Theoretical analysis of the electron bridge process in ${}^{229}$Th${}^{3+}$

Abstract

We investigate the deexcitation of the ${}^{229}$Th nucleus via the excitation of an electron. Detailed calculations are performed for the enhancement of the nuclear decay width due to this so called electron bridge (EB) compared to the direct photoemission from the nucleus. The results are obtianed for triply ionized thorium by using a B-spline pseudo basis approach to solve the Dirac equation for a local $x_{\alpha }$ potential. This approach allows for an approximation of the full electron propagator including the positive and negative continuum. We show that the contribution of continua slightly increases the enhancement compared to a propagator calculated by a direct summation over bound states. Moreover we put special emphasis on the interference between the direct and exchange Feynman diagrams that can have a strong influence on the enhancement.

References in corpus (8)

• Direct detection of the 229Th nuclear clock transition
• Excitation of the isomeric ^{229m}Th nuclear state via an electronic bridge process in ^{229}Th^+
• Nuclear clocks based on resonant excitation of gamma-transitions
• Radiative lifetime and energy of the low-energy isomeric level in ${}^{229}$Th
• Theory of nuclear excitation by electron capture for heavy ions
• Many-electron effects on the x-ray Rayleigh scattering by highly charged He-like ions
• Observation of an unexpected negative isotope shift in 229Th+ and its theoretical explanation
• Nuclear excitation by two-photon electron transition

Cited by in corpus (4)

• The ${}^{229}$Th isomer: prospects for a nuclear optical clock
• A scheme for excitation of thorium-229 nuclei based on the electronic bridge excitaion
• Development of a recoil ion source providing slow Th ions including ${}^{229(m)}$Th in a broad charge state distribution
• Theoretical evaluation of decay mode of ${}^{229m}\mathrm{Th}$ in solid samples