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arXiv · 1212.3375

Quantum Monte Carlo calculations of electromagnetic moments and transitions in A <= 9 nuclei with meson-exchange currents derived from chiral effective field theory

S. Pastore·Steven C. Pieper·R. Schiavilla·R. B. Wiringa
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Abstract

Quantum Monte Carlo calculations of electromagnetic moments and transitions are reported for A <= 9 nuclei. The realistic Argonne v18 two-nucleon and Illinois-7 three-nucleon potentials are used to generate the nuclear wave functions. Contributions of two-body meson-exchange current (MEC) operators are included for magnetic moments and M1 transitions. The MEC operators have been derived in both a standard nuclear physics approach and a chiral effective field theory formulation with pions and nucleons including up to one-loop corrections. The two-body MEC contributions provide significant corrections and lead to very good agreement with experiment. Their effect is particularly pronounced in the A=9, T=3/2 systems, in which they provide up to 20% (40 %) of the total predicted value for the 9Li (9C) magnetic moment.

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S. Pastore, Steven C. Pieper, R. Schiavilla, R. B. Wiringa. 2013-02-28. Quantum Monte Carlo calculations of electromagnetic moments and transitions in A <= 9 nuclei with meson-exchange currents derived from chiral effective field theory. https://doi.org/10.1103/physrevc.87.035503

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