Effects of electron screening on $\alpha$-decay half-lives in different external environments

In this paper, the electron screening effects on $\alpha$-decay half-lives are investigated in different external environments, including $\alpha$ decays in neutral atoms, in metal, and in extremely strong magnetic-field environments. Systematic calculations of $\alpha$-decay half-lives are performed for $\alpha$ emitters with proton number $Z=52$–105. By taking into account the electron screening effects, the interaction potential between $\alpha$ particle and daughter nucleus, and the decay energy are both changed in external environments. From the numerical results, it is found that the $\alpha$-decay half-lives in external environments are changed by a factor of from $5\times {10}^{-4}$% to 11.46% due to the electron screening effects. Moreover, we find that the electron screening effect is closely related to the decay energy of the bare nucleus and its proton number. To measure the electron screening effects in experiments, it is suggested to select the $\alpha$-decay candidates with relatively low decay energies and proper decay half-lives.

Figure 1

Sketch of the screened potential $V_{\mathrm{equ}}\left(R\right)$ and the nonscreened potential $V_B\left(R\right)\mathrm{.}R$ is the relative distance and $Q_B$ is the decay energy of the bare nucleus.

Figure 2

The relative variation ${\mathrm{\Delta }}_{\mathrm{sc}}=(T_{\mathrm{sc}}-T_{\mathrm{bare}})/T_{\mathrm{bare}}$ in neutral atoms (a), in metal (b), and in a magnetic-field environment with $b={10}^3$ (c), $b={10}^4$ (d), $b={10}^5$ (e), and $b={10}^6$ (f).

Figure 3

The dependence of ${\mathrm{\Delta }}_{\mathrm{SC}}$ on the decay energy of the bare nucleus $Q_B$ for a typical isotopic chain of $Z=75\mathrm{.}$

Figure 4

The ratio of magnetic screened to bare half-lives $f_{\alpha }=T_{\mathrm{Mag}}/T_{\mathrm{bare}}$ for ${}^{235}\mathrm{U}$ with different magnetic field strengths $b=B/B_0\mathrm{.}$