AstroNote 2024-111

The Zwicky Transient Facility (ZTF; Bellm et al. 2019; Graham et al. 2019) Superluminous Supernova Science Program (Lunnan et al. 2020; Yan et al. 2020; Chen et al. 2023a,b) reports 9 candidate SLSNe, following the methodology outlined by Perley et al. (in prep.). We selected transients that have a long rise time (>20 days) and a faint host galaxy.

We summarise properties of the candidates in the Related Objects Table. These include coordinates, current magnitudes, approximate rise times, photometric redshifts of potential host galaxies (taken from the SDSS DR14 and Legacy Survey DR9) and special remarks.

We will distribute alerts on such SLSN candidates via AstroNotes periodically; spectroscopic classifications and additional follow-up observations of these transients are encouraged.

This report is based on photometric observations obtained with the Samuel Oschin Telescope 48-inch at the Palomar Observatory as part of the Zwicky Transient Facility project, and from the Liverpool Telescope Infrared-Optical:Optical (IO:O) imager. We also obtained spectra for 4 events using the Alhambra Faint Object Spectrograph and Camera (ALFOSC) on the Nordic Optical Telescope (NOT), the Double Spectrograph (DBSP) on the Palomar P200 telescope, and the Spectral Energy Distribution Machine (SEDM) on the Palomar 60-inch telescope.

ZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Oskar Klein Center at Stockholm University, the University of Maryland, University of California, Berkeley , the University of Wisconsin at Milwaukee, University of Warwick, Ruhr University, Cornell University, Northwestern University and Drexel University. Operations are conducted by COO, IPAC, and UW.