De Ratio

This is an older PRL editor’s pick from Oct. 2007.  It is of particular interest that the mean-life of 14C is unexpectedly long for its initial and final state (J,T) values.  Are there external interactions that could further affect the transition matrix?

Abstract:

“We present shell model calculations for the beta-decay of the 14C ground state 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 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,T)=(1+,0) and (J,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.”

arXiv:0710.0310v2 [nucl-th] [PDF]

On the home page it is my intent to post a paper of particular interest in the field of nuclear theory (or closely related) from time to time.  The papers will mostly be selected from recent pre-releases, as posted to the Archives, or PRL editor picks.  When applicable, notes may be included.