Optical phot. and sp. monitoring of SN 2019esa

Early, high-cadence light curves from both TESS and the DLT40 survey tightly constrain the time of explosion, and show a 30 day rise to maximum light followed by a near-constant linear decline in luminosity.

Optical spectroscopy over the first 40 days revealed a reddened object with narrow Balmer emission lines seen in Type IIn SNe. The slow rise to maximum in the optical light curve combined with the lack of broad H{alpha} emission suggest the presence of very optically thick and close circumstellar material (CSM) that quickly decelerated the SN ejecta. This CSM was likely created from a massive star progenitor with an dM/dt~0.2M_{sun}_/yr lost in a previous eruptive episode 3-4yr before eruption, similar to giant eruptions of luminous blue variable stars.