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We have calculated $\beta^-$ decay rates to the continuum and bound states ofsome fully ionized atoms in the stellar s-process environment having freeelectron density and temperature in the range $n_e = 10^{26} $ cm$^{-3} -10^{27} $ cm$^{-3}$ and $T = 10^8$ K - $5 \times 10^{8}$ K, respectively. Thepresence of bare atoms in these particular situations has been confirmed bysolving Saha ionization equation taking into account the ionization potentialdepression (IPD). At these temperatures, low lying excited energy levels ofparent nuclei may have thermal equilibrium population and those excited levelsmay also decay via $\beta^-$ emission. The Nuclear Matrix Element (NME) of allthe transitions of the set of 15 nuclei is calculated using nuclearshell-model. These NME are then used to calculate the comparative half-life($ft_{1/2}$) of the transitions. Calculated terrestrial half-lives of the$\beta^-$ decays are in good agreement with the experimental results in most ofthe cases. Decay to bound and continuum states of bare atoms fromground/isomeric levels and excited nuclear levels have been calculatedseparately. The ratio of bound state to continuum state decay rates as afunction of IPD modified $Q$-value reveals that bound state $\beta^-$ decayrate may compete and even dominate for $Q$-value $<$ 100 keV. The importance ofthe bound state $\beta^-$ decay in stellar situations has been shownexplicitly. We have calculated total $\beta^-$ decay rates (bound state pluscontinuum state) taking into account IPD corrected neutral atom $Q$-value as afunction of density and temperature. We have also presented results for thestellar $\beta^-$ half-lives and compared the ratio of neutral atom to bareatom half-lives for different density and temperature combinations. Theseresults may be useful for s-process nucleosynthesis calculations.

Allowed $\beta^-$ decay of bare atoms with A$\sim$ 60-80 in stellar environments