Effective Interaction and the ReactionsLi7(p, p′

Abstract

The total cross sections for the reactions 7 Li(£,£') 7 Li(478 keV) and 7 Li(£,ra) 7 Be(431 keV) have been measured for proton energies between 23 and 52 MeV and compared with the predictions of a microscopic model of the reaction. The spin-flip, isospin-flip part of the effective interaction is found to be essentially independent of energy, whereas the pure central part appears to decrease with increasing energy.

Nucleon Charge-Exchange Reactions at Intermediate Energy

“…However, in the 14 C(p,n) reaction, the transition to the ground state of 14 N was found to be much stronger than predicted from the strength of the corresponding beta decay and this indicated the importance of the tensor part of the effective interaction. Also, for the 18 O target, transitions were observed leading to known states with J π = 2 + , indicating contributions from multipole components of the interaction with ∆ L = 2.…”

“…In these, the most clear-cut conclusions were obtained from studies of the (p,n) reaction on the J π = 0 + , T = 1 targets 14 C [17] and 18 O [16]. In both cases the reaction populated final states with J π = 0 + via the V component of the interaction and states with J π = 1+ via Vσ and reaction calculations using very simple shell model wave functions yielded estimates of the interaction strengths.…”

“…During the following decade a number of studies investigated the properties of the isovector effective interaction utilizing the correspondence between betadecay matrix elements and those for the (p, n) reaction cross section [ 16,17,18,19,20,21]. It was recognized that the momentum transfer in beta decay was small, so that the transition amplitude for the (p,n) reaction should also be evaluated for q 0, i.e., near scattering angle θ = 0.…”

Reactions leading to the first excited states ofLi7andBe7and isospin-mixed states inAustin1, Paul2, Brown3 et al. 2019Phys. Rev. C1000View full textAdd to dashboardCite

“…The values of (p, n )/(p, p ) are generally much less than one, owing to contributions from direct processes. Measurements in the 20 to 50 MeV range [9], find values of about one-third because the effective interaction mediating inelastic scattering is significantly larger than that mediating charge exchange. The dominant feature of Fig.…”

Some observations concerning the use of realistic forces in a microscopic description of the inelastic scattering of nucleons from nuclei at medium energies

“…A state of the target nucleus is defined by its total angular momentum, projection, and additional quantum numbers; the internal state of the projectile nucleon 12 is fixed by giving its spin and i-spin projection; thus . .…”