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Nuclear Structure and Dynamics, Dubrovnik : Croatie (2009)
Does transfer confirm knockout results for spectroscopic factor suppression with radioactive beams?
J.S. Thomas, N.L. Achouri1, H. Al Falou1, N. I. Ashwood, D. Beaumel2, Y. Blumenfeld2, S. M. Brown, W. N. Catford, R. Chapman, M. Chartier, N. Curtis, G. De France3, F. Delaunay3, N. De Sereville2, B. Fernandez-Domınguez, C. Force3, S. Franchoo2, J. Guillot2, P. Haigh, F. Hammache2, M. Labiche, V. Lapoux, A. Leprince1, R.C. Lemmon, F. Marechal2, B. Martin, X. Mougeot4, B. Mouginot2, L. Nalpas4, A. Navin3, N.A. Orr1, N.P. Patterson, B. Pietras, E.C. Pollacco4, A. Ramus2, M. Rejmund3, J.-A. Scarpaci2, O. Sorlin3, J. Stefan2, G.L. Wilson
(2009)

Proton removal measurements of the (e, e′p), (d,3He), and fast-beam knockout types show a consistent reduction of the spectroscopic factor when compared to shell model calculations [1-3]. The loss of single-particle strength is explained as the result of the short-range correlations between nucleons that are not accounted for in shell model calculations [1,3]. A similar reduction is seen with neutron knockout measurements, as would be expected because of isospin symmetry [1]. The interpretation of these results is complicated by the observation of a dependence of the reduction factor on the asymmetry of the proton and neutron Fermi energy surfaces ( S, with S 0 for near-stable nuclei) [4]. However, the observed trend is largely deduced from measurements of nucleon knockout from exotic nuclei with large values of | S|, and there are no analogous (e, e′n) data to which to compare. It is, therefore, important to supplement these results with data obtained through different reaction mechanisms. The TIARA, MUST2, VAMOS, and EXOGAM systems were employed at the GANIL/SPIRAL facility to provide complete kinematics measurements of the 2H(26Ne,t)25Ne and 1H(26Ne,d)25Ne reactions. The (d, t) and (p, d) reactions, measured in inverse kinematics, provide spectroscopic information on the neutron single-hole states around the new N = 16 shell closure found in the Ne region. The two measurements are designed to provide a comparison of results for the neutron-rich nucleus 26Ne ( S = −12.55 MeV) obtained from the fast-beam neutron knockout reaction [5] and the transfer mechanism studied here. The details of the experimental arrangement and the data analysis, including angular distributions and spectroscopic factors, will be presented.
1 :  LPCC - Laboratoire de Physique Corpusculaire de Caen
2 :  IPNO - Institut de Physique Nucléaire d'Orsay
3 :  GANIL - Grand Accélérateur National d'Ions Lourds
4 :  IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers (ex DAPNIA)
structure nucléaire
Physique/Physique Nucléaire Expérimentale