Accreted mass required for TNR as a function of white dwarf mass, assuming a critical pressure of P_crit = 10²⁰ dyn cm⁻² and the mass–radius relations of Eggleton, as reported in Truran & Livio (1986) and Althaus et al. (2005). The dependence of the latter on stellar effective temperature is also illustrated, while the grayscale segment shows its linear extrapolation to higher masses. The upper limit to the total ejected mass adopted here is indicated by the lower shaded region.