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Related papers: Mixing with vector-like quarks: constraints and ex…

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A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the secons and the third family, in agreement 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 propose a mass matrix model that gives a unified description of quark and lepton with the same texture form based on a flavor 2 <-> 3 symmetry. The model is in contrast with the conventional picture that the mass matrix forms in the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Koichi Matsuda , Hiroyuki Nishiura

We consider the minimal extension of the Standard Model with three generations of massive neutrinos that mix. We then determine the parameters of the model that satisfy all experimental constraints.

High Energy Physics - Experiment · Physics 2016-08-15 B. Hoeneisen , C. Marín

We present an extra condition by which the size of the uncertainty associated with the diagonal elements in the quark mixing matrix can be further constrained when the matrix is parameterized by a combination of three mixing angles and a…

High Energy Physics - Phenomenology · Physics 2025-09-11 Jae Jun Kim

We calculate the contributions of the vector-like quark model to $\BsBs$ mixing, taking into account the constraints from the decay $B\to X_s\gamma$. In this model the neutral bosons mediate flavor-changing interactions at the tree level.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Mayumi Aoki , Gi-Chol Cho , Makiko Nagashima , Noriyuki Oshimo

Against the conventional picture that the mass matrix forms in the quark sectors will take somewhat different structures from those in the lepton sectors, a possibility that all the mass matrices of quarks and leptons have the same form as…

High Energy Physics - Phenomenology · Physics 2017-08-23 Yoshio Koide , Hiroyuki Nishiura , Koichi Matsuda , Tatsuru Kikuchi , Takeshi Fukuyama

Starting with the hypothesis that quark and lepton mixings are identical at or near the GUT scale, we show that the large solar and atmospheric neutrino mixing angles together with the small reactor angle $U_{e3}$ can be understood purely…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. N. Mohapatra , M. K. Parida , G. Rajasekaran

The standard model extended with the pairs of the vector-like families is studied. The model independent analysis for an arbitrary case and an explicit realization for the case with one pair of the heavy vector-like families are considered.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. F. Pirogov , O. V. Zenin

A mechanism to have the quark mass hierarchy in the supersymmetric composite model is proposed. The source of the hierarchy is the kinetic-term mixing between composite quarks. Such mixing can be expected, if quarks are composite particles.…

High Energy Physics - Phenomenology · Physics 2009-10-31 Noriaki Kitazawa

We propose a model of generations that has exactly three generations. This model has several attractive features: There is a simple mechanism to produce the CKM quark mixings and their neutrino analogs. There are definite predictions for…

High Energy Physics - Phenomenology · Physics 2007-05-23 O. W. Greenberg

It is proposed that all flavor mixing is caused by the mixing of the three quark and lepton families with vectorlike fermions in 5 + 5-bar multiplets of SU(5). This simple assumption implies that both V_{CKM} and U_{MNS} are generated by a…

High Energy Physics - Phenomenology · Physics 2015-06-11 S. M. Barr , Heng-Yu Chen

We investigate the pair production of a vector-like quark triplet with hypercharge 5/3 decaying into top quark and a complex scalar triplet with hypercharge 1 at the LHC. This novel scenario, featuring particles with exotic charges - two…

High Energy Physics - Phenomenology · Physics 2024-07-12 Avik Banerjee , Venugopal Ellajosyula , Luca Panizzi

The $D_4$ flavor model based on $\mathrm{SU}(3)_C \otimes \mathrm{SU}(3)_L \otimes \mathrm{U}(1)_X$ gauge symmetry that aims at describing quark mass and mixing is updated. After spontaneous breaking of flavor symmetry, with the constraint…

High Energy Physics - Phenomenology · Physics 2015-07-30 V. V. Vien , H. N. Long

We emphasise that even in the extreme chiral limit where only the top and bottom quarks acquire mass, quark mixing is physically meaningful. This implies that the natural value of $|V_{13}|^2 + |V_{23}|^2$ is of order one, which is to be…

High Energy Physics - Phenomenology · Physics 2018-06-08 F. J. Botella , G. C. Branco , M. Nebot , M. N. Rebelo , J. I. Silva-Marcos

Several lines of reasoning suggest that there might exist a non-sequential fourth generation of heavy quarks having very small mixing with light quarks and hence exceptionally long lifetime.

High Energy Physics - Phenomenology · Physics 2009-10-30 Paul H. Frampton , Pham Quang Hung

Models with new vector-like quarks can produce observable quark mixing effects which are forbidden in the Standard Model. We classify all such models and write down the effective Lagrangian that results from integrating out the new quarks.…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. del Aguila , M. Perez-Victoria , J. Santiago

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

The mass relations among respective quark family members are predicted and similar mass relation for the lepton family member are obtained. The volume of the volume element is also calculated which is (3/2)^(1/2).

High Energy Physics - Phenomenology · Physics 2007-05-23 Amjad Hussain Shah Gilani

Vector-like quarks, usually dubbed top partners, are a common presence in composite Higgs models. Being composite objects, their mass is expected to be of the order of their inverse size, that is the condensation scale of the new strong…

High Energy Physics - Phenomenology · Physics 2016-05-06 Giacomo Cacciapaglia , Alberto Parolini

The mixing of three and four massive neutrinos is considered. It is shown that the neutrino oscillation data are not compatible with a hierarchy of couplings in the three-neutrino case. In the case of four neutrinos, a hierarchy of masses…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. M. Bilenky , C. Giunti , W. Grimus