W. Saathoff

Spin alignment and polarisation in the (16O,15N) transfer reactions

The spin alignment of the15N32/* (6.33 MeV) state was measured in the88Sr(16O,15N)89Y reaction atEL=96 MeV using theγ-recoil method. Angular distributions of excited states in15N and89Y were measured with high accuracy. The analysis in terms of DWBA shows that the spin alignment is correctly described by the usual reaction models. The polarisation of the outgoing15N1/2(GS) and15N32/*(6.33 MeV) is discussed. It is shown that cross section differences for transitions to final states with different configurations are sensitive to a spin-orbit potential of15N. The strength and sign of the spin-orbit potential for15N is determined.

Study of the ground state doublet in57Fe

The56Fe(d,p)57Fe reaction has been studied at an incident energy of about 10 MeV. The ground state doublet of57Fe has been resolved using the Heidelberg Q 3 D magnetic spectrograph and the Minnesota split-pole spectrograph. The ratio of the spectroscopic strengths (2J+1)S for the transitions to the first excited state at 14.4 keV excitation energy (Jπ=3/2−) and the ground state (Jπ=1/2−) has been determined to be 5.80±0.5.This number is of special interest with respect to a possible deformation of the nucleus57Fe and in connection with the corresponding analogue resonances in57Co.

The mass of 15B via a three-proton stripping reaction

Abstract The isotope 15B was produced via the reaction 48Ca(18O, 15B)51V. The Q-value and mass excess were determined to be −21.76 ± 0.05 MeV and 28.96 ± 0.05 MeV, respectively. A search for the isotope 14Be was unsuccessful.

The d32 hole strength in the ground state of 44Ca

Abstract The proton stripping reaction 44 Ca (τ, d) 45 Sc (g.s., 12.4 keV) has been studied at E( 3 He ) = 24 MeV with the Heidelberg Q3D magnetic spectrograph. The strength of the transition to the ( d 3 2 ) hole state in 45 Sc was found to be (2 J f +1) C 2 S p =1.9.

Neutron and proton components of nuclear transitions in pion inelastic scattering on 26Mg

Abstract The elastic and inelastic scattering of 180 MeV positive and negative pions from 26 Mg has been measured. From these data the ratios of neutron and proton nuclear transition matrix elements have been determined for the first and second excited states. These ratios are compared with those obtained from electromagnetic transitions in mirror nuclei and with shell model predictions.

Mass excesses of60, 62Fe,68Ni,69Cu,74Zn,73, 75Ga

Accurate, confirmed mass excess values have been determined for the nuclei60, 62Fe,68Ni,69Cu, and73, 75Ga by theQ-value method. The mass of74Zn requires further study. Good agreement was found between experimentally determined mass values and those from mass model predictions.

A comparison of 180 MeV π+ and π− scattering from 24Mg

Abstract Angular distributions for elastic and inelastic scattering of 180 MeV π+ and π− beams for 24Mg have been measured. Optical model calculations for the elastic scattering and DWBA calculations for three inelastic transitions are presented.

Two-proton transfer reaction48Ca(18O,16C)50Ti at 102 MeV

Differential cross sections for18O elastic scattering and the (18O,16C) and (18O,17N) reactions on48Ca were measured at 102 MeV using a Q3D magnetic spectrograph. The transitions to the 7/2− ground state (g.s.) of49Sc and the 0+ (g.s.), 2+ (1.554 MeV), 4+ (2.675 MeV), and 6+ (3.198 MeV) states of50Ti were analyzed by DWBA calculations which include finite-range and recoil effects. Simple cluster-transfer calculations were done for all two-proton transfer transitions. For the 0+ (g.s.) transition a two-nucleon transfer code employing microscopic wave functions was also used. It was found that absolute cross sections for this kinematically well-matched transition were underrated by a factor of about 7 for a reasonable amount of configuration mixing in the nuclear states involved in this transition. This factor is very close to the value 5 derived for the similarly well-matched48Ca(18O,16O)50Ca reaction.