Abstract
Light scalar hadrons can be understood as dynamically generated resonances. These arise as `companion poles' in the propagators of quark-antiquark seed states when accounting for meson-loop contributions to the self-energies of the latter. Along this line, we extend previous calculations of T\"ornqvist and Roos and of Boglione and Pennington, where the resonance $a_{0}(980)$ appears as companion pole in the propagator of $a_{0}(1450)$ which is predominantly a quark-antiquark state. We also construct an effective Lagrangian where $a_{0}(1450)$ couples to pseudoscalar mesons with both non-derivative and derivative interactions. Computing the one-loop self-energy, we demonstrate 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.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
