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GCN Circular 24356

LIGO/Virgo S190425z: ZTF pre-detections of Gaia19bpt AT2019ehz
2019-04-30T18:33:36Z (5 years ago)
Igor Andreoni at Caltech <>
Igor Andreoni (Caltech), Eric Bellm (UW) report on behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations


We searched for Zwicky Transient Facility (ZTF) detections associated with Gaia19bpt AT2019ehz (Kostrzewa-Rutkowska et al., GCN 24354) in the archive of ZTF alerts. ��A source, dubbed ZTF19aarioci, was found varying at the location of Gaia19bpt.�� The source was first detected in ZTF data on 2019-04-21 (g ~ 19.8), with detections in the public surveys beginning on 2019-04-23.


The optical event was detected days before the gravitational wave trigger S190425z (LIGO and Virgo Collaboration, GCN 24168), therefore we exclude an association between Gaia19bpt AT2019ehz and S190425z. 


ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IIT-B, India; IIA, India; LJMU, UK; TTU USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019).
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