Clustering in neutron-rich light nuclei produced in reactions of 9Li beam on LiF target

doctoral thesis

• Title (croatian): Klasterska građa neutronski bogatih lakih jezgara proizvedenih u reakcijama snopa 9Li na meti LiF
• Author: Nikola Vukman
• Mentor: Neven Soić (mentor)
• Committee member: Matko Milin (predsjednik povjerenstva)
• Committee member: Neven Soić (član povjerenstva)
• Committee member: Tamara Nikšić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2022-12-20, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics
• Universal decimal classification (UDC): 53 - Physics

Abstract

The results presented in this thesis are based on the analysis of the S1620 experiment performed at TRIUMF, where multi-nucleon and cluster transfer reactions of the 9^Li beam of 74.8 MeV on the ≈ 1 mg/cm2 LiF target were used to populate excited states of neutron-rich light nuclei 10^Be, 12^Be and 13^B. The main motivation behind this work was the need for experimental data to wage on the existence of molecular-like structures in the excited states of these nuclei and to resolve inconsistent observations from the previous measurements. For the latter two nuclei, the use of transfer reactions and resonant particle spectroscopy method to study molecular structures is independent and novel approach to more commonly used resonant elastic scattering and inelastic breakup measurements. Most important results are the first experimental observation of the decays of the 12^Be excited states to the 6^He+6^He* (1.8 MeV, 2^+) channel and the 13^B decays to the 10^Be+3^H and 7^Li+6^He channels. In the 10^Be nucleus, new states were observed in the 8^Be+nn decay channel and past results for the 4^He+6^He* (1.8 MeV, 2^+) channel were confirmed, alongside newly observed states. In both cases only one previous measurement was available. New states were observed in the 4^He+6^He, 4,6^He+8,6^He and 9^Li+4^He decay channels of the 10^Be, 12^Be and 13^B nuclei, respectively. Even though branching ratios were not determined, due to limited resolution of the present data, important spectroscopic information on the cluster structures in these nuclei was obtained, which could be related to the molecular α-Xn- α and α-2n-t-α structure of the 10,12^Be and 13^B nuclei, respectively.

Abstract (english)

Rad ne sadrži sažetak na drugom jeziku.

• Keywords: clustering in neutron-rich light nuclei; nuclear molecules; 10Be; 12Be; 13B; transfer reactions; resonant particle spectroscopy
• Keywords (english): klasteriranje u neutronski bogatim lakim jezgrama; nuklearne molekule; 10Be; 12Be; 13B; reakcije prijenosa nukleona; rezonantna čestična spektroskopija
• Language: english
• URN:NBN: urn:nbn:hr:217:044391
• Promotion: 2023
• Study programme: Title: Physics; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje fizika (doktor/doktorica znanosti, područje prirodnih znanosti, polje fizika)
• Type of resource: Text
• Extent: 184 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-01-13 10:11:34