2017/10/31 by Martin Hoferichter, Bastian Kubis, Marvin Zanke · 1 citation
Mathematics · Physics and Astronomy · #Algorithm #Amplitude #Geometry #Mathematics #Meson #Nuclear physics research studies #Particle physics #Particle physics theoretical and experimental studies #Physics #Pi #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Radiative transfer #hep-ex #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevd.96.114016
published as Phys. Rev. D 96, 114016 (2017) · 7 pages, 3 figures; journal version
openalex created_date 2017/10/20 · openalex publication_date 2017/12/14 · arxiv created 2017/12/15 · arxiv updated 2017/12/18 · openalex updated_date 2026/08/05
Studies of the reaction \ensuremathγ\ensuremathπ\ensuremath→\ensuremathπ\ensuremathπ, in the context of the ongoing Primakoff program of the COMPASS experiment at CERN, give access to the radiative couplings of the \ensuremathρ(770) and \ensuremathρ3(1690) resonances. We provide a vector-meson-dominance estimate of the respective radiative width of the \ensuremathρ3, \mathrm\ensuremathΓ_\ensuremathρ3\ensuremath→\ensuremathπ\ensuremathγ=48(18) keV, as well as its impact on the F-wave in \ensuremathγ\ensuremathπ\ensuremath→\ensuremathπ\ensuremathπ. For the \ensuremathρ(770), we establish the formalism necessary to extract its radiative coupling directly from the residue of the resonance pole by analytic continuation of the \ensuremathγ\ensuremathπ\ensuremath→\ensuremathπ\ensuremathπ amplitude to the second Riemann sheet, without any reference to the vector-meson-dominance hypothesis.