Stellar lifetime regions in a mass-age diagram
= Stellar lifetime regions in a mass-age diagram
{title2=$\tau_a(M)<t<\tau_b(M)$}
A phase bounded by mass-dependent lifetimes $\tau_a(M)$ and $\tau_b(M)$ occupies $\tau_a(M)<t<\tau_b(M)$, clipped to the population age range. Its boundaries can be mapped into uniform <probability> coordinates to evaluate evolutionary-state fractions.