English
Related papers

Related papers: A New Approach to the Yukawa Puzzle

200 papers

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 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 give a procedure to construct a special class of symmetric quark mass matrices near the democratic limit of equal Yukawa couplings for each sector. It is shown that within appropriate weak-bases, the requirements of symmetry and…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. I. Silva-Marcos

The structure of the Cabibbo-Kobayashi-Maskawa (CKM) matrix is analyzed from the standpoint of a composite model. A model is constructed with three families of quarks, by taking tensor products of sufficient numbers of spin-1/2…

High Energy Physics - Phenomenology · Physics 2009-10-22 Jonathan L. Rosner , Mihir P. Worah

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

A simple ansatz is proposed for neutrino and charged lepton mass matrices, within the framework of universal strength for Yukawa couplings. In this framework all Yukawa couplings have equal moduli and the flavour dependence is only in their…

High Energy Physics - Phenomenology · Physics 2011-03-10 G. C. Branco , M. N. Rebelo , 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

Current experimental data suggest some relations between the Kobayashi-Maskawa Matrix and the quark mass ratios, namely $|V_{us}| \sim \sqrt{m_d / m_s}$, $|V_{ub} / V_{cb}| \sim \sqrt{m_u / m_c}$ and $|V_{cb}| \sim m_s / m_b$. We consider…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Harayama

The one loop Renormalization Group Equations for the Yukawa couplings of quarks are solved. From the solution we find the explicit energy dependence on $t=\ln E/\mu $ of the evolution of the {\em down} quark masses $q=d,s,b$ from the grand…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. R. Juarez W. , S. F. Herrera H. , P. Kielanowski , G. Mora H

We assume the universal Yukawa coupling (democratic mass matrix) with small violations for quarks, charged leptons and neutrinos masses. We could reproduce the mass hierarchy for quark masses and V_{CKM} matrix elements precisely. We adopt…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Teshima , T. Asai

We analyse, within the framework of universal strength for Yukawa couplings (USY), various structures for the Dirac and Majorana neutrino mass matrices giving rise, through the see-saw mechanism, to a degenerate mass spectrum. A specific…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. C. Branco , M. N. Rebelo , J. I. Silva-Marcos

The Standard Model does not constrain the form of the Yukawa matrices and thus the origin of fermion mass hierarchies and mixing pattern remains puzzling. On the other hand, there are intriguing relations between the quark masses and their…

High Energy Physics - Phenomenology · Physics 2024-05-14 Zurab Berezhiani , Benedetta Belfatto

Unitarity triangles and characteristic measurables of the $3\times 3$ Cabibbo-Kobayashi-Maskawa (CKM) matrix are discussed. Beyond the $3\times 3$ CKM scheme we make a rephasing-invariant generalization of the Gronau-Wyler-Dunietz approach…

High Energy Physics - Phenomenology · Physics 2015-06-25 Zhi-zhong Xing

In this paper, we extend the Fritzsch ansatz of quark mass matrices while retaining their hierarchical structures and show that the main features of the Cabibbo-Kobayashi-Maskawa (CKM) matrix $V$, including $|V^{}_{us}| \simeq |V^{}_{cd}|$,…

High Energy Physics - Phenomenology · Physics 2016-06-22 Rohit Verma , Shun Zhou

Building an organized Yukawa structure of quarks and leptons is an essential mission to understand fermion mass hierarchy and flavor mixing in particle physics. Inspired by the similarity of CKM and PMNS mixings, a common mass pattern for…

High Energy Physics - Phenomenology · Physics 2023-11-16 Ying Zhang

Strong gauge and top-Yukawa couplings predicted in the presence of extra dimensions lead to a trickle-down effect of the top-coupling through the renormalization group equations for the quark Yukawa matrices. The matrix elements for the u…

High Energy Physics - Phenomenology · Physics 2007-05-23 Bipin R. Desai , Alexander R. Vaucher

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 have investigated the present renormalization prescriptions of Cabibbo-Kobayashi-Maskawa (CKM) matrix. When considering the prescription which is formulated with reference to the case of zero mixing we find it doesn't satisfy the unitary…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yong Zhou

The evolution of the Cabibbo-Kobayashi-Maskawa matrix and the quark Yukawa couplings is performed for the one-loop renormalization group equations in the universal extra dimension model. It is found that the evolution of mixing angles and…

High Energy Physics - Phenomenology · Physics 2015-03-17 A. S. Cornell , Lu-Xin Liu

In Type-I seesaw model, the lepton flavor mixing matrix (PMNS matrix) and the quark flavor mixing matrix (CKM matrix) may be connected implicitly through a relation between the neutrino Dirac Yukawa coupling $Y_D$ and the quark Yukawa…

High Energy Physics - Phenomenology · Physics 2018-03-21 Naoyuki Haba , Toshifumi Yamada
‹ Prev 1 2 3 10 Next ›