TITLE: GCN CIRCULAR NUMBER: 24574 SUBJECT: LIGO-Virgo S190517h: AGILE GRID observations DATE: 19/05/17 09:17:52 GMT FROM: Francesco Verrecchia at ASDC F. Verrecchia (SSDC, and INAF-OAR), G. Piano (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Ursi (INAF/IAPS), F. Lucarelli, C. Pittori (SSDC, and INAF-OAR), M. Cardillo, C. Casentini, A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste), report on behalf of the AGILE Team: In response to the LIGO-Virgo GW event S190517h at T0 = 2019-05-17 05:51:01.83 UTC (GCN #24570 including an updated localization) a preliminary analysis of the AGILE exposure at T0 showed that the S190517h 90% c.l. localization region (LR) was not exposed by the Gamma-Ray Imaging Detector (GRID). We performed an analysis of the GRID data in the energy range 50 MeV - 10 GeV over two time intervals before and after T0, where good exposure of the S190517h 90% c.l. LR was available. No candidate gamma-ray transient was detected. The following preliminary GRID 3-sigma upper limit (UL) values are obtained: (T0-100s; T0 ): from 1.9e-07 to 7.9e-07 erg cm^-2 s^-1, with exposure of about 60% of the LR; (T0+200s; T0 + 300s): from 4.5e-08 to 6.5e-07 erg cm^-2 s^-1, with exposure of about 50% of the LR. These measurements were obtained with AGILE observing a large portion of the sky in spinning mode. Additional analysis of AGILE data is in progress.