Radiation-to-gas pressure ratio
= Radiation-to-gas pressure ratio
{title2=$\beta_{\rm rg}=p_{\rm rad}/p_{\rm gas}$}
The radiation-to-gas pressure ratio compares <radiation pressure> with <gas pressure>. It is distinct from <plasma beta>, which compares gas pressure with <magnetic pressure>. Both are sometimes denoted by $\beta$, so the convention must be stated.