2008/07/31 by Diogo Boito, Diogo R. Boito, Rafel Escribano +1 · 73 citations
Mathematics · Physics and Astronomy · #Curvature #Dispersion relation #Distribution (mathematics) #Energy (signal processing) #Form factor (electronics) #Geometry #High-Energy Particle Collisions Research #Mathematical analysis #Mathematics #Meson #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Physics #Plane (geometry) #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Resonance (particle physics) #Scalar (mathematics) #Unitarity #Vector meson #hep-ex #hep-lat #hep-ph #nucl-th
paper · pdf · doi:10.1140/epjc/s10052-008-0834-9
published in The European Physical Journal C 59(4) (Springer Science+Business Media) · 16 pages, 1 figure, version to appear in Eur. Phys. J. C
arxiv created 2008/12/02 · openalex publication_date 2008/12/15 · arxiv updated 2009/12/01 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
Recent experimental data for the differential decay distribution of the decay τ-→ντKSπ- by the Belle collaboration are described by a theoretical model which is composed of the contributing vector and scalar form factors F+Kπ(s) and F0Kπ(s). Both form factors are constructed such that they fulfil constraints posed by analyticity and unitarity. A good description of the experimental measurement is achieved by incorporating two vector resonances and working with a three-times subtracted dispersion relation in order to suppress higher-energy contributions. The resonance parameters of the charged K^*(892) meson, defined as the pole of F+Kπ(s) in the complex s-plane, can be extracted, with the result MK^*=892.0 ± 0.9 MeV and ΓK^*=46.2 ± 0.4 MeV. Finally, employing the three-subtracted dispersion relation allows to determine the slope and curvature parameters λ+'=(24.7± 0.8)⋅ 10-3 and λ+''=(12.0± 0.2)⋅ 10-4 of the vector form factor F+Kπ(s) directly from the data.