  A star destroyed by a supermassive black hole (SMBH) in a tidal disruption
event (TDE) enables the study of SMBHs. We propose that the distance within
which a star is completely destroyed by a SMBH, defined $r_{\rm t, c}$, is
accurately estimated by equating the SMBH tidal field (including numerical
factors) to the maximum gravitational field in the star. We demonstrate that
this definition accurately reproduces the critical $\beta_{\rm c} = r_{\rm
t}/r_{\rm t, c}$, where $r_{\rm t} =
R_{\star}\left(M_{\bullet}/M_{\star}\right)^{1/3}$ is the standard tidal radius
with $R_{\star}$ and $M_{\star}$ the stellar radius and mass and $M_{\bullet}$
the SMBH mass, for multiple stellar progenitors at various ages, and can be
reasonably approximated by $\beta_{\rm c} \simeq \left[\rho_{\rm
c}/(4\rho_{\star})\right]^{1/3}$, where $\rho_{\rm c}$ ($\rho_{\star}$) is the
central (average) stellar density. We also calculate the peak fallback rate and
time at which the fallback rate peaks, finding excellent agreement with
hydrodynamical simulations, and also suggest that the partial disruption radius
-- the distance at which any mass is successfully liberated from the star -- is
$\beta_{\rm partial} \simeq 4^{-1/3} \simeq 0.6$. For given stellar and SMBH
populations, this model yields, e.g., the fraction of partial TDEs, the peak
luminosity distribution of TDEs, and the number of directly captured stars.
