TAPIR Seminar

In person: 370 Cahill. To Join via Zoom: 864 8902 5566

ABSTRACT: Stripped-envelope supernovae (SESNe) are a subclass of core-collapse supernovae that have lost some or all of their outer layers prior to collapse. The progenitors of these events likely lose their hydrogen (SNIIb, SNIb) and possibly helium (SNIc) layers through a combination of stellar winds and interactions with a close binary companion. However, the characteristic ejecta mass ranges covered by each subtype and how they relate to the progenitors' zero-age main-sequence masses remain unclear. Using a combination of semi-analytic modeling and numerical simulations, we can explore how the properties of SESN progenitors can be constrained through different phases of the bolometric light curve and see that early phases are strongly impacted by the treatments of nickel mixing and helium recombination. We are motivated to avoid uncertainties related to these treatments and instead focus on calibrating the relationship between the ejecta mass, explosion energy, and the late time slope of the light curve, which is determined by gamma-ray leakage. As the sample of SESNe late time data grows, our methods can be utilized to better understand the diversity of their progenitor stars.