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GCN Circular 24106

LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
2019-04-12T14:24:33Z (5 years ago)
Zuzanna Kostrzewa-Rutkowska at SRON <>
Z. Kostrzewa-Rutkowska (SRON/RU), S. Hodgkin, A. Delgado, D.L. Harrison, M.
van Leeuwen, G. Rixon, A. Yoldas (IoA Cambridge), D. Eappachen, P.G. Jonker
(SRON/RU) on behalf of Gaia Alerts team report the discovery of a transient
candidate within the probability skymap of S190408an (Singer et al. GCN

Name      TNSid     Date [TCB]          RaDeg     DecDeg    AlertMag URL
Gaia19bhc AT2019ddt 2019-04-07 15:17:19 347.68061  47.16521 15.26

The transient was discovered by the MASTER survey on 2019-04-09.00417 UT
(MASTER OT J231043.63+470956.4; Lipunov et al. GCN 24084). However, the
transient was observed by Gaia one day before the LIGO/Virgo trigger
thereby re-enforcing the conclusion from Onori et al. (GCN 24090) and
Valeev et al. (GCN 24092) that it is unrelated to the GW event S190408an.

Acknowledgements: This work has made use of data from the European Space
Agency (ESA) mission Gaia (, processed by
the Gaia Data Processing and Analysis Consortium (DPAC, Funding for the DPAC
has been provided by national institutions, in particular the institutions
participating in the Gaia Multilateral Agreement. ZKR, DE, and PGJ
acknowledge support from the European Research Council under ERC
Consolidator Grant agreement no 647208.
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