TITLE: GCN CIRCULAR NUMBER: 25209 SUBJECT: LIGO/Virgo S190728q: Classification of AT2019lvs/ZTF19abjethn as a CV DATE: 19/07/28 22:01:16 GMT FROM: Kate Maguire at Trinity College Dublin Mark Magee (TCD), Kate Maguire (TCD), Manuel Torres (IAC), Peter Jonker (SRON/Radboud University), Morgan Fraser (UCD) report on behalf of the GW@WHT collaboration: We obtained an optical spectrum of the transient AT2019lvs/ZTF19abjethn discovered by ZTF (Kasliwal et al. GCN 25199) within the original probability map of S190728q (GCN 25187) but not the updated one released in GCN/LVC NOTICE on Sun 28 Jul 19 20:29:15 UT (see also GCN 25207). The spectrum was obtained on 2019 July 28 21:40 UT using the ACAM instrument mounted on the William Herschel Telescope located on the Roque de Los Muchachos Observatory, La Palma, Spain. The spectrum shows Balmer series emission at z=0 consistent with a cataclysmic variable.