1g(9/2), 1f(5/2), And 1f(7/2) Neutron Inner Hole Responses In Sn-115 And Sn-119 Via The ((D)Over-Right-Arrow,T) Reaction At E-D=200 Mev

Neutron inner hole responses in Sn-115 and Sn-119 nuclei have been studied via the ((d) over right arrow ,t) reaction at E-d=200 MeV using a polarized beam with both vector and tensor components. One-step pickup observables corresponding to the overlapping 1g(9/2), 1f(5/2), and 1f(7/2) responses were analyzed between 3degrees and 15degrees via a least square fit procedure up to E-X=21.5 MeV and 20 MeV in Sn-115 and Sn-119, respectively. The relative enhancement of transitions with high total angular momentum j and the strongly characteristic angular distributions of j(-)=l-1/2 versus j(+)=l+1/2 vector and tensor analyzing powers allow the extraction for the first time of 1f(5/2) and 1f(7/2) strength distributions and of new 1g(9/2) strength in addition to its previously known main component. The standard DWBA analysis is complemented by a refined analysis taking into account the form factor dependence on excitation energy due to the hole coupling with surface vibrations calculated in the framework of the quasiparticle-phonon coupling model (QPMFF). Residual nucleus spectra were measured, mainly in Sn-115, up to E(X)similar to45 MeV where the underlying background of multistep reactions is dominant and can be calibrated. The background of multistep pickup cross section is calculated for the first time in the forward angle region, assuming a dominant role of collective excitations in inelastic steps. Coupled channel calculations for two-step pickup observables involving low multipole collective excitations are performed for comparison. Integrated strengths deduced in the present work are compared with previous data on the 1g(9/2) structure and tail, and with the very limited previous information existing on the 1f strengths. The 1g(9/2), 1f(5/2), and 1f(7/2) QPMFF and standard strength distributions are compared with available theoretical predictions. In particular, we find that the 1f(5/2) and 1f(7/2) strength distributions are not well reproduced by the QPM model. The QPMFF spreading widths are found much narrower than the standard ones, but nevertheless much wider than predicted by theoretical calculations.