Electromagnetic Production of Kaons

0475082 - ÚJF 2018 CZ eng D - Dizertace
Skoupil, Dalibor
Electromagnetic Production of Kaons.
České vysoké učení technické v Praze, Fakulta jaderná a fyzikálně inženýrská, Katedra fyziky. Obhájeno: Praha. 1.11.2016. - Praha: ČVUT, 2016. 140 s.
Institucionální podpora: RVO:61389005
Klíčová slova: kaon * hyperon * photoproduction * electroproduction * nucleon resonances * isobar model * Regge-plus-resonance model
Kód oboru RIV: BE - Teoretická fyzika

The aim of this work is to provide a deep overview of the strangeness photoproduction reaction and report on recent progress in this field. The kaon photoproduction on the proton is studied either in the resonance region, using an isobar model, or in the resonance region and beyond, exploiting a hybrid Regge-plus-resonace framework. The higher-spin nucleon, spin-3/2 and spin-5/2, and hyperon, spin-3/2, resonances have been included in the model utilizing the consistent formalism by Pascalutsa and they were found to play an important role in data description. The spin-1/2 and spin-3/2 hyperon resonances in combination with the Born terms were revealed to contribute significantly to the background part of the amplitude. The free parameters of the models were fitted to new experimental data from CLAS, LEPS, and GRAAL collaborations, and two versions of the isobar model, BS1 and BS2, and one version of the Regge-plus-resonance model were chosen. All models provide a reasonable overall description of the data in the kinematic regions where the free parameters were adjusted. Even though the kaon photoproduction takes place in the third-resonance region with many resonant states, the total number of included resonances, 15, 16, and 10 in the BS1, BS2, and RPR models, respectively, is quite moderate and it is comparable with amounts of resonances in other models. The sets of chosen nucleon resonances, moreover, overlaps well with the set of the most probable contributing states determined in the Bayesian analysis with the Regge-plus-resonance model.
The candidate is a coauthor of a computational code for the Regge-plus-resonance model, which was exploited to determine the free parameters of the model, two variants of which were then discussed and may be used for further calculations. Subsequently, the candidate helped derive the new amplitude for isobar and Regge-plus-resonance models, including the exchange of high-spin baryon resonances in the consistent formalism.

Trvalý link: http://hdl.handle.net/11104/0271961