Beyond mean-field calculations for odd-mass nuclei.

Area of Science:

• Nuclear Physics
• Atomic Nuclei Structure

Background:

• Advanced methods like the generator coordinate method (GCM) excel in describing collective motion in even-even nuclei.
• Current state-of-the-art GCM uses angular-momentum and particle-number projected triaxially deformed Hartree-Fock-Bogoliubov (HFB) states.
• Extending these methods to odd-mass nuclei remains a significant challenge in nuclear physics.

Purpose of the Study:

• To develop and present a novel extension of GCM for odd-mass nuclei.
• To build the generator coordinate space using self-consistently blocked one-quasiparticle HFB states.
• To validate the new method by applying it to ^{25}Mg.

Main Methods:

• Utilizing self-consistently blocked one-quasiparticle HFB states to construct the generator coordinate space.
• Employing the same Skyrme interaction for both mean-field and pairing channels to ensure Pauli principle compliance.
• Applying angular-momentum and particle-number projection techniques.

Main Results:

• The developed method successfully describes the nuclear spectrum, electromagnetic moments, and transition strengths for ^{25}Mg.
• Accurate agreement with experimental data was achieved for both positive and negative parity states.
• The method eliminates the need for effective charges or effective moments in calculations.

Conclusions:

• This work presents the first successful extension of GCM to odd-mass nuclei.
• The method demonstrates the potential for systematic description of odd-A nuclei across the nuclear chart.
• Further refinement of the effective interaction is suggested for improved accuracy.