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Sequential Nature of (p,3p) Two-Proton Knockout from Neutron-Rich Nuclei
A Frotscher1, M Gómez-Ramos1, A Obertelli1,2,3
1Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany.
Physical Review Letters
|July 18, 2020
Summary
Researchers measured two-proton knockout reactions in neutron-rich nuclei. The findings confirm sequential proton-proton collisions, offering insights into nuclear structure and reactions.
Area of Science:
- Nuclear Physics
- High-Energy Nuclear Reactions
- Atomic and Molecular Physics
Background:
- Understanding nuclear structure is crucial for nuclear physics.
- Proton knockout reactions provide insights into nuclear dynamics.
Purpose of the Study:
- To measure two-proton knockout (p,3p) cross sections from neutron-rich nuclei.
- To determine the angular distribution of emitted protons in (p,3p) reactions.
- To investigate the reaction mechanism in neutron-rich nuclei.
Main Methods:
- Measurements were conducted in inverse kinematics using neutron-rich nuclei.
- Proton knockout cross sections were determined at approximately 250 MeV/nucleon.
- Angular distributions of three emitted protons were analyzed.
Main Results:
- The angular distribution of three emitted protons was determined for the first time.
- Kinematics indicate two sequential proton-proton collisions within the projectile nucleus.
- Ratios of (p,3p) to (p,2p) cross sections support a sequential reaction mechanism.
Conclusions:
- The (p,3p) reaction mechanism in neutron-rich nuclei is consistent with sequential proton-proton collisions.
- These findings reinforce the understanding of many-nucleon removal reactions.
- The study provides valuable data for nuclear structure models.
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