TITLE: GCN CIRCULAR NUMBER: 20817 SUBJECT: LIGO/Virgo G275697: P200/DBSP Classification of iPTF Candidates DATE: 17/03/05 07:23:39 GMT FROM: Mansi M. Kasliwal at Caltech K. De, N. Blagorodnova, R. Lunnan, M. Balokovic, N. Kamraj, M. Heida, D. Stern and M. M. Kasliwal (Caltech) report on behalf of the iPTF (intermediate Palomar Transient Factory) and GROWTH (Global Relay of Observatories Watching Transients Happen) collaborations On UT 2017-03-04, we spectroscopically classified the following optical transient candidates (LVC GCN#20802, LVC GCN#20791) using the Double Beam Spectrograph (Oke & Gunn 1982) on the Palomar 200-inch Hale Telescope. All spectra were reduced using the pyraf-dbsp pipeline (Bellm & Sesar 2016). Classification were done with SNID (Blondin & Tonry, 2007) and Superfit (Howell et al. 2005). Name, Redshift, Classification, Notes iPTF17bue, z=0.02, SN Ia, Best match is SN2005cf at +4d iPTF17buo, z=0, CV, Consistent with LVC GCN#20815 iPTF17bti, z=0, CV iPTF17bxa, z=0.076, Spectrum dominated by galaxy light iPTF17bub, z=0, M-dwarf flare iPTF17btx, z=0.022, SN II, just outside 90% contour line iPTF17bvw, z=0.132, SN Ia, Best match is SN2003du +0d iPTF17bvd, Unknown, Blue Featureless Spectrum iPTF17bva, z=0.112, SN Ia, Best match is SN1990N at -7d, just outside 90% contour line