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Related papers: $\eta'$-$\eta_c$-mixing with improved stochastic e…

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We investigate screening masses at both sides of the first order finite temperature transition with 3 quark flavors using the nonperturbatively improved clover fermion action and the Iwasaki gauge action. We have developed the method of…

High Energy Physics - Lattice · Physics 2015-01-27 Xiao-Yong Jin , Yoshinobu Kuramashi , Yoshifumi Nakamura , Shinji Takeda , Akira Ukawa

We propose a chiral quark model including the $\omega$ and $\rho$ meson contributions in addition to the $\pi$ and $\sigma$ meson contributions. We show that the masses of the ground state baryons such as the nucleon, $\Lambda_c$ and…

High Energy Physics - Phenomenology · Physics 2023-06-28 Bing-Ran He , Masayasu Harada , Bing-Song Zou

Mixing of the pseudoscalar mesons is discussed in the quark-flavor basis with the hypothesis that the basis decay constants follow the pattern of particle state mixing. The divergences of the axial vector currents which embody the axial…

High Energy Physics - Phenomenology · Physics 2025-01-22 P. Kroll

Flavor mixing is scrutinized at 1-loop in a SU(2)_L gauge theory of massive fermions. The main issue is to cope with kinetic-like, momentum (p^2) dependent effective interactions that arise at this order. They spoil the unitarity of the…

High Energy Physics - Phenomenology · Physics 2010-06-16 Bruno Machet

We determine mass and flavour content 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 two values…

High Energy Physics - Lattice · Physics 2011-11-16 Konstantin Ottnad , Carsten Urbach , Chris Michael , Siebren Reker

We are computing the modifications for the scalar and pseudoscalar meson masses and mixing angles due to the proper accounting of fermionic vacuum fluctuation in the framework of the generalized 2+1 flavor quark meson model and the Polyakov…

High Energy Physics - Phenomenology · Physics 2013-10-22 Vivek Kumar Tiwari

The interaction between nucleon and charmonia ($J/\psi$ and $\eta_c$) is expected to deepen our understanding of various aspects in nonperturbative QCD ranging from the origin of nucleon mass to $J/\psi$ mass modification in nuclear medium…

High Energy Physics - Lattice · Physics 2025-02-04 Yan Lyu , Takumi Doi , Tetsuo Hatsuda , Takuya Sugiura

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harald Fritzsch , Zhi-zhong Xing

Matrix elements of flavor-diagonal light quark pseudoscalar densities and axial anomaly operators between vacuum and {\eta} and {\eta}' meson states have been determined. This has been done by evaluating current-current correlators of…

High Energy Physics - Phenomenology · Physics 2013-11-01 Janardan Prasad Singh

The effects of intermediate charmed mesons on charmonium transitions with the emission of one pion or eta are studied systematically. Based on a non-relativistic effective field theory we show that charmed meson loops are enhanced compared…

High Energy Physics - Phenomenology · Physics 2011-02-14 Feng-Kun Guo , Christoph Hanhart , Gang Li , Ulf-G. Meißner , Qiang Zhao

The quark-connected leading-order hadronic contributions to the running of the electromagnetic fine structure constant, $\alpha_{\rm QED}$, and the weak mixing angle, $\theta_W$, are determined by a four-flavour lattice QCD computation with…

High Energy Physics - Lattice · Physics 2015-12-09 Florian Burger , Karl Jansen , Marcus Petschlies , Grit Pientka

We investigate topology in lattice simulations of QCD with two flavours of dynamical Wilson fermions. At various sea quark masses we find reasonable agreement between results for the topological charge from fermionic and gluonic…

High Energy Physics - Lattice · Physics 2008-11-26 Gunnar S. Bali , Norbert Eicker , Thomas Lippert , Hartmut Neff , Boris Orth , Klaus Schilling , Thorsten Struckmann , Jochen Viehoff

What flavour structure of $t$-channel thermal dark matter remains compatible with current flavour physics and direct detection bounds? We broadly chart the space of hypotheses using the framework of flavour symmetries and their breaking…

High Energy Physics - Phenomenology · Physics 2026-01-14 Simone Biondini , Admir Greljo , Xavier Ponce Díaz , Alessandro Valenti

This work continues our program of lattice-QCD baryon physics using staggered fermions for both the sea and valence quarks. We present a proof-of-concept study that demonstrates, for the first time, how to calculate baryon matrix elements…

High Energy Physics - Lattice · Physics 2021-03-03 Yin Lin , Aaron S. Meyer , Steven Gottlieb , Ciaran Hughes , Andreas S. Kronfeld , James N. Simone , Alexei Strelchenko

One flavor mass reweighting can be used in lattice QCD computations to fine tune the quark masses to their physical values. We present a new method that utilizes an unbiased stochastic estimation of the one flavor determinant. The…

High Energy Physics - Lattice · Physics 2015-06-16 Jacob Finkenrath , Francesco Knechtli , Björn Leder

We compute the hadronic matrix elements of the four-quark operators relevant for $K^0-{\bar K^0}$ mixing beyond the Standard Model. Our results are from lattice QCD simulations with $n_f=2+1$ flavours of domain-wall fermion, which exhibit…

High Energy Physics - Lattice · Physics 2016-11-08 Nicolas Garron , Renwick J. Hudspith , Andrew T. Lytle

A phenomenological analysis on various decay processes is performed using an energy-dependent $\eta-\eta'$ mixing angle scheme. Special attention is given to the radiative couplings between lowest-lying vector and pseudoscalar mesons. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Escribano , J. M. Frere

Results for the excited meson and baryon spectrum with two flavors of Chirally Improved sea quarks are presented. We simulate several ensembles with pion masses ranging from 250 to 600 MeV and extrapolate to the physical pion mass. Strange…

High Energy Physics - Lattice · Physics 2013-12-03 Georg P. Engel , C. B. Lang , Daniel Mohler , Andreas Schafer

We investigate new-physics contributions to $b\to s \ell\ell$ transitions in the context of an effective field theory extension of the Standard Model, including operator mixing at one loop. We identify the few scenarios where a single…

High Energy Physics - Phenomenology · Physics 2020-02-19 Rupert Coy , Michele Frigerio , Federico Mescia , Olcyr Sumensari

We discuss a mixed-action approach in which sea quarks are regularised using non-perturbatively ${\rm O}(a)$ improved Wilson fermions, while a fully-twisted tmQCD action is used for valence quarks. In this setup, automatic ${\rm O}(a)$…

High Energy Physics - Lattice · Physics 2018-04-18 Gregorio Herdoíza , Carlos Pena , David Preti , José Ángel Romero , Javier Ugarrio