How to solve the mass-discrepancy problem of SESNe -- I. Testing model approximations

TL;DR

This study systematically tests common analytical assumptions in modeling stripped-envelope supernovae to address the mass-discrepancy problem, analyzing light curves, gamma-ray leakage, and velocity definitions across 59 events.

Contribution

It critically evaluates and quantifies the impact of typical model approximations on ejecta mass estimates in SESNe, providing insights to improve modeling accuracy.

Findings

R-band light curves are not always reliable proxies for bolometric light curves.

Rise-time to maximum brightness often differs from the effective diffusion time-scale.

Gamma-ray and positron leakage significantly affect late-time light curve modeling.

Abstract

Here, we present a systematic study of 59 stripped-envelope supernovae (SESNe) (including Type IIb, Ib, Ic, and transitional events) to map a possible reason for the so-called mass-discrepancy problem. In this scenario, we assume the tension between the estimated ejected masses from early- and late-time light curves (LC) is due to approximations generally used in analytical models. First, we examine the assumption that the R-band light curve is indeed a good approximation of the bolometric light curve. Next, we test the generally used assumption that rise-time to maximum brightness is equal to the effective diffusion time-scale that can be used to derive the ejecta mass from the early LC. In addition, we analyze the effect of gamma-ray and positron-leakage, which play an important role in forming the shape of the tails of SESNe, and also can be crucial to gaining the ejecta masses from the late-time LC data. Finally, we consider the effect of the different definitions of velocity that are needed for the ejecta mass calculations.