Color-singlet strangelets at finite temperature

Considering massless $u$ and $d$ quarks, and massive $s$ quarks confined in a bag with the bag pressure constant $B^{1/4}=145\mathrm{}$ MeV, a grand canonical partition function with color-singlet restriction [singlet of SU(3) color gauge group] is constructed at finite temperature. Then the stability of finite size strangelets with the baryon number $A<~100$ is studied minimizing the free energy as a function of the radius of the bag. As expected, the color singletness has effects only at finite temperatures and its importance grows with the increase of temperature. Notably, the most pronounced shell structure (metastable state) at $A$=6 now vanishes only at $T>~$30 MeV as compared to $T$=20 MeV otherwise. The color-singletness restriction has significant effects on the structure of low mass $(A$≲$50)$ strangelets but becomes unimportant in the bulk limit.