A Laser Excitation Scheme for ^{229m}Th.

Area of Science:

• Nuclear physics
• Laser spectroscopy
• Quantum mechanics

Background:

• Direct laser excitation of the lowest nuclear excited state in Thorium-229 (229Th) is a long-standing goal.
• Current methods require highly precise excitation energy values for 229Th, which are not yet available.

Purpose of the Study:

• To present a novel direct laser excitation scheme for the 229Th isomer (229mTh).
• To circumvent the requirement for a reduced uncertainty in the isomer's excitation energy.
• To enable nuclear laser spectroscopy with existing laser technology.

Main Methods:

• Proposed a laser excitation scheme for 229mTh.
• Utilized the internal-conversion decay channel of the isomeric state for probing population.
• Leveraged existing laser technology.

Main Results:

• The proposed scheme bypasses the need for reduced excitation energy uncertainty.
• Achievable signal-to-background ratio greater than 10^4.
• Feasible total measurement time of less than three days for laser scanning.

Conclusions:

• The developed scheme paves the way for nuclear laser spectroscopy of 229mTh.
• Demonstrates the feasibility of probing isomeric population using internal conversion decay.
• Highlights the potential of using existing laser technology for nuclear excitation studies.