TY - JOUR

T1 - He6β-decay rate and the suppression of the axial constant in nuclear matter

AU - Vaintraub, Sergey

AU - Barnea, Nir

AU - Gazit, Doron

PY - 2009/6/29

Y1 - 2009/6/29

N2 - We present a microscopic calculation of the He6β-decay into the ground state of Li6. To this end, we use chiral perturbation theory at next-to-next-to-next-to-leading order to describe the nuclear weak-currents. The nuclear wave functions are derived from the J-matrix inverse scattering nucleon-nucleon potential (JISP), and the Schrödinger equation is solved using the hyperspherical-harmonics expansion. Our calculation brings the theoretical decay-rate within 3% of the measured one. This success is attributed to the use of chiral perturbation theory based mesonic currents, whose contribution is qualitatively different compared to the standard nuclear physics approach, where the use of meson exchange currents worsens the comparison to experiment. The inherent inconsistency in the use of the JISP potential together with chiral perturbation theory based is argued not to affect this conclusion, though a more detailed investigation is called for. We conclude that any suppression of the axial constant in nuclear matter is included in this description of the weak interaction in the nucleus.

AB - We present a microscopic calculation of the He6β-decay into the ground state of Li6. To this end, we use chiral perturbation theory at next-to-next-to-next-to-leading order to describe the nuclear weak-currents. The nuclear wave functions are derived from the J-matrix inverse scattering nucleon-nucleon potential (JISP), and the Schrödinger equation is solved using the hyperspherical-harmonics expansion. Our calculation brings the theoretical decay-rate within 3% of the measured one. This success is attributed to the use of chiral perturbation theory based mesonic currents, whose contribution is qualitatively different compared to the standard nuclear physics approach, where the use of meson exchange currents worsens the comparison to experiment. The inherent inconsistency in the use of the JISP potential together with chiral perturbation theory based is argued not to affect this conclusion, though a more detailed investigation is called for. We conclude that any suppression of the axial constant in nuclear matter is included in this description of the weak interaction in the nucleus.

UR - http://www.scopus.com/inward/record.url?scp=67650488411&partnerID=8YFLogxK

U2 - 10.1103/PhysRevC.79.065501

DO - 10.1103/PhysRevC.79.065501

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AN - SCOPUS:67650488411

SN - 0556-2813

VL - 79

JO - Physical Review C - Nuclear Physics

JF - Physical Review C - Nuclear Physics

IS - 6

M1 - 065501

ER -