Tan, Krumholz & McKee (2006)

Abstract (paraphrased)¶

Argues that massive star clusters form in approximate dynamical equilibrium over several free-fall times, rather than in a single rapid free-fall collapse, with star formation proceeding at a low rate per free-fall time. In this picture the star-formation rate is set by applying a free-fall collapse kernel to the cloud’s characteristic (mean) density, integrated over the cluster-formation timescale.

Role in progenax (attribution — UNVERIFIED)¶

progenax’s gravoturbulence chapter cites this work as an earlier “single-mean-density” framework: it applies the same free-fall star-formation kernel ($\dot\rho_\star \propto \rho/t_{\rm ff} \propto \rho^{3/2}$) as the modern PDF-based treatments, but evaluated at a single mean density rather than integrated over a full density probability distribution. progenax uses it as the conceptual baseline against which the BM19 / Burkhart PDF-integrated magnification factor $\zeta$ is the improvement: integrating the same kernel over the lognormal+power-law density PDF (rather than a single mean) is what produces the geometric SFR boost.

Use in progenax¶

• Gravoturbulence — the equilibrium cluster-formation framework as context.

• The magnification factor ζ — three ways to compute it — cited as a single-mean-density baseline for the $\zeta$ magnification factor and the α↔p correspondence discussion.

• Density PDFs and the freefall-density factor — noted as the earlier framework that uses the same kernel without integrating over a density PDF.

Notes¶

The gravoturbulence subsystem is the experimental, repo-only gravoturb package (not in the released wheel). Until the PDF is held and verified, treat this note as a role/context summary rather than a confirmed transcription.