TITLE: GCN CIRCULAR NUMBER: 25630 SUBJECT: LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations DATE: 19/09/03 14:32:13 GMT FROM: Martina Cardillo at INAF-IAPS M. Cardillo (INAF/IAPS), F. Verrecchia (SSDC,and INAF/OAR), F. Longo (Univ. Trieste, and INFN Trieste),C. Pittori, F. Lucarelli (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS and Univ. Roma Tor Vergata),C. Casentini, G. Piano, A. Ursi (INAF/IAPS),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 S190901ap at T0 = 2019-09-01 23:31:01.838 UTC a preliminary analysis of the AGILE exposure at T0 shows that the Gamma-Ray Imaging Detector (GRID) exposure covered about 20% of the 90% c.l. localization region (LR) (13% of 90% c.l. localization region (LR) is occulted by Earth). We performed an analysis of the GRID data in the energy range 50 MeV - 10 GeV on T0, where good exposure of the S190901ap 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 obtained: from 3.00e-07 to 9.32e-06 erg cm^-2 s^-1, with exposure of about 16% of the LR over the time interval ( T0s ; T0 + 10s ); from 3.59e-08 to 6.91e-06 erg cm^-2 s^-1, with exposure of about 26% of the LR over the time interval ( T0s ; T0 + 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.