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Related papers: Special Symmetric Quark Mass Matrices

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We do a systematic analysis of the question of calculability of CKM matrix elements in terms of quark mass ratios, within the framework of the hypothesis of universality of strength for Yukawa couplings (USY), where all Yukawa couplings…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. C. Branco , D. Emmanuel-Costa , J. I. Silva-Marcos

We investigate the quark masses and mixings by including vector-like down-type quark singlets in universality of strength for Yukawa couplings (USY). In contrast with the standard model with USY, the sufficient $ CP $ violation is obtained…

High Energy Physics - Phenomenology · Physics 2009-11-11 Katsuichi Higuchi , Masato Senami , Katsuji Yamamoto

We show that the quark flavour structure and CP violating phenomena are strongly correlated in supersymmetric theories. For a generic pattern of supersymmetry breaking the two broad categories of Yukawa couplings, democratic and…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. Abel , G. C. Branco , S. Khalil

We analyse the strength of CP violation in an extension of the standard model with an extra $Q=-1/3$ vector-like singlet quark, in the framework of the hypothesis of universality of strength of Yukawa couplings connecting standard quarks.…

High Energy Physics - Phenomenology · Physics 2013-07-02 G. C. Branco , H. R. Colaço Ferreira , A. G. Hessler , J. I. Silva-Marcos

We propose a new mass matrix ansatz: At the grand unified (GU) scale, the standard model (SM) Yukawa coupling matrix elements are integer powers of the square root of the GU gauge coupling constant \varepsilon \equiv…

High Energy Physics - Phenomenology · Physics 2014-11-20 Yong-Chao Zhang , De-Hai Zhang

We study the general dependence of mixing angles on heavy fermion masses when mass hierarchies exist among the fermions. For two generations and small Cabibbo angle, this angle is directly shown to scale like $\mu_1/m_s \pm \mu_2/m_c$,…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Machet , S. T. Petcov

We study the question of calculability of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements within the framework of universal strength for Yukawa couplings (USY). We first classify all solutions leading to $m_u=m_d=0$ within USY and then…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. C. Branco , J. I. Silva-Marcos

We analyse the CP problem in the context of a supersymmetric extension of the standard model with universal strength of Yukawa couplings. A salient feature of these models is that the CP phases are constrained to be very small by the…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. C. Branco , M. E. Gomez , S. Khalil , A. M. Teixeira

We construct a model based on the electroweak gauge group $\rm SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ augmented by an $S_3$ symmetry. We assign nontrivial $S_3$ transformation properties to the quarks and consequently we need two scalar…

High Energy Physics - Phenomenology · Physics 2018-12-12 Dipankar Das , Palash B. Pal

In this work we carry out an exhaustive study to find quark mass matrices in the Standard Model~(SM), with the maximum number of texture zeros consistent with the experimental data. We found four viable configurations of five texture zeros…

High Energy Physics - Phenomenology · Physics 2021-10-13 Yithsbey Giraldo , Eduardo Rojas

Based on the hierarchy exhibited by quarks masses at low energies, we assume that Yukawa couplings of up and down quarks are related by $Y_u\propto Y_d^2$ at grand unification scales. This ansatz gives rise to a symmetrical CKM matrix at…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. González , S. R. Juárez W. , P. Kielanowski , G. López Castro

The predictability of hierarchical quark mass matrices with symmetrically placed texture zeros is explored in the light of current precision measurements on quark masses and mixing data and interesting phenomenological relations among the…

High Energy Physics - Phenomenology · Physics 2017-12-06 Rohit Verma

We analyse the quark mass hierarchy and CKM matrix using the universal Yukawa coupling model with small violations precisely. We estimate the ranges of the values of 8 violation parameters (delta1u, delta2u, delta3u, delta1d, delta2d,…

High Energy Physics - Phenomenology · Physics 2016-09-06 Tadayuki Teshima , Toyokazu Sakai

The condition of unification of gauge couplings in the minimal supersymmetric standard model provides successful predictions for the weak mixing angle as a function of the strong gauge coupling and the supersymmetric threshold scale. In…

High Energy Physics - Phenomenology · Physics 2009-09-25 M. Carena , S. Pokorski , M. Olechowski , C. E. M. Wagner

We show that the observed pattern of quark flavor mixing, such as |V_{us}| \simeq |V_{cd}|, |V_{cb}| \simeq |V_{ts}|, |V_{cd}/V_{td}| \simeq |V_{cs}/V_{ts}| \simeq |V_{tb}/V_{cb}| and |V_{ub}/V_{cb}| < |V_{td}/V_{ts}|, can essentially be…

High Energy Physics - Phenomenology · Physics 2015-06-12 Zhi-zhong Xing

Within a specific texture of the quark mass matrix the notion of a maximal violation of the $CP$ symmetry can be defined. The experimental constraints from weak decays imply that in reality one is close to the case of maximal $CP$…

High Energy Physics - Phenomenology · Physics 2010-11-01 Harald Fritzsch , Zhi-zong Xing

The flavor changing charged currents of the weak sector of the Standard Model are studied in the framework of a quantum statistical approach. The quantum superposition of same-type quarks, generated by the Cabibbo-Kobayashi-Maskawa matrix,…

High Energy Physics - Phenomenology · Physics 2012-06-07 Miguel C. N. Fiolhais

The quark Cabibbo-Kobayashi-Maskawa mixing matrix is a fundamental part of the Standard Model accurately determined to fit world data analysis. In this paper the CKM matrix elements are high accurately rendered via simple compact…

General Physics · Physics 2009-10-12 E. M. Lipmanov

A nearly historical account of quark mass matrix models is given, and the structure of quark mass matrices in the Standard Model is studied. For a minimal parameter basis suggested earlier, where $M_u$ is diagonal and $M_{d11}$, $M_{d13}$,…

High Energy Physics - Phenomenology · Physics 2014-11-17 D. Falcone

We study systematically the possibility for realizing realistic values of quark mass ratios $m_c/m_t$ and $m_s/m_b$ and the mixing angle $V_{cb}$ by using only renormalizable Yukawa couplings derived from heterotic orbifold models. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 Pyungwon Ko , Tatsuo Kobayashi , Jae-hyeon Park
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