TITLE: GCN CIRCULAR NUMBER: 16034 SUBJECT: GRB 140323A: Fermi-LAT detection DATE: 14/03/24 09:54:39 GMT FROM: Elisabetta Bissaldi at U.Innsbruk/IAPP G. Vianello (Stanford), F. Longo and E. Bissaldi (University and INFN Trieste) report on behalf of the Fermi-LAT team: On March 23, 2014, Fermi-LAT detected high-energy emission from GRB 140323A, initially detected by Swift (Troja et al., GCN 16027) and also detected by Fermi-GBM (Yu et al., GCN 16032). We note that the GBM and the Swift trigger times are different. Here we will use as a reference the GBM trigger time, i.e. 10:22:53.12 UT. The data from the Fermi-LAT show a significant increase in the event rate within 10 degrees of the Swift location. More than 11 photons above 100 MeV and 3 photons above 1 GeV are observed within 1000 seconds from the GBM trigger time. The highest-energy photon is a 2.5 GeV event, which is observed ~220 seconds after the trigger. The best LAT on-ground location is found to be RA, Dec 356.46, -79.87 (J2000) with an error radius of 0.19 deg (90% containment, statistical error only). This is 0.09 deg from the Swift/XRT localization (GCN 16028) and is consistent with it. The source was 31 deg from the LAT boresight at the time of the trigger. The Fermi-LAT point of contact for this burst is Daniel Kocevski (daniel.kocevski@nasa.gov). The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.