Dynamical generation of hadronic resonances in effective models with derivative interactions
- Light scalar mesons can be understood as dynamically generated resonances. They arise as 'companion poles' in the propagators of quark-antiquark seed states when accounting for hadronic loop contributions to the self-energies of the latter. Such a mechanism may explain the overpopulation in the scalar sector - there exist more resonances with total spin J=0 than can be described within a quark model. Along this line, we study an effective Lagrangian approach where the isovector state a_{0}(1450) couples via both non-derivative and derivative interactions to pseudoscalar mesons. It is demonstrated that the propagator has two poles: a companion pole corresponding to a_{0}(980) and a pole of the seed state a_{0}(1450). The positions of these poles are in quantitative agreement with experimental data. Besides that, we investigate similar models for the isodoublet state K_{0}^{*}(1430) by performing a fit to pion-kaon phase shift data in the I=1/2, J=0 channel. We show that, in order to fit the data accurately, a companion pole for the K_{0}^{*}(800), that is, the light kappa resonance, is required. A large-N_{c} study confirms that both resonances below 1 GeV are predominantly four-quark states, while the heavy states are quarkonia.
Author: | Thomas Wolkanowski-Gans |
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URN: | urn:nbn:de:hebis:30:3-414141 |
Publisher: | Univ.-Bibliothek |
Place of publication: | Frankfurt am Main |
Referee: | Francesco GiacosaORCiDGND, Dirk H. RischkeORCiDGND |
Document Type: | Doctoral Thesis |
Language: | English |
Year of Completion: | 2016 |
Year of first Publication: | 2016 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Granting Institution: | Johann Wolfgang Goethe-Universität |
Date of final exam: | 2016/08/10 |
Release Date: | 2016/08/12 |
Page Number: | XIX, 105 |
Note: | Zusammenfassung auf Deutsch |
HeBIS-PPN: | 385754116 |
Institutes: | Physik |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Sammlungen: | Universitätspublikationen |
Licence (German): | Deutsches Urheberrecht |