Reconciliation of Theoretical Lifetimes of the $5s5p\,^3\!P^{\rm o}_2$ Metastable State for $^{88}$Sr with Measurement: The Role of the Blackbody-Radiation-Induced Decay
Benquan Lu1, Xiaotong Lu1, Jiguang Li2*, and Hong Chang1,3*
1National Time Service Center, Chinese Academy of Sciences, Xi'an 710600, China 2Institute of Applied Physics and Computational Mathematics, Beijing 100088, China 3The University of Chinese Academy of Sciences, Beijing 100088, China
Abstract：We conducted measurement and calculation to resolve the long-standing large discrepancy in the metastable state lifetime for the $^{88}$Sr atom between theoretical and experimental results. The present lifetime $\tau = 830_{-240}^{+600}$ s, measured using the magneto-optical trap as a photon amplifier to detect the weak decay events, is approximately 60% larger than the previous experimental value $\tau = 520_{-140}^{+310}$ s. By considering the electron correlation effects in the framework of the multiconfiguration Dirac–Hartree–Fock theory, we obtained a theoretical lifetime of 1079(54) s, which lies in the range of measurements with error bars. Furthermore, we considered the higher-order electron correlation and Breit interaction to control the uncertainty of the theoretical calculation. The significant improvement in the agreement between calculations and measurements is attributed to the updated blackbody radiation-induced decay rate.
. [J]. 中国物理快报, 2022, 39(7): 73201-.
Benquan Lu, Xiaotong Lu, Jiguang Li, and Hong Chang. Reconciliation of Theoretical Lifetimes of the $5s5p\,^3\!P^{\rm o}_2$ Metastable State for $^{88}$Sr with Measurement: The Role of the Blackbody-Radiation-Induced Decay. Chin. Phys. Lett., 2022, 39(7): 73201-.
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