Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range

Research output: Contribution to journalArticle


The quasi-free scattering reactions 11C(p,2p) and 10,11,12C(p,pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and proton-neutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p,2p) and 12C(p,pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of single-particle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p,2p) are found to be 'significantly smaller than for (p,pn) reactions for all investigated nuclei. © 2019 The Authors


External organisations
  • Technical University of Darmstadt
  • GSI Helmholtz Centre for Heavy Ion Research
  • Saint Mary's University
  • Dresden University of Technology
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Other Physics Topics


  • Inverse kinematics, Quasi-free scattering, Shell model, Spectroscopic factors
Original languageEnglish
Pages (from-to)682-688
Number of pages7
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Publication statusPublished - 2019 Aug 10
Publication categoryResearch

Bibliographic note

Export Date: 22 July 2019