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Related papers: Constraining Fourth Generation with $B\to X_s \gam…

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The paper is devoted to a discussion of general properties of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. First we propose a general method of a recursive construction of the CKM matrix for any number of generations. This allows to set up a…

High Energy Physics - Phenomenology · Physics 2015-02-13 Hilario Pérez , P. Kielanowski , S. R. Juárez W

A 4th generation could be consistent with the recently measured $\Delta m_{B_s}$ as well as ${\cal B}(b\to s\ell^+\ell^-)$, which are SM-like, but generate large $\sin2\Phi_{B_s} \simeq -0.5$ to -0.7. The sign is determined by the hint for…

High Energy Physics - Phenomenology · Physics 2017-08-23 George W. S. Hou

We study the effects of sequential fourth quark generation in rare "B -> K(K*) l^+ l^-" decays induced by "b -> s" transition and in "B_s^0 - bar{B}_s^0" mixing. Using the experimental values on branching ratios of the "B -> X_s gamma" and…

High Energy Physics - Phenomenology · Physics 2009-01-07 T. M. Aliev , A. Ozpineci , M. Savci

The CKM-matrix V is written as a linear combination of the unit matrix I and a matrix U which causes intergenerational-mixing. It is shown that such a V results from a class of quark-mass matrices. The matrix U has to be hermitian and…

High Energy Physics - Phenomenology · Physics 2010-11-23 V. Gupta

In the scenario with four quark generations, we perform a fit using flavor-physics data and determine the allowed values -- preferred central values and errors -- of all of the elements of the 4X4 quark mixing matrix. In addition to the…

High Energy Physics - Phenomenology · Physics 2011-05-12 Ashutosh Kumar Alok , Amol Dighe , David London

In this work, we study possible new contributions to $\epsilon_{K}$ and $\epsilon_{B}$ in the MSSM with large supersymmetric phases. We show that, in the CMSSM, the constrains coming from the experimental measure of the $b \to s \gamma$…

High Energy Physics - Phenomenology · Physics 2011-01-25 O. Vives

Within the Standard model with the 4th generation quarks b' and t' we have analyzed CP-violating flavor changing neutral current processes t -> cX; b'-> sX, b'-> bX,t'-> cX, and t'-> tX, with X=Z,H,gamma,g, by constructing and employing…

High Energy Physics - Phenomenology · Physics 2014-11-20 G. Eilam , B. Melic , J. Trampetic

Using firmly established experimental inputs such as epsilon_K, Delta M_d, Delta M_s, BR(B -> tau nu), gamma, V_cb along with corresponding lattice matrix elements which have been well studied and are in full QCD such as B_K, SU3 breaking…

High Energy Physics - Phenomenology · Physics 2015-05-27 Enrico Lunghi , Amarjiit Soni

Recent results from the DELPHI collaboration led us to review the present bounds on the b' quark mass. We use all available experimental data for m_b' > 96 GeV to constrain the b' quark mass as a function of the Cabibbo-Kobayashi-Maskawa…

High Energy Physics - Phenomenology · Physics 2011-03-23 S. M. Oliveira , R. Santos

We study the decay modes of B_{s}^{0}(\bar{B}_{s}^{0})-->D_{s}^{\pm} K^{\mp}, B_{s}^{0}(\bar{B}_{s}^{0})-->D^{\pm} \pi^{\mp} and B^{0}(\bar{B}^{0})-->D^{\pm} \pi^{\mp} in the perterbative QCD approach based on k_T factorization, including…

High Energy Physics - Phenomenology · Physics 2013-09-25 Xin Yu , Zhi-Tian Zou , Cai-Dian Lu

We study some rare decays of $B_s$ meson governed by the quark level transitions $ b \to s$, in the fourth generation model popularly known as SM4. Recently it has been shown that SM4, which is a simple extension of the SM3, can…

High Energy Physics - Phenomenology · Physics 2013-05-30 R. Mohanta , A. K. Giri

We review several methods for determining the Kobayashi-Maskawa phase $\gamma={\rm Arg} V^*_{ub}$ from rate and CP asymmetry measurements in hadronic B decays. We focus on the processes $B\to DK, B_s\to D_s K$, and on charmless decays to…

High Energy Physics - Phenomenology · Physics 2016-11-23 Michael Gronau

In this review we present and discuss the determination of the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix parameter $V_{cb}$. The CKM matrix parametrizes the weak charged current interactions of quarks in the Standard Model…

High Energy Physics - Phenomenology · Physics 2020-09-29 Giulia Ricciardi , Marcello Rotondo

We extend our recent work and study implications of the Standard Model with four generations (SM4) for rare B and K decays. We again take seriously the several 2-3 $\sigma$ anomalies seen in B, $B_s$ decays and interpret them in the context…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amarjit Soni , Ashutosh Kumar Alok , Anjan Giri , Rukmani Mohanta , Soumitra Nandi

Using existing experimental information from K, B and D decays as well as electroweak precision tests and oblique parameters, we provide constraints and correlations on the parameters of the 4X4 mixing matrix for the Standard Model with…

High Energy Physics - Phenomenology · Physics 2011-07-04 Soumitra Nandi , Amarjit Soni

We present a method of determining weak phase \gamma in the Cabibbo-Kobayashi-Maskawa matrix from decays B->\eta K, \eta' K$ alone. Given a large ratio between color-suppressed and color-allowed tree diagrams extracted from global \pi\pi(K)…

High Energy Physics - Phenomenology · Physics 2009-01-07 Yu-Feng Zhou

The gluino contributions to the $C'_{7,8}$ Wilson coefficients for $b->s \gamma$ are calculated within the unconstrained MSSM. New stringent bounds on the $\delta^{RL}_{23}$ and $\delta^{RR}_{23}$ mass insertion parameters are obtained in…

High Energy Physics - Phenomenology · Physics 2009-11-07 L. Everett , G. L. Kane , S. Rigolin , Lian-Tao Wang , Ting T. Wang

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

We study the decay B\to X_s\gamma in a minimal extension of the standard model with extra up- and down-type quarks whose left- and right-handed components are both SU(2) singlets. Constraints on the extended Cabibbo-Kobayashi-Maskawa matrix…

High Energy Physics - Phenomenology · Physics 2009-10-31 Mayumi Aoki , Eri Asakawa , Makiko Nagashima , Noriyuki Oshimo , Akio Sugamoto

We demonstrate that a vector-like fourth family of quarks induces a genuine chiral enhancement in $b\to s\gamma$, which is absent in the Standard Model (SM). The coexistence of doublet and singlet states allows the chirality flip to occur…

High Energy Physics - Phenomenology · Physics 2026-03-26 Junichiro Kawamura , Yuji Omura