Photoevaporation of Low-Mass Cores Near Massive Stars: Mass-Loss Rates and Survival Distances

This paper addresses a single question: At what distance from a young massive cluster can a solar-mass core survive long enough to form its star before ionising radiation boils its surface away? Using published molecular-cloud and young-stellar-object measurements as inputs, and carrying the spin-torsion density bound of 9.72 x 10^57 kilograms per cubic metre and its critical shear of 8.56 x 10^32 per second as fixed comparison scales, the calculation finds that the estimated photoevaporative mass-loss rate for a core one parsec from a cluster emitting 10^50 ionising photons per second is of order 10^-5 solar masses per year, giving a solar-mass core a survival time of a few tens of thousands of years, within a factor of a few of its collapse time - survival is marginal at one parsec, comfortable at three parsecs, and unlikely at three tenths of a parsec, which predicts a zone near massive clusters where low-mass star formation is truncated rather than triggered. The headline values are: mdot 1pc = 2.57e-05; t evap 1pc yr = 3.89e+04; mdot 03pc = 8.56e-05. All values are computed from the stated formulae and inputs; this is a simulated and computed study, not a measurement. Where the comparison scales supplied by the torsion framework turn out to be too remote to influence the process, that outcome is reported as a negative result rather than passed over.