title: Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions.
abstract: We present shell model calculations for the beta decay of 14C to the 14N ground state, treating the states of the A=14 multiplet as two 0p holes in an 16O core. We employ low-momentum nucleon-nucleon (NN) interactions derived from the realistic Bonn-B potential and find that the Gamow-Teller (GT) matrix element is too large to describe the known lifetime. By using a modified version of this potential that incorporates the effects of Brown-Rho scaling medium modifications, we find that the GT matrix element vanishes for a nuclear density around 85% that of nuclear matter. We find that the splitting between the (J(pi),T)=(1(+),0) and (J(pi),T)=(0(+),1) states in 14N is improved using the medium-modified Bonn-B potential and that the transition strengths from excited states of 14C to the 14N ground state are compatible with recent experiments.
authors: Department of Physics, SUNY, Stony Brook, New York 11794, USA.
authors: J W
authors: JW
authors: Holt
authors: G E
authors: GE
authors: Brown
authors: T T S
authors: TT
authors: Kuo
authors: J D
authors: JD
authors: Holt
authors: R
authors: R
authors: Machleidt