The shell closure effects on α-decay half-lives with an improved formula.

An improved formula including shell closure effects is proposed to investigate α-decay half-lives. The coefficients of the improved formula are obtained by fitting the experimental α-decay half-lives of 677 nuclei with 62≤Z≤118. The root mean square deviation between α-decay half-lives calculated by the improved formula and experimental data is reduced from 0.435 to 0.385. The result indicates that the improved formula considering the shell closure effects is reliable in reproducing the experimental α-decay half-lives. In addition, the improved formula is extended to predict α-decay half-lives of nuclei with Z=119, 120 isotopes. The results of the predicted α-decay half-lives indicate that N=184 appears to be the next magic number beyond N=126. [ABSTRACT FROM AUTHOR]