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

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.