η and η ′ Production in J / ψ Radiative Decays from Quantum Chromodynamics
Year: 2025
Type: article
Abstract: We present a first principles calculation within quantum chromodynamics (QCD) of the radiative decays of the J/ψ into the light pseudoscalar mesons η and η^{'}. Within a lattice computation we obtain the transition form factors as a function of photon virtuality from the timelike region, accessible experimentally via the "Dalitz" decay J/ψ→e^{+}e^{-}η^{(')}, through to the real photon point corresponding to J/ψ→γη^{(')}. This is the first calculation in lattice QCD with two (heavier than physical) degenerate flavors of light quark and a heavier strange quark, in which the η^{'} appears as the first excited state with pseudoscalar isoscalar quantum numbers. We access it reliably by using variationally optimized operators, the use of which also improves the purity of the J/ψ and η signals, reducing systematic uncertainties. High quality results at a large number of kinematic points are obtained in a typically noisy disconnected process by using a novel correlator averaging procedure. Our results show the expected enhanced production of the η^{'} over the η in this process, and suggest that the demonstrated lattice technology is suitable for future calculations considering processes in which light meson resonances are produced.
Source: Physical Review Letters
DOI: 10.1103/tdk2-bk8w
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,750
Funders: State of Illinois, National Science Foundation, U.S. Department of Energy, College of William and Mary, University of Texas at Austin, National Energy Research Scientific Computing Center, Office of Science, National Nuclear Security Administration, Office of Advanced Research Computing, Rutgers, The State University of New Jersey, Engineering and Physical Sciences Research Council, Science and Technology Facilities Council, Nuclear Physics, Lawrence Berkeley National Laboratory
Awards: G1143651532, G121915436, G1553439044, G1796307089, G2263355576, Peta-5: A National Facility for Petascale Data Intensive Computation and Analytics, G2952167421, G3226045097, The DiRAC 2.5x Facility, DiRAC 2.5 Operations 2017-2020, Sustained-Petascale In Action: Blue Waters Enabling Transformative Science And Engineering, MESON SPECTROSCOPY FROM QCD, DiRAC 2.5 - the pathway to DiRAC Phase 3
OpenAlex ID: W4415261905