Caltech Core-Collapse Project (CCCP) Observations of Type II Supernovae: Evidence for Three Distinct Photometric Subtypes

TL;DR

This study analyzes Type II supernovae light curves from the CCCP, identifying three distinct photometric subtypes and suggesting different progenitor systems, with implications for understanding supernova origins.

Contribution

The paper classifies Type II supernova light curves into three distinct subtypes and links them to different progenitor systems, highlighting the potential binary origin of some stripped supernovae.

Findings

Most light curves fall into three classes: plateau, slowly declining, rapidly declining.

Type IIb SNe have light curves similar to SNe Ib, indicating possible similar progenitors.

Plateau durations are roughly 100 days, with a wide range of luminosities.

Abstract

We present R-Band light curves of Type II supernovae (SNe) from the Caltech Core Collapse Project (CCCP). With the exception of interacting (Type IIn) SNe and rare events with long rise times, we find that most light curve shapes belong to one of three distinct classes: plateau, slowly declining and rapidly declining events. The last class is composed solely of Type IIb SNe which present similar light curve shapes to those of SNe Ib, suggesting, perhaps, similar progenitor channels. We do not find any intermediate light curves, implying that these subclasses are unlikely to reflect variance of continuous parameters, but rather might result from physically distinct progenitor systems, strengthening the suggestion of a binary origin for at least some stripped SNe. We find a large plateau luminosity range for SNe IIP, while the plateau lengths seem rather uniform at approximately 100 days. As analysis of additional CCCP data goes on and larger samples are collected, demographic studies of core collapse SNe will likely continue to provide new constraints on progenitor scenarios.