[vsnet-grb-info 25295] LIGO/Virgo S200316bj: upper limits from AGILE/MCAL observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27395
SUBJECT: LIGO/Virgo S200316bj: upper limits from AGILE/MCAL observations
DATE:    20/03/17 05:06:19 GMT
FROM:    Maura Pillia at INAF  <maura.pilia at inaf.it>

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

In response to the LIGO/Virgo GW event S200316bj at T0 = 2020-03-16
21:57:56.157 (UT), a preliminary analysis of the AGILE minicalorimeter
(MCAL) triggered data found no event  candidates within a time interval
covering -/+ 15 sec from the LIGO/Virgo T0.

At the T0, about 50% of the S200316bj 90% c.l. localization region was
accessible to the AGILE MCAL.

Three-sigma upper limits (ULs) are obtained for a 1 s integration time at
different celestial positions within the accessible S200316bj localization
region, from a minimum of 1.1E-06 erg cm^-2 to a maximum of 2.1E-06 erg
cm^-2 (assuming as spectral model a single power-law with photon index 1.5).

An independent procedure based on photon counting statistics provides UL
fluences in the range 0.4-1 MeV, for a 300 us integration time, from a
minimum of 1.0E-08 erg cm^-2 to a maximum of 2.1E-08 erg cm^-2.

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.