Dissertation / PhD Thesis

GSI-2024-01188

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Quasi-Free Scattering off Neutron-Rich Oxygen and Fluorine Isotopes at Relativistic Beam Energies at R3B

Almusidi, T. (Corresponding author)

2025

Abstract: The structure of the neutron-rich oxygen and fluorine isotopes with 11 neutrons up to 14 neutrons has been investigated by utilizing the quasi-free scattering (QFS) in inverse kinematics with a proton-rich target at the R3B setup at GSI-Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. To analyse the reaction channels of interest 19O(p, 2p)18N, 20O(p, 2p)19N, 21F(p, 2p)20O, 22F(p, 2p)21O, and 23F(p, 2p)22O, the delivered relativistic incoming beam from the FRagment Separator (FRS) was identified using a variety of detectors in front of the reaction area. In addition, the outgoing particles are identified around and after the reaction area. Therefore, the ALADIN dipole magnet was used after the reaction area to separate the reaction products. The gathered data were used to deduce the inclusive reduction factor for the simple cases by comparing the inclusive experimental cross section to the total theoretical one of the related orbit based on the eikonal reaction theory. Furthermore, the study presents a comparison between the experimental and theoretical momentum distributions for the residuals of interest. This study has shown a good agreement between the measured and calculated momentum distributions. Furthermore, the obtained inclusive reduction factors support the claim of the weak or no dependence on isospin asymmetry. Moreover, the value of the obtained inclusive reduction factor of the reaction channel 22F(p, 2p)21O is within the range of the reduction factors of the oxygen isotopic chain. Furthermore, the obtained result from testing the future R3B Si-tracker in STFC Daresbury is presented. This tracker aims to increase the sensitivity of hadron-induced quasi-free scattering at the R3B setup.

Note: Dissertation, University of York, 2022

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Contributing Institute(s):

1. Collaboration FAIR: R3B (R3B@FAIR)
2. Kernreaktionen (KRA)

Research Program(s):

1. 612 - Cosmic Matter in the Laboratory (POF4-612) (POF4-612)

Experiment(s):

1. S393: Neutron-rich Nuclei at and Beyond the Dripline in the Range Z=4 to Z=10 Studied in Kinematically Complete Measurements of Direct Reactions at Relativistic Energies (POF3-612; FRS-HTC)

Appears in the scientific report 2025

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