Substantial Nuclear Hyperfine Mixing Effect in Boronlike ^{205}Pb Ions

Area of Science:

• Nuclear Physics
• Atomic Physics
• Quantum Control

Background:

• Nuclear Hyperfine Mixing (NHM) traditionally studied in relation to Thorium-229 due to its low-lying isomeric state.
• Limited understanding of NHM's broader applicability beyond specific isotopes.
• Need for new systems to experimentally probe and validate NHM phenomena.

Purpose of the Study:

• To develop a general theoretical framework for Nuclear Hyperfine Mixing (NHM).
• To investigate the potential for substantial NHM effects in isotopes beyond ^{229}Th.
• To identify new candidate systems for studying and controlling nuclear properties via NHM.

Main Methods:

• Development of a generalized theoretical model for Nuclear Hyperfine Mixing (NHM).
• Application of the theory to analyze boronlike ^{205}Pb ions (specifically, ^{205}Pb^{77+}).
• Calculation of nuclear transition energies and isomer lifetimes.

Main Results:

• Prediction of a significant Nuclear Hyperfine Mixing (NHM) effect in boronlike ^{205}Pb^{77+} ions.
• Observed a substantial reduction in the radiative lifetime of the ^{205}Pb isomer by four orders of magnitude (from 15 minutes to 32 milliseconds).
• Identified the opening of a previously forbidden magnetic dipole channel as the mechanism driving the enhanced NHM effect.

Conclusions:

• Boronlike ^{205}Pb^{77+} ions exhibit a surprisingly strong Nuclear Hyperfine Mixing (NHM) effect.
• The NHM effect in ^{205}Pb^{77+} is driven by a novel magnetic dipole transition pathway.
• ^{205}Pb ions present a promising new system for experimental investigation and validation of Nuclear Hyperfine Mixing (NHM) phenomena.