[2] SN 2022jli was discovered by astronomer Libert Monard [it] at Kleinkaroo Observatory, who reported it to the Transient Name Server (TNS) on May 5, 2022, as AT 2022jli.
This repeating pattern of oscillations is observed across multiple filters and instruments over many cycles, the first unambiguous detection of periodicity in a supernova light curve.
The total rise time to maximum brightness is ≥59 days, much longer than typical for stripped-envelope core-collapse supernovae.
Spectra show features typical of Type Ic supernovae, with iron, calcium and sodium P Cygni profiles.
The source of the early excess and periodic oscillations is uncertain, but plausible explanations include interaction of the ejecta with circumstellar material or a binary companion star.