A Semi-analytic Criterion for the Spontaneous Initiation of Carbon Detonations in White Dwarfs
arXiv:1701.08811 · doi:10.3847/1538-4357/aa5d58
Abstract
Despite over forty years of active research, the nature of the white dwarf progenitors of Type Ia supernovae remains unclear. However, in the last decade, various progenitor scenarios have highlighted the need for detonations to be the primary mechanism by which these white dwarfs are consumed, but it is unclear how these detonations are triggered. In this paper we study how detonations are spontaneously initiated due to temperature inhomogeneities, e.g., hotspots, in burning nuclear fuel in a simplified physical scenario. Following the earlier work by Zel'Dovich, we describe the physics of detonation initiation in terms of the comparison between the spontaneous wave speed and the Chapman-Jouguet speed. We develop an analytic expression for the spontaneous wave speed and utilize it to determine a semi-analytic criterion for the minimum size of a hotspot with a linear temperature gradient between a peak and base temperature for which detonations in burning carbon-oxygen material can occur. Our results suggest that spontaneous detonations may easily form under a diverse range of conditions, likely allowing a number of progenitor scenarios to initiate detonations that burn up the star.
arXiv comment9 pages, 3 figures, accepted to ApJ
References in corpus (24)
- Observational clues to the progenitors of Type-Ia supernovae
- Three-dimensional delayed-detonation models with nucleosynthesis for Type Ia supernovae
- Normal Type Ia supernovae from violent mergers of white dwarf binaries
- Detonations in Sub-Chandrasekhar Mass C+O White Dwarfs
- Three-dimensional pure deflagration models with nucleosynthesis and synthetic observables for Type Ia supernovae
- A Circumbinary Disk in the Final Stages of Common Envelope and the Core-Degenerate Scenario for Type Ia Supernovae
- Double-detonation supernovae of sub-Chandrasekhar mass white dwarfs
- The Thermonuclear Explosion Of Chandrasekhar Mass White Dwarfs
- Deflagration to Detonation Transition in Thermonuclear Supernovae
- Sub-Chandrasekhar White Dwarf Mergers as the Progenitors of Type Ia Supernovae
- The structure and fate of white dwarf merger remnants
- 2D simulations of the double-detonation model for thermonuclear transients from low-mass carbon-oxygen white dwarfs
- Carbon Ignition in Type Ia Supernovae: An Analytic Model
- The Initiation and Propagation of Helium Detonations in White Dwarf Envelopes
- Off-center ignition in type Ia supernova: I. Initial evolution and implications for delayed detonation
- On Type Ia Supernovae From The Collisions of Two White Dwarfs
- Spontaneous Initiation of Detonations in White Dwarf Environments: Determination of Critical Sizes
- Flame-driven deflagration-to-detonation transitions in Type Ia supernovae?
- Type Ia Supernova: Burning and Detonation in the Distributed Regime
- A Parameter-Space Study of Carbon-Oxygen White Dwarf Mergers
- Constraints On The Delayed Transition to Detonation in Type Ia Supernovae
- Local Ignition in Carbon/Oxygen White Dwarfs -- I: One-zone Ignition and Spherical Shock Ignition of Detonations
- A Subgrid-scale Model for Deflagration-to-Detonation Transitions in Type Ia Supernova Explosion Simulations - Numerical implementation
- Early Hydrodynamic Evolution of a Stellar Collision