Results 31 to 40 of about 1,774 (184)

Heavy-quark spin symmetry breaking in the Born-Oppenheimer approximation

Journal of High Energy Physics, 2023
Heavy-quark spin symmetry is explicitly broken by the mass splitting between a heavy-light pseudoscalar meson and its vector partner. This fact plays a pivotal role in the physics of states whose mass lies close to the threshold of an open-flavor meson ...
R. Bruschini
doaj   +1 more source

Effects of light-by-light scattering in the Lamb shift and hyperfine structure of muonic hydrogen [PDF]

EPJ Web of Conferences, 2019
We calculate the meson exchange contribution to the interaction operator of muon and proton, which is determined by the meson coupling with two photon state.
Dorokhov A. E., Martynenko A. P., Martynenko F. A., Radzhabov A. E.   +3 more
doaj   +1 more source

Excited vector mesons: phenomenology and predictions for a yet unknown vector ss state with a mass of about 1.93 GeV

EPJ Web of Conferences, 2018
The firm understanding of standard quark-antiquark states (including excited states) is necessary to search for non-conventional mesons with the same quantum numbers.
Piotrowska M., Giacosa F.
doaj   +1 more source

Towards a precise determination of the scattering amplitudes of the charmed and light-flavor pseudoscalar mesons

European Physical Journal C: Particles and Fields, 2019
We study the scattering of the light-flavor pseudoscalar mesons ($$\pi , K, \eta $$ π,K,η ) off the ground-state charmed mesons ($$D,D_s$$ D,Ds ) within chiral effective field theory.
Zhi-Hui Guo, Liuming Liu, Ulf-G. Meißner, J. A. Oller, A. Rusetsky   +4 more
doaj   +1 more source

A tmQCD mixed-action approach to flavour physics

EPJ Web of Conferences, 2018
We discuss a mixed-action approach in which sea quarks are regularised using non-perturbatively O(a) improved Wilson fermions, while a fully-twisted tmQCD action is used for valence quarks.
Herdoíza Gregorio, Pena Carlos, Preti David, Romero José Ángel, Ugarrio Javier   +4 more
doaj   +1 more source

Mass Spectrum of Noncharmed and Charmed Meson States in Extended Linear-Sigma Model

Particles
The mass spectrum of different meson particles is generated using an effective Lagrangian of the extended linear-sigma model (eLSM) for scalar and pseudoscalar meson fields and quark flavors, up, down, strange, and charm.
Azar I. Ahmadov, Azzah A. Alshehri, Abdel Nasser Tawfik   +2 more
doaj   +1 more source

Model discrimination in pseudoscalar-meson photoproduction

Physics Letters B, 2016
To learn about a physical system of interest, experimental results must be able to discriminate among models. We introduce a geometrical measure to quantify the distance between models for pseudoscalar-meson photoproduction in amplitude space ...
J. Nys, J. Ryckebusch, D.G. Ireland, D.I. Glazier   +3 more
doaj   +1 more source

Meson electromagnetic form factors

EPJ Web of Conferences, 2012
The electromagnetic structure of the pseudoscalar meson nonet is completely described by the sophisticated Unitary&Analytic model, respecting all known theoretical properties of the corresponding form factors.
Dubničková Anna Z., Dubnička Stanislav   +1 more
doaj   +1 more source

Study of Semileptonic B⟶DPℓ+νℓ Decays Based on the SU(3) Flavor Symmetry

Advances in High Energy Physics, Volume 2025, Issue 1, 2025.
Decays B⟶DPℓ+νℓ(ℓ = e, μ, τ) with the nonresonance, the charmed vector resonances, the charmed scalar resonances, and the charmed tensor resonances are explored by using the SU(3) flavor symmetry approach. Firstly, the decay amplitudes of different modes are related by the SU(3) flavor symmetry.
Ru-Min Wang, Yi-Jie Zhang, Meng-Yuan Wan, Xiao-Dong Cheng, Yuan-Guo Xu, Subhash Singha   +5 more
wiley   +1 more source

Gamma-gamma physics and meson transition form factors [PDF]

EPJ Web of Conferences, 2020
I summarize recent experimental results for two photon production of mesons. These processes include the neutral pion, η and η′ transition form factors and two photon production of pseudoscalar meson pairs.
Kupsc Andrzej
doaj   +1 more source