximum of 2.16e-6 erg 
cm^-2  (assuming as spectral model a single power law with photon index 
1.5).

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in 
the energy range 0.4-100 MeV. Additional analysis of AGILE data is in 
progress.