Pressure-confined Jeans mass
= Pressure-confined Jeans mass
{title2=$M_J\propto v^4/(G^{3/2}P^{1/2})$}
For a cloud supported by an effective <speed of sound> $v$ and confined by a surface <pressure> $P$, <dimensional analysis> fixes the <gravitational instability> mass scale to $v^4/(G^{3/2}P^{1/2})$. The dimensionless coefficient depends on the equilibrium model and the convention used for the instability threshold.