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A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the second and the third family, in agrement with observation. Introducing the mixing between the first and the second family, one finds an interesting…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

We present estimates of light quarks masses using lattice data. Our main results are based on a global analysis of all the published data for Wilson and Staggered fermions, both in the quenched approximation and with $n_f=2$ dynamical…

High Energy Physics - Lattice · Physics 2016-09-01 R. Gupta , T. Bhattacharya

We consider an universal mass matrix model which has a seesaw-invariant structure with the most general texture based on flavor 2 (\leftrightarrow) 3 symmetry common to all quarks and leptons. The CKM quark mixing matrix of the model is…

High Energy Physics - Phenomenology · Physics 2008-12-18 Hiroyuki Nishiura , Koichi Matsuda , Takeshi Fukuyama

The Standard Model predicts a very small CP violation phase $\sin2\Phi^{\rm SM}_{B_s} \simeq -0.04$%= \arg M_{12} \simeq \arg\,(V^*_{ts}V_{tb})^2$ in $B_s$--$\bar B_s$ mixing. %, i.e. of order $\lambda^2\eta$. Any finite value of…

High Energy Physics - Phenomenology · Physics 2014-11-20 W. S. Hou , C. Y. Ma

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}| /…

High Energy Physics - Phenomenology · Physics 2023-06-22 Boris Altshuler

We investigate the implications of a seesaw type mass matrix, i.e., $M_f\simeq m_L M_F^{-1} m_R$, for quarks and leptons $f$ under the assumption that the matrices $m_L$ and $m_R$ are common to all flavors (up-/down- and quark-/lepton-…

High Energy Physics - Phenomenology · Physics 2010-11-01 Y. Koide , H. Fusaoka

In view of the observed strong hierarchy of quark masses, we propose a new description of flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. The necessary and sufficient conditions for…

High Energy Physics - Phenomenology · Physics 2010-11-23 Harald Fritzsch , Zhi-zhong Xing

We determine the renormalization group invariant quark mass corresponding to the sum of the strange and the average light quark mass in the quenched approximation of QCD, using as essential input the mass of the K-mesons. In the continuum…

High Energy Physics - Lattice · Physics 2008-11-26 Joyce Garden , Jochen Heitger , Rainer Sommer , Hartmut Wittig

We show that the scalar sector needed for fermion mass generation when the flavor symmetry of the standard model is maximally gauged can consistently explain two anomalies reported recently by the CDF collaboration - the forward-backward…

High Energy Physics - Phenomenology · Physics 2011-08-08 K. S. Babu , Mariana Frank , Santosh Kumar Rai

We study the phase diagram of a chiral random matrix model with three quark flavors at finite temperature and chemical potential, taking the chiral and diquark condensates as independent order parameters. Fixing the ratio of the coupling…

High Energy Physics - Phenomenology · Physics 2013-05-30 Takashi Sano , Kanako Yamazaki

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. Mass matrix ansatze are considered within the SM and SUSY GUTs where some predictive frameworks based on SU(5) and SO(10) are reviewed. We…

High Energy Physics - Phenomenology · Physics 2009-11-11 N. Chamoun , S. Khalil

We point out that the lower bound on $m_t$ from the CP violation parameter $\epsilon_K$ has increased considerably. Using Wolfenstein parametrization of the CKM matrix we derive an analytic expression for this bound as a function of $\mid…

High Energy Physics - Phenomenology · Physics 2010-11-01 Andrzej J. Buras

The recent results by the Fermilab Lattice and MILC collaborations on the hadronic matrix elements entering $B_{d,s}-\bar B_{d,s}$ mixing show a significant tension of the measured values of the mass differences $\Delta M_{d,s}$ with their…

High Energy Physics - Phenomenology · Physics 2017-02-16 Monika Blanke

We present a non-perturbative determination of the upper and lower Higgs boson mass bounds with a heavy fourth generation of quarks from numerical lattice computations in a chirally symmetric Higgs-Yukawa model. We find that the upper bound…

High Energy Physics - Lattice · Physics 2015-06-12 John Bulava , Karl Jansen , Attila Nagy

We have updated the constraints on flavour universal neutrino self-interactions mediated by a heavy scalar, in the effective 4-fermion interaction limit. We use the relaxation time approximation to modify the collisional neutrino Boltzmann…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-30 Shouvik Roy Choudhury , Steen Hannestad , Thomas Tram

We investigate a flexible method in which we can test the unitarity of the quark flavor mixing matrix step-by-step. Singular-Value-Decomposition (SVD) techniques are used in analyzing the mixing matrix over a broader parameter region than…

High Energy Physics - Phenomenology · Physics 2010-11-23 C. S. Kim , J. D. Kim

Flavor mixing and the quark mass spectrum are intimately related. In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into…

High Energy Physics - Phenomenology · Physics 2009-10-31 Harald Fritzsch

By analogy with an effective model of charged-lepton mass matrix that, with the inputs of $m^{exp}_e $ and $m^{exp}_\mu$, predicts (in a perturbative zero order) $m_\tau = 1776.80 $ MeV close to $m^{exp}_\tau = 1777.03^{+0.30}_{-0.26}$ MeV,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wojciech Krolikowski

We investigate the lepton flavor violation decays, $\tau \to \mu\gamma$, $\tau \to e\gamma$ and $\mu \to e\gamma$, in the framwork of a squential fourth generation model with a heavy fourth neutrino, $\nu'$. Using the recent experimental…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wu-Jun Huo , Tai-Fu Feng

Combining the measured B_s mixing with b \to s\ell^+\ell^- rate data, we find a sizable 4 generation t' quark effect is allowed, for example with m_{t'} \sim 300 GeV and V_{t's}^*V_{t'b} \sim 0.025 e^{\pm i 70^\circ}, which could underly…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wei-Shu Hou , Makiko Nagashima , Andrea Soddu