[vsnet-grb-info 23399] LIGO/Virgo S190828j: No counterpart candidates in AGILE-MCAL observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25498
SUBJECT: LIGO/Virgo S190828j: No counterpart candidates in AGILE-MCAL observations
DATE:    19/08/28 07:49:25 GMT
FROM:    Francesco Longo at U of Trieste,INFN Trieste  <franzlongo1969 at gmail.com>

F. Longo (Univ. Trieste, and INFN Trieste), C. Pittori, F. Verrecchia
(SSDC, and

INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo,

C. Casentini, G. Piano, A. Ursi (INAF/IAPS), F. Lucarelli (SSDC, and
INAF/OAR),

A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia

(INAF/OA-Cagliari), report on behalf of the AGILE Team:


In response to the LIGO/Virgo GW event S190828j at T0 = 2019-08-28
06:34:05.756 (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 40% of the S190828j 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
S190828j

localization region, from a minimum of 1.55E-06 erg cm^-2 to a maximum of

7.31E-06 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.