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Hypervelocity stars (HVS) are a class of stars moving at high enoughvelocities to be gravitationally unbound from the Galaxy. Ejection from a closebinary system in which one of the components undergoes a thermonuclearsupernova (SN) has emerged as a promising candidate production mechanism forthe least massive specimens of this class. This study presents a thoroughtheoretical analysis of candidate progenitor systems of thermonuclear SNe inthe single degenerate helium donor scenario in the relevant parameter spaceleading to the ejection of HVS. The primary goal is investigation of the,previously unclear, characteristics of the velocity spectra of the ejectedcomponent. Presented are the results of 390 binary model sequences computedwith the MESA framework, investigating the evolution of supernova progenitorscomposed of a helium-rich hot subdwarf and a accreting white dwarf. Results arethen correlated with an idealized kinematic analysis of the observed object US708. It is seen that the ejection velocity spectra reach a maximum in the range$0.19~M_\odot < M_{HVS} < 0.25~M_\odot$. Depending on the local Galacticpotential, all donors below $0.4~\text{M}_\odot$ are expected to become HVS.This channel is able to account for runaway velocities up to $\sim1150~\text{kms}^{-1}$ with a Chandrasekhar mass accretor, exceeding $1200~\text{km s}^{-1}$if super-Chandrasekhar mass detonations are taken into account. It is foundthat the previously assumed mass of $0.3~M_\odot$ for US 708, combined withmore recently obtained proper motions, favor a sub-Chandrasekhar mass explosionwith a terminal WD mass between $1.1~M_\odot$ and $1.2~M_\odot$. The presenceof clear ejection velocity maxima provides constraints on the terminal state ofa supernova progenitor. It is possible to discern certain types of explosionmechanisms from the inferred ejection velocities alone.

Velocity limits in the thermonuclear supernova ejection scenario for hypervelocity stars and the origin of US 708