Nucleon pickup cross sections to explore nucleon momentum distributions and nuclear structure

  Compared to the projectile fragmentation cross sections, nucleon pickup cross sections at E/A > 100 MeV have not been so well investigated neither experimentally nor theoretically. One-nucleon pickup cross sections may have rich information on, for example, nucleon momentum distribution in nuclei or nuclear structure. Therefore we measured one-nucleon pickup cross sections of ¹⁶O beam at a few 100 MeV/nucleon.
  Primary beams of ¹⁶O with various energies between 100 – 300 MeV/nucleon were provided from HIMAC heavy ion synchrotron at National Institute of Radiological Sciences, Japan, for which cross sections of nucleon pickup reactions on Be target, ⁹Be(¹⁶O, ¹⁷F) and ⁹Be(¹⁶O, ¹⁷O), were measured. At the largest energy of 300 MeV/nucleon, the pickup cross sections show a large enhancement by three orders of magnitude compared to a calculation assuming a Gaussian momentum distribution with the Goldhaber-model width. From the energy dependence of these pickup cross sections, a rough estimate of the nucleon momentum distribution up to 3–4 fm^–1 was deduced. This result will be discussed being compared with several other data and calculations.