TITLE:   GCN CIRCULAR
NUMBER:  25152
SUBJECT: LIGO/Virgo S190718y: Classification of AT 2019lqn / Gaia19dct as a Type Ia Supernova
DATE:    19/07/25 17:14:27 GMT
FROM:    Iair Arcavi at Tel Aviv University  <arcavi@tauex.tau.ac.il>

Iair Arcavi (Tel Aviv University), Daichi Hiramatsu (Las Cumbres / UCSB), D. Andrew Howell (Las Cumbres / UCSB), Curtis McCully (Las Cumbres), Jamison Burke (Las Cumbres / UCSB), Craig Pellegrino (Las Cumbres / UCSB), on behalf of the Las Cumbres GW Follow-up Collaboration

We obtained an optical spectrum of the transient AT 2019lqn / Gaia19dct (discovered by Gaia within the probability map of S190718y; LIGO/Virgo Collaboration GCN 25087, Kostrzewa-Rutkowska et al. GCN 25145) on 2019 July 24.8 UT with the robotic FLOYDS instrument mounted on the Las Cumbres Observatory 2-meter telescope in Siding Spring, Australia.

Using Superfit (Howell et al. 2005, ApJ, 634, 1190) and SNID (Blondin & Tonry 2007, ApJ, 666, 1024) we find good fits to normal Type Ia supernovae at a redshift of z=0.076, and a phase of 9 days after peak. The spectrum is available on the <a href="http://wis-tns.weizmann.ac.il/object/2019lqn">Transient Name Server</a>.