2014/11/24 by Damir Becirevic, Damir Bečirević, Michael Kruse +1 · 1 citation
Physics and Astronomy · #Computation #Hadron #High-Energy Particle Collisions Research #Lattice (music) #Lattice QCD #Lattice field theory #Matrix element #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark #Radiative transfer #hep-ex #hep-lat #hep-ph
paper · pdf · doi:10.1007/jhep05(2015)014
19 pages, 4 figs
arxiv created 2014/11/24 · openalex publication_date 2015/05/01 · arxiv updated 2015/06/11 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We compute the hadronic matrix element relevant to the physical radiative decay η c (2S) → J/ψγ by means of lattice QCD. We use the (maximally) twisted mass QCD action with N f = 2 light dynamical quarks and from the computations made at four lattice spacings we were able to take the continuum limit. The value of the mass ratio m ηc (2S)/m ηc(1S) we obtain is consistent with the experimental value, and our prediction for the form factor is V ηc(2S)→J/ψΥ (0) ≡ V 12(0) = 0.32(6)(2), leading to Γ(η c (2S) → J/ψγ) = (15.7 ± 5.7) keV, which is much larger than Γ(ψ(2S) → η c γ) and within reach of modern experiments.