Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 26448

LIGO/Virgo S191215w: upper limits from AGILE-GRID observations
2019-12-16T09:09:55Z (4 years ago)
Francesco Verrecchia at ASDC <>
F. Verrecchia (SSDC, and INAF/OAR), M. Pilia (INAF/OA-Cagliari),
M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo,
C. Casentini, G. Piano, A. Ursi (INAF/IAPS), F. Lucarelli, C. Pittori
(SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, 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 S191215w at T0 = 2019-12-15
22:30:52.333 UTC a preliminary analysis of the AGILE exposure at T0
shows that the Gamma-Ray Imaging Detector (GRID) exposure covered less
than 10% of the 90% c.l. localization region (LR) (35% of 90% c.l. LR
is occulted by Earth).

We performed an analysis of the GRID data in the energy range 50 MeV -
10 GeV over time intervals before and after T0, where good exposure of
the S191215w 90% c.l. LR was available.

No candidate gamma-ray transient was detected.

The following preliminary GRID values of 3-sigma upper limit (UL) are

from 2.0e-07 to 9.4e-07 erg cm^-2 s^-1, with exposure of about 45% of
the LR over the time interval ( T0 + 100s ; T0 + 200s );

These measurements were obtained with AGILE observing a large portion
of the sky in spinning mode. Additional analysis of AGILE data is in
Looking for U.S. government information and services? Visit