Erik Rosolowsky edited Table_ref_tab_masses_shows__.tex  almost 8 years ago

Commit id: 7d8c6ed9565db38effee19d54a229aea958507cd

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\begin{equation}  M_{c,\mathrm{cluster}} = \epsilon \Gamma M_{c,\mathrm{GMC}},  \end{equation}  where $\epsilon$ is the star formation efficiency (dimensionless) and $\Gamma$ is the bound cluster formation efficiency. The cluster formation efficiency has been observed in M83 to decrease with radius \citep{Silva_Villa_2013} with typical values of $\sim$10\%. Star formation efficiencies of molecular clouds are $\sim 10\%$, consistent with cloud lifetimes of $\sim 30$ Myr \citep{Fukui_2010, Meidt_2015}, star formation per free fall time of $\epsilon_{\mathrm{ff}} = 10^{-2}$ \citep{Krumholz_2011}, and free fall times of 3 Myr (Table \ref{tab:masses}). Combining these two efficiencies suggests the observed values of $M_{c,\mathrm{cluster}}/ M_{c,\mathrm{GMC}} = 10^{-2}$ is largely consistent with expectations. For $R_g>0.5$~kpc, $R_{\mathrm{gal}}>0.5$~kpc,  the observed cluster formation efficiency $\Gamma$ drops by a factor 3 over the region studied \citep{Silva_Villa_2013}, but the internal conditions of the molecular clouds do not change significantly in the disk of the galaxy. The clouds all show roughly constant properties including turbulence, surface density, internal pressure and free-fall time (Figure \ref{fig:radial}, Table \ref{tab:masses}).