AstroNote 2022-96

We note the rapidly-rising, potentially young supernova in a nearby galaxy. The object was first discovered by ALeRCE (2022TNSTR1085....1M) in ZTF g-band images obtained on April 27, 2022 at 04:55 UT, about 2 days after the last non-detection.  The object was picked up by a custom filter for infant SNe on the AMPEL broker system (Nordin et al. 2019). The object was saved by duty astronomers and rapid follow-up was triggered.

The first detection is 1.73 magnitudes above the most recent upper limit 1.86 days before. The object was detected with a blue color of g-r = -0.45 mag, and assuming the redshift of the host (UGC 06365, z=0.0108 from NED), was discovered around absolute magnitude Mg=-14.4 mag, suggesting that this potential SN is indeed <2 days old.

We triggered Swift/UVOT photometry and optical spectroscopy followup observations. The spectrum of the SN shows a blue continuum, indicating it is indeed a SN. The current brightness of the SN is g=19.1 mag, similar to the brightness one day beforehand. 

We will continue to distribute alerts on such early SN detections via AstroNotes; additional follow-up observations of this transient are highly encouraged.

ZTF is a project led by PI S. R. Kulkarni at Caltech, and includes IPAC; WIS, Israel; OKC, Sweden; JSI/UMd, USA; UW,USA; DESY, Germany; NRC, Taiwan; UW Milwaukee, USA and LANL USA. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. Alert distribution service provided by DIRAC@UW. Alert filtering is being undertaken by the GROWTH marshal system (Kasliwal et al. 2019), supported by NSF PIRE grant 1545949.