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Related papers: Bounding CKM Mixing with a Fourth Family

200 papers

We review the highlights of quark mixing, particle-antiparticle mixing, CP violation and rare K- and B-decays in the Standard Model. The top quark discovery, the precise measurement of its mass, the improved knowledge of the couplings…

High Energy Physics - Phenomenology · Physics 2016-11-03 Andrzej J. Buras , Robert Fleischer

We obtain constraints on the mixing of vector-like quarks coupling predominantly to the third generation. We consider all (seven) relevant types of vector-like quarks, individually. The constraints are derived from oblique corrections and Z…

High Energy Physics - Phenomenology · Physics 2013-12-10 J. A. Aguilar-Saavedra , R. Benbrik , S. Heinemeyer , M. Perez-Victoria

Neutrino mixing is studied from a symmetry perspective, both bottom-up and top-down. In the bottom-up approach, we start from the tri-bimaximal mixing, or one of its three partial patterns, and construct a list of horizontal symmetry groups…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. S. Lam

In a recent article, this author proposed a program for physics beyond the Standard Model, solely based on modifying the twin pillars of fundamental physics by replacing Lorentz structure with Euclidean Jordan algebra while keeping quantum…

General Physics · Physics 2013-04-12 Guowu Meng

An update profile of the CKM matrix is given, providing numerical and graphical constraints on the CKM parameters in the Standard Model. Constraints on additional parameters accounting for possible new physics contribution in a…

High Energy Physics - Phenomenology · Physics 2009-02-18 Olivier Deschamps

The new quarks of a fourth family are being pushed into the strongly interacting regime due to the lower limits on their masses. The theoretical basis and experimental implications of such quarks are compared with exotic quarks.

High Energy Physics - Phenomenology · Physics 2022-03-02 B. Holdom

The current analysis of the Cabibbo-Kobayashi-Maskawa(CKM) quark mixing matrix uses the standard parametrisation by 3 mixing angles and the CP-violating KM phase. However it would be more convenient to express these mixing angle parameters…

High Energy Physics - Phenomenology · Physics 2011-12-08 T. N. Pham

We investigate the $\epsilon^{\prime} /\epsilon$ for $K\to \pi\pi$ in a sequential fourth generation model. By giving the basic formulae for $\epsilon^{\prime}/\epsilon$ in this model, we analyze the numerical results which are dependent of…

High Energy Physics - Phenomenology · Physics 2019-08-17 Chao-Shang Huang , Wu-Jun Huo , Yue-Liang Wu

Using the experimental result on b\to s\gamma and theoretical result on b\to sg, a four -generation SM is analysed to constrain the rephasing-invariant combinations of the CKM matrix and masses of the fourth generation quarks.

High Energy Physics - Phenomenology · Physics 2009-10-31 T. M. Aliev , D. A. Demir , N. K. Pak

We present a $D_4$ flavored extension of the SM which provides an intuitive reasoning for the masses and mixing patterns in the quark sector. In our model, the Cabibbo mixing angle stems purely from the scalar sector dynamics. In fact, the…

High Energy Physics - Phenomenology · Physics 2022-03-23 Ayushi Srivastava , Miguel Levy , Dipankar Das

An alternative "flipped" version of the quartification model is obtained by rearrangement of the particle assignments. The model has two standard (trinification) families and one flipped quartification family. An interesting…

High Energy Physics - Phenomenology · Physics 2020-09-10 James B. Dent , Thomas W. Kephart , Heinrich Päs , Thomas J. Weiler

We review the historical developments leading to the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix. Present status of the CKM matrix from direct measurements is summarized, giving also the present profile of the unitarity triangle. CP…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Ali , B. Kayser

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

Present limits on chiral fourth-generation quark masses $m_{b'}$ and $m_{t'}$ are broadly generalized and strengthened by combining both $t'$ and $b'$ decays and considering the full range of $t'$ and $b'$ flavor-mixing scenarios (with the…

High Energy Physics - Phenomenology · Physics 2014-11-21 Christian J. Flacco , Daniel Whiteson , Tim M. P. Tait , Shaouly Bar-Shalom

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

Without assuming any specific flavor symmetry and/or any specific mass matrix forms, it is demonstrated that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot obtain the CKM quark mixing matrix $V$ and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yoshio Koide

Models with extended quark sector affect the CP asymmetry in the $B\to \psi K_{S}$ decay, $a_{\psi K_{S}}$, in two ways: First, the top-mediated box diagram is not necessarily the only important contribution to $B-\bar{B}$ mixing. Second,…

High Energy Physics - Phenomenology · Physics 2010-02-03 Galit Eyal , Yosef Nir

The spin-charge-family theory predicts before the electroweak break four - rather than the observed three - massless families of quarks and leptons. The 4 x 4 mass matrices of all the family members demonstrate in this theory the same…

High Energy Physics - Phenomenology · Physics 2015-06-03 G. Bregar , N. S. Mankoc Borstnik

We investigate the possibility to describe the quark mass hierarchies as well as the CKM quark mixing matrix without fine-tuning in a quark flavour model with modular $A_4$ symmetry. The quark mass hierarchies are considered in the vicinity…

High Energy Physics - Phenomenology · Physics 2023-07-26 S. T. Petcov , M. Tanimoto

We derive the canonical form of mixing of the mass eigenstates in the lepto-quark sector of the 4-generation Dirac-Kaehler extension of the SM (DK-SM) [1,2]. The 4 x 4 CKM matrix of DK-SM is expressed in terms two U(2) matrices. It depends…

High Energy Physics - Phenomenology · Physics 2011-03-07 Alexander N. Jourjine