arXiv subjects

Z. R. Kordov

Publications and source records attributed to Z. R. Kordov.

3 recordsLinked to original sources

arXiv2023

Weak decay constants of the neutral pseudoscalar mesons from lattice QCD+QED

With increasing requirements for greater precision, it becomes essential to describe the effects of isospin breaking induced by both quark masses and electro-magnetic effects. In this work we perform a lattice analysis of the weak decay constants of the neutral pseudoscalar mesons including such isospin breaking effects, with particular consideration being given to the state mixing of the $π^0$, $η$ and $η^\prime$. We also detail extensions to the non-perturbative RI$^\prime$-MOM renormalization scheme for application to non-degenerate flavour-neutral operators which are permitted to mix, and present initial results. Using flavour-breaking expansions in terms of quark masses and charges we determine the leptonic decay constants for the $π^0$ and $η$ mesons, demonstrating in principle how precision determinations of all neutral pseudoscalar decay constants could be reached in lattice QCD with QED and strong isospin-breaking accounted for.

hep-lat↗

arXiv2021

State mixing and masses of the $π^0$, $η$ and $η^\prime$ mesons from $n_f=1+1+1$ lattice QCD+QED

We present a lattice analysis of the light pseudoscalar mesons with consideration for the mixing between the flavour-neutral states $π^0$, $η$ and $η^\prime$. We extract the masses and flavour compositions of the pseudoscalar meson nonet in $n_f=1+1+1$ lattice QCD+QED around an SU(3)-flavour symmetric point, and observe flavour-symmetry features of the extracted data, along with preliminary extrapolation results for the flavour compositions at the physical point. A key result of this work is the observed mass splitting between the $π^0$ and $η$ on our ensembles, which is found to exhibit behaviour that is simply related to the corresponding flavour compositions.

hep-lat↗

arXiv2020

Electromagnetic contribution to $Σ$-$Λ$ mixing using lattice QCD+QED

Mixing in the $Σ^0$-$Λ^0$ system is a direct consequence of broken isospin symmetry and is a measure of both isospin-symmetry breaking as well as general SU(3)-flavour symmetry breaking. In this work we present a new scheme for calculating the extent of $Σ^0$-$Λ^0$ mixing using simulations in lattice QCD+QED and perform several extrapolations that compare well with various past determinations. Our scheme allows us to easily contrast the QCD-only mixing case with the full QCD+QED mixing.

hep-lat↗