Results 111 to 120 of about 51,008 (236)

Pseudoscalar mesons and instantons [PDF]

open access: yesNuclear Physics B, 1983
Abstract We discuss the QCD sum rules for the correlators of pseudoscalar currents with quantum numbers of π, K, η, η′ mesons. In the framework of the instanton model of the QCD vacuum suggested earlier by the author, we calculate SU(3) breaking effects such as K, η masses and ηη′ mixing, as well as the U(1) breaking effect, the η′ mass.
openaire   +1 more source

Radiative decays of vector and pseudoscalar nonets

open access: yesEPJ Web of Conferences, 2012
Using a counting scheme which treats the light pseudoscalar and the light vector-meson nonet on equal footing, the decays of the narrow light vector mesons into a pseudoscalar meson and a dilepton and of the η′ meson into an ɷ meson and a dielectron are ...
Lutz M.F.M., Leupold S., Terschlüsen C.
doaj   +1 more source

Renormalization of the pseudoscalar operator at four loops in QCD

open access: yesJournal of High Energy Physics
We present the renormalization constant of the pseudoscalar operator defined with a non-anticommuting γ 5 in dimensional regularization up to four-loop order in perturbative Quantum Chromodynamics (QCD).
Long Chen   +2 more
doaj   +1 more source

Search for dark matter produced in association with a Higgs boson decaying to a τ lepton pair in proton-proton collisions at $$\sqrt{s}=13$$ TeV

open access: yesJournal of High Energy Physics
A search for dark matter particles produced in association with a Higgs boson decaying into a pair of τ leptons is performed using data collected in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector.
The CMS collaboration   +2387 more
doaj   +1 more source

Induced Pseudoscalar Coupling Constant

open access: yes, 1998
The recent TRIUMF experiment for $ ^- p \to n _ $ gave a surprising result that the induced pseudoscalar coupling constant $g_P$ was larger than the value obtained from $ ^- p \to n _ $ experiment as much as 44 %. Reexamining contribution of the axial vector current, we found an additional term to the matrix element of Beder and Fearing ...
Cheon, Il-Tong, Cheoun, Myung Ki
openaire   +2 more sources

Chiral SU(3) × SU(3) theorems for pseudoscalar-pseudoscalar scattering amplitudes

open access: yesNuclear Physics B, 1970
Abstract The set of all soft-meson theorems for all scattering amplitudes of the pseudoscalar octet, with two particles off shell, employing PCAC for each pseudoscalar state, current algebra and the σ-terms following from (3, 3 ) + ( 3 ,3) breaking of chiral SU(3) × SU(3) symmetry are given.
openaire   +1 more source

Pseudoscalar Higgs plus jet production at Next-to-Next-to-Leading Order in QCD

open access: yesJournal of High Energy Physics
We present a calculation of pseudoscalar Higgs production in association with a jet at Next-to-Next-to Leading Order (NNLO) accuracy in QCD. We work in an effective field theory in which m t → ∞ resulting in effective operators which couple the ...
Youngjin Kim, Ciaran Williams
doaj   +1 more source

Internal symmetry implications of the Veneziano model in pseudoscalar-pseudoscalar scattering

open access: yesNuclear Physics B, 1969
Abstract The leading order Veneziano model amplitudes for ( J P ) 0 − × 0 − → 0 − × 0 − scattering ∗∗ constrained by the absence of “exotic” resonances, is shown to predict the coupling constant relation of SU(3) coupled with the quark-model/SU(6) ideal singlet-octet mixing in the 1 − , 2 + , nonets.
openaire   +1 more source

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