TITLE:   GCN CIRCULAR
NUMBER:  21604
SUBJECT: LIGO/Virgo G298389: AGILE GRID observations
DATE:    17/08/19 22:10:50 GMT
FROM:    Francesco Verrecchia at ASDC, INAF-OAR  <verrecchia@asdc.asi.it>

G. Piano (INAF/IAPS), F. Verrecchia (SSDC and INAF/OAR), A. Bulgarelli
(INAF/IASF-Bo), M. Pilia (INAF/OA-Cagliari), M. Cardillo (INAF/IAPS), M.
Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), C. Pittori (SSDC and
INAF/OAR), I. Donnarumma (ASI), F. Longo (Univ. Trieste and INFN Trieste),
A. Ursi, G. Minervini, A. Argan, Y. Evangelista (INAF/IAPS), F. Lucarelli
(SSDC and INAF/OAR), N. Parmiggiani, A. Zoli, V. Fioretti, F. Fuschino
(INAF/IASF-Bo), A. Trois (INAF/OA-Cagliari) M. Marisaldi (INAF/IASF-Bo and
Bergen University), A. Giuliani (INAF/IASF-Mi), report on behalf of the AGILE
Team:

In response to the LIGO/Virgo GW trigger event G298389 at T0 = 2017-08-19
15:50:46.990 UTC (GCN #21600)  we performed an analysis of the AGILE Gamma-Ray
Imaging Detector
(GRID) data. At LIGO/Virgo trigger time (T0) the GRID exposure covered nearly
35% of the 90% c.l. LIGO/Virgo localization region (LR), observed at off-axis
angles between 45 and 70 deg.

An analysis of the data in the energy range 50 MeV - 10 GeV was performed
between -50 and +50 sec centered at T0.
Preliminary values of 3-sigma upper limits (UL) obtained within the accessible
LIGO/Virgo LR are:

from 6.0e-08 to 1.2e-06 erg cm^-2 s^-1 for integration time of 100s

These measurements were obtained with AGILE observing a large portion of the
sky in spinning mode. Additional analysis of AGILE data is in progress.