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Pickup (p,d) reactions on V 51 , Cr 52 , Mn 55 , Fe 54 , Fe 56 , Fe 57 , Fe 58 , Co 59 , Ni 68 , and Ni 60 have been studied using 17.0-and 18.5-MeV protons. The experimental results were analyzed using the predictions of a directreaction model using distorted waves. The distorted-wave theory predicted quite accurately the dependence of cross section on bombarding energy, while the plane wave theory failed in that respect. The ground states of V 51 , Cr 52 , and Fe 54 were found to have almost pure (I/7/2) 8 neutron configurations, thus furnishing more evidence that the I/7/2 neutron shell is a major shell. The results for the heavier nuclei indicate a strong mixing of I/5/2 and 2p neutrons in the ground state. The spin assignments obtained for a few levels are in disagreement with 7-ray angular correlation measurements. INTRODUCTION E XPERIENCE with (p,d) and (d,t) reactions onlight nuclei has shown that these reactions are useful for determining configuration of the target nucleus and in certain cases the neutron configuration of states in the final nucleus. Consequently, there has been considerable interest in studying these reactions on heavier targets. 1-3 In the region with ^4^55, neutrons are filling both the 2p s/2 and l/ B / 2 shells and experimental measurements of the neutron configurations are therefore of great interest.However, the analysis of pickup reactions in this mass region is more complicated than for light nuclei. Distortions are quite important in this mass region so that a simple Butler analysis of the experimental results is too inaccurate. A distorted wave (DW) analysis is an improvement for such reactions but some care is necessary to insure consistency in the extracted results. At the present time the absolute cross sections predicted by the DW theory are uncertain by a factor of about two. The relative cross sections, however, are believed to be much better.This paper presents the results of (p,d) experiments on V 51 , Cr 52 , Fe 54 , Mn 55 , Fe 56 , Fe 57 , Fe 58 , Co 59 , Ni 58 , and Ni 60 . The angular distributions of the deuterons observed show shapes characteristic of 1=1 or 1=3 stripping (pickup) curves. No attempt was made to obtain an optimum DW fit to any of the experiments because of experimental uncertainties. Instead, reasonable optical potentials were chosen a priori and used in the DW predictions. Thus, the DW curves used in this work are predictions and are not fits. However, comparison of the DW predictions with the results of these experiments and with the results of the (p,d) experiments performed at a proton bombarding energy 2

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Measurements of the production cross sections for singly charged molecular ions by high energy (1 MeV/amu) Fq+ (q=4,6–9), Siq+ (q=5,6,8–12), and Cq+ (q=3–6) projectiles incident on a CH4 target are reported. Similar measurements for singly charged recoil ions are presented for H+ (E=1–11 MeV) projectiles incident on CH4. We observed good agreement between our proton results and earlier electron measurements. Theoretical calculations for the sum of the cross sections for production of all singly ionized CHn fragments from CH4 are presented using the Born and Glauber approximations, and both calculated cross sections are in reasonable agreement with the measured cross sections. Production of CH+3, CH+2, CH+, and C+ fragments is analyzed both as a function of projectile charge and projectile velocity. Deviation from quasiequilibrium theory is observed in the relatively small cross section ratios of C+ and CH+ to CH+4 as a function of projectile charge.

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