Related papers: $1^{++}$ Nonet Singlet-Octet Mixing Angle, Strange…
The $\theta_K$ has been re-evaluated via mass relations and latest experimental results, meanwhile, the $M_{K_{1B}}$ also be obtained. Based on the singlet-octet mixing model and quark-flavor mixing model, the $\theta_{h_1}$ has been…
Due to the SU(3) symmetry breaking effect, the axial-vector kaons $K_1(1270)$ and $K_1(1400)$ are established to be mixtures of two P-wave $K_{1A}\left( {^3{P_1}} \right)$ and $K_{1B}\left( {^1{P_1}} \right)$ states. In QCD sum rules, we…
We determine masses and mixing parameters of the $\eta$ and $M_{\eta^\prime}$ meson in lattice QCD. The calculations are carried out on a set of 13 ETMC gauge ensembles with $N_f=2+1+1$ (maximally) twisted-mass Clover-improved quarks. These…
Analyses of various experimental measurements all indicate that the mixing angle $\theta_{K_1}$ of $K_1(1270)$ and $K_1(1400)$ is in the vicinity of $33^\circ$ or $57^\circ$. However, whether $\theta_{K_1}$ is greater or less than…
The implications of the $f_1(1285)-f_1(1420)$ mixing for the $K_1(^3P_1)-K_1(^1P_1)$ mixing angle is investigated. Based on the $f_1(1285)-f_1(1420)$ mixing angle $\sim 50^\circ$ suggested from the analysis for a substantial body of data…
We study $B_s^0 \to J/\psi f_0(980)$ decays, the quark content of $f_0(980)$ and the mixing angle of $f_0(980)$ and $\sigma(600)$. We calculate not only the factorizable contribution in QCD facorization scheme but also the nonfactorizable…
We study the origins of the inaccuracies of Schwinger's nonet mass, and the Sakurai mass-mixing angle, formulae for the pseudoscalar meson nonet, and suggest new versions of them, modified by the inclusion of the pseudoscalar decay…
Some claim that there are two independent mixing angles ($\theta = 35.3^\circ$, $-54.7^\circ$) between $^3P_1$ and $^1P_1$ states of heavy-light mesons in heavy quark symmetric limit, and others claim there is only one ($\theta =…
We determine the strange quark condensate from lattice QCD for the first time and compare its value to that of the light quark and chiral condensates. The results come from a direct calculation of the expectation value of the trace of the…
Based on a $2\times 2$ mass matrix, the mixing angle of the axial vector states $f_1(1420)$ and $f_1(1285)$ is determined to be $51.5^{\circ}$, and the theoretical results about the decay and production of the two states are presented. The…
We studied properties of the strange axial mesons in the relativized quark model. We calculated the $K_1$ decay constant in the quark model and showed how it can be used to extract the $K_1 (^3P_1) - K_1 (^1P_1)$ mixing angle ($\theta_K$)…
We examine the $\Xi_Q - \Xi'_Q$ mixing and heavy baryon masses in the heavy quark effective theory with the $\mq$ corrections. In the conventional baryon assignment, we obtain the mixing angle $\cos^2 \theta = 0.87\pm 0.03$ in virtue of the…
In a nonrelativistic constituent quark model we find a constraint on the mixing angle of the strange axial-vector mesons, $35^o\stackrel{<}{\sim } \theta _K\stackrel{<}{\sim }55^o,$ determined solely by two parameters: the mass difference…
The masses of the $K_1(^3P_1)$ and $K_1(^1P_1)$ are considered in a nonrelativistic constituent quark model, and the absolute value of the $K_1(^3P_1)-K_1(^1P_1)$ mixing angle is determined to be about $59.29^\circ$. Comparison of the…
We show that the application of Regge phenomenology to SU(4) meson multiplets leads to a new Gell-Mann-Okubo mass-mixing formula in the SU(3) sector, 3m_1^2 + (cos theta)^2 m_0^2 + (sin theta)^2 m_{0'}^2 + sqrt{2} sin(2theta) (m_0^2 -…
We show that all mixing angles are determined, within experimental uncertainty, by a product of SU(2) horizontal symmetries intimately linked to the algebra of weak neutral currents. This concerns: on one hand, the three quark mixing…
The strange quark mass is determined from a new QCD Finite Energy Sum Rule (FESR) optimized to reduce considerably the systematic uncertainties arising from the hadronic resonance sector. As a result, the main uncertainty in this…
It is shown that following experimentally viable expressions for quark mixing angles $\theta_{12}$, $\theta_{23}$, $\theta_{13}$ and CP-violating phase $\delta$: $\sin\theta_{12} = \sqrt{m_{d} / |m_{s}|}$, $\sin\theta_{23} = 2 \, |m_{s}| /…
By incorporating the flavor-dependent quark-antiquark annihilation amplitude into the mass-squared matrix describing the mixing of the isoscalar states of a meson nonet, the new version of Schwinger's nonet mass formula which holds with a…
We determine mass and mixing angles of eta and eta' states using Nf=2+1+1 Wilson twisted mass lattice QCD. We describe how those flavour singlet states need to be treated in this lattice formulation. Results are presented for three values…