AstroNote 2023-296

AT 2023wrk was reported to TNS by Godson et al. (TNS Astronomical Transient Report No. 192729) based on observations with GOTO-N_GOTO-2 (GOTO23bdo) on UT 2023-11-04 05:29:46 at L-GOTO = 18.11 +/- 0.07. The last non detection by GOTO was on UT 2023-11-02 05:39:22 with an L-GOTO limiting magnitude of 18.5.

Li et al. (TNS Classification Report No. 15965) reported to TNS the spectroscopic classification of SN 2023wrk as a young SN Ia using the Lijiang-2.4m telescope and YFOSC. They initially reported a SN redshift of z = 0.023 and corrected it to z = 0.01 in a second report toTNS. Our analysis of the spectrum of SN 2023wrk obtained by Li et al. using SNID and Next Generation Superfit gives good matches to several SNe Ia at about 10-15 days before maximum light at the redshift of the likely host galaxy NGC 3690 (z = 0.010411 +/- 0.000010, NED).

ZTF detections have been reported to TNS by Forster et al. (ZTF23abpbdfm, ALeRCE) with a first detection on UT 2023-11-05 11:12:04 at g-ZTF = 16.905 +/- 0.051. The last non detection by ZTF was on UT 2023-11-03 12:34:12 with a g-ZTF limiting magnitude of 19.667. Another detection has been reported by K. Nishimura, with mag 16 (Clear) on UT 2023-11-08 15:21:36.

Here, we report our independent discovery of SN 2023wrk (ULL-ASTRO-MASTER-7) with the Las Cumbres Observatory Planewave Delta Rho 350 telescope, equipped with a QHY600 CMOS camera, at the Las Cumbres Observatory node at McDonald Observatory, in a short (35 sec) observation in the SDSS r' filter on UT 2023-11-07 10:49:37 at r' = 16.12 +/- 0.08.

David Bishop noticed in his compilation of supernovae that SN 2023wrk is the 14th supernova in NGC 3690, and the first SN Ia in this galaxy. NGC 3690 (Arp 299) is a well-studied luminous infrared galaxy in a system of interacting galaxies.  SN  2023wrk is located at about one arcmin of the center of the interacting galaxies system and at 2.6 arcsec of a faint galaxy detected in the SDSS, PanSTARRS and DESI LS imaging surveys (SDSS J112839.31+583310.3), that might be a dwarf galaxy associated with NGC 3690.

We encourage follow-up observations.

The ZTF light curve of SN 2023wrk is available at the ZTF/LSST brokers, e.g.:

Lasair, ALeRCE, ANTARES, and Fink

Location of SN 2023wrk on the DESI Legacy Survey imaging

This work makes use of observations from the Las Cumbres Observatory global telescope network (program IAC2023B-001) and is based on observations made with the Las Cumbres Observatory’s education network telescopes that were upgraded through generous support from the Gordon and Betty Moore Foundation. These observations and analysis are part of a course in Astrophysical Techniques of the Master in Astrophysics of the Astrophysics Department of the University of La Laguna and the Instituto de Astrofísica de Canarias (Tenerife, Spain). We thank David Bishop for his very useful compilation of supernovae and for noticing the association of SN 2023wrk with NGC 3690.