Proučavanje nuklearne jednadžbe stanja u sudarima izotopa kositra

master's thesis

• Title (english): Study of nuclear equation of state in collisions of tin isotopes
• Author: Ivana Lihtar
• Mentor: Igor Gašparić (mentor)
• Mentor: Matko Milin (komentor)
• Committee member: Matko Milin (predsjednik povjerenstva)
• Committee member: Igor Gašparić (član povjerenstva)
• Committee member: Nils Paar (član povjerenstva)
• Committee member: Mihael Makek (član povjerenstva)
• Committee member: Ivica Smolić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2020-09-04, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

Polazište ovog rada je eksperiment izveden na institutu RIKEN u Japanu u kojem je proučavana nuklearna jednadžba stanja u sudarima izotopa kositra. Energijske distribucije i njihovi omjeri za izospinske parove poput para proton-neutron primjeri su opservabla koje mogu pokazivati osjetljivost na energiju simetrije - najmanje poznat član u nuklearnoj jednadžbi stanja, a u ovakvim sudarima one se nastoje izmjeriti. Cilj rada bio je rekonstruirati ove opservable energije simetrije iz mjerenja neutronskog detektora NeuLAND i vidjeti može li se iz njih zaključiti nešto o parametru γ u potencijalnom članu energije simetrije. Napravljene su simulacije eksperimenta u softverskom okruženju R3BRoot pomoću simulacijskog paketa GEANT4 i pomoću njih je određena efikasnost detekcije protona i neutrona u ovisnosti o energiji što je omogućilo rekonstrukciju distribucija za sustave 132Sn + 124Sn te 124Sn + 112Sn. Distribucije su uspoređene s rezultatima UrQMD transportnog modela za dvije parametrizacije energije simetrije: γ = 0.5 i γ = 1.5. Konačno, raspravljena je mogućnost izbora jedne od njih kao preferirajuće parametrizacije energije simetrije.

Abstract (english)

Starting point of this work is the experiment conducted at RIKEN institute in Japan the focus of the which was the study of nuclear equation of state in collisions of tin isotopes. Energy distributions of isospin pairs like proton-neutron pair and their ratio are examples of observables which can show sensitivity to the symmetry energy - the least known part of nuclear equation of state. Purpose of mentioned collisions is to measure them. Hence, the aim of this work was to reconstruct these observables from measurements made by neutron detector NeuLAND and from them possibly conclude something about the parameter γ in potential part of the symmetry energy. Simulations of the experiment were made using software framework R3BRoot with transport machine GEANT4. Using simulations, proton and neutron efficiencies depending on particle energy were calculated which enabled reconstruction of energy distributions for systems 132Sn + 124Sn and 124Sn + 112Sn. These distributions were compared to UrQMD model results for two parametrizations of symmetry energy, namely γ = 0.5 and γ = 1.5. Work finishes with the discussion weather preference could be given to any of the two as the possible parametrization of symmetry energy.

• Keywords: nuklearna jednadžba stanja; energija simetrije; energijske raspodjele protona i neutrona; simulacije GEANT4; neutronski detektor NeuLAND
• Keywords (english): nuclear equation of state; symmetry energy; energy distributions of protons and neutrons; GEANT4 simulations; neutron detector NeuLAND
• Language: croatian
• URN:NBN: urn:nbn:hr:217:209243
• Study programme: Title: Physics; specializations in: Research; Course: Research; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra fizike (magistar/magistra fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-05 10:49:25