Shock Cooling and Possible Precursor Emission in the Early Light Curve of the Type II SN 2023ixf

Understand

We present the densely sampled early light curve of the Type II supernova (SN) 2023ixf, first observed within hours of explosion in the nearby Pinwheel Galaxy (Messier 101; 6.7 Mpc).

• Comparing these data to recently updated models of shock-cooling emission, we find that the progenitor likely had a radius of $410 \pm 10\ R_\odot$.
• Our estimate is model dependent but consistent with a red supergiant.
• These models provide a good fit to the data starting about 1 day after the explosion, despite the fact that the classification spectrum shows signatures of circumstellar material around SN 2023ixf during that time.