Cannibal-sector temperature ratio ($T_{\gamma }/T_{\varphi }$)

For a massive real scalar with one internal degree of freedom with $x=m/T_{\varphi }\gg 1$, fixed separately conserved visible and dark entropy ratio $\xi$, and relativistic visible bath with entropy degrees of freedom $g_{\ast s}^{\mathrm{SM}}$,Indeed, equate $s_{\mathrm{SM}}=(2{\pi }^2/45)g_{\ast s}^{\mathrm{SM}}{T}_{\gamma }^3$ to $\xi s_{\varphi }$ and use nonrelativistic entropy at zero chemical potential. For $g$ internal states the right side gains $g^{1/3}$. The nonrelativistic species cannot be assigned a constant relativistic entropy count.