Abstract
Although Chandrasekhar-mass white dwarfs (WDs) accreting mass from non-degenerate stellar companions through the single-degenerate channel have reigned for decades as the leading explanation of SNe Ia, a comprehensive theoretical explanation has not yet emerged to explain the expected properties of the canonical near-Chandrasekhar-mass WD model. A simmering phase within the convective core of the WD leads to the ignition of one or more flame bubbles scattered across the core. Consequently, near-Chandrasekhar-mass single-degenerate SNe Ia are inherently stochastic and are expected to lead to a range of outcomes, from subluminous SN 2002cx-like events to overluminous SN 1991T-like events. However, all of the prior simulations of the single-degenerate channel carried through the detonation phase have set the ignition points as free parameters. In this work, for the first time, we place a single ignition point as predicted by ab initio models of the convective phase leading up to ignition and follow through the detonation phase in fully three-dimensional simulations. Single-degenerates in this framework are characteristically overluminous. Using a statistical approach, we determine the Ni-56 mass distribution arising from stochastic ignition. While there is a total spread of greater than or similar to 0.2 M-circle dot for detonating models, the distribution is strongly left-skewed and with a narrow standard deviation of similar or equal to 0.03 M-circle dot. Conversely, if single-degenerates are not overluminous but primarily yield normal or failed events, then our models require finetuning of the ignition parameters, or otherwise require revised physics or WD models. We also discuss the implications of our findings for the modeling of single-degenerate SNe Ia.