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Related papers: Lessons for new physics from CKM studies

200 papers

The CKM matrix and its unitarity is analyzed by disentangling experimental information obtained from three different particle systems of neutrons, mesons, and nuclei. New physics beyond the Standard Model is supported under the new…

General Physics · Physics 2020-09-04 Wanpeng Tan

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 a large class of models, the only significant new physics effect on the CP asymmetries in $B \to \psi K_S$ and $B \to \pi\pi$ decays is a new contribution to the $B-\bar B$ mixing amplitude. This allows a model independent construction…

High Energy Physics - Phenomenology · Physics 2010-11-23 Yuval Grossman , Yosef Nir , Mihir P. Worah

The Cabibbo-Cobayashi-Maskawa (CKM) matrix parametrizes the misalignement between the up- and down-quark mass basis in the Standard Model (SM). The observation of first row CKM unitarity violation has recently emerged as a new anomaly of…

High Energy Physics - Phenomenology · Physics 2021-11-09 Claudio Andrea Manzari

We explore the possibility of using CP violation in B decays to detect the presence of physics beyond the Standard Model. We first study the possibility of new physics in the $B-\bar B$ mixing amplitude. We discuss a construction to extract…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mihir P. Worah

Recent high precision determinations of $V_{us}$ and $V_{ud}$ indicate towards anomalies in the first row of the CKM matrix. Namely, determination of $V_{ud}$ from superallowed beta decays and of $V_{us}$ from kaon decays imply a violation…

High Energy Physics - Phenomenology · Physics 2021-10-27 Benedetta Belfatto , Zurab Berezhiani

We update the constraints on new-physics contributions to Delta F=2 processes from the generalized unitarity triangle analysis, including the most recent experimental developments. Based on these constraints, we derive upper bounds on the…

We confront the recent improved measurements of the D_{(s)} (semi) leptonic decays with lattice QCD (LQCD) with n_f=3 flavours and QCD spectral sum rules (QSSR) predictions. D\to\mu\nu_\mu leptonic width data compared with theoretical…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stephan Narison

The SM unitarity triangle (UT) is completely determined by the parameters $\gamma$ and $|V_{ub}|$ which can be extracted from tree-level processes and are assumed to be free of new physics. By comparison with other determinations of UT…

High Energy Physics - Phenomenology · Physics 2007-05-23 Patricia Ball

We analyse the present experimental evidence for a complex CKM matrix, even allowing for New Physics contributions to $\epsilon_{K}$, $a_{J/\Psi K_{S}}$%, $\Delta M_{B_{d}}$, $\Delta M_{B_{s}}$, and the $\Delta I=1/2$ piece of $% B\to \rho…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. J. Botella

We reemphasize that the ratio $R_{s\mu} \equiv \overline{\mathcal{B}}(B_s\to\mu\bar\mu)/\Delta M_s$ is a measure of the tension of the Standard Model (SM) with latest measurements of $\overline{\mathcal{B}}(B_s\to\mu\bar\mu)$ that does not…

High Energy Physics - Phenomenology · Physics 2021-11-18 Christoph Bobeth , Andrzej J. Buras

We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a…

High Energy Physics - Phenomenology · Physics 2016-07-20 Ben Gripaios , M. Nardecchia , S. A. Renner

Recent experimental measurements and lattice QCD calculations are now reaching the precision (and accuracy) needed to over-constrain the CKM parameters $\bar\rho$ and $\bar\eta$. In this brief review, I discuss the current status of lattice…

High Energy Physics - Phenomenology · Physics 2009-11-11 Matthew Wingate

The recent measurements on $R_D$, $R_{D^*}$ and $R_{J/\psi}$ by three pioneering experiments, BaBar, Belle and LHCb, indicate that the notion of lepton flavour universality is violated in the weak charged-current processes, mediated through…

High Energy Physics - Phenomenology · Physics 2021-08-06 Aishwarya Bhatta , Atasi Ray , Rukmani Mohanta

The latest fits to the CKM matrix indicate that alpha=(90.7+4.5-2.9) degrees. The proximity of alpha to a right-angle raises the question: is it merely accidental or is it due to some physics beyond the Standard Model? In the framework of…

High Energy Physics - Phenomenology · Physics 2009-04-21 P. F. Harrison , D. R. J. Roythorne , W. G. Scott

Kaon physics can test new-physics effects in leptonic or semileptonic decays. A unitarity test of the first row of the CKM mixing matrix is obtained from the precision measurements of Kl3 widths for K{\pm}, KL, and (unique to KLOE) KS. The…

High Energy Physics - Experiment · Physics 2022-03-02 B. Sciascia

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

Flavour physics offers interesting probes for the exploration of the Standard Model and the search for new physics. In these lectures, we focus on B- and K-meson decays, introduce the concept of low-energy effective Hamiltonians to describe…

High Energy Physics - Phenomenology · Physics 2016-11-09 Robert Fleischer

We give a comprehensive account of the flavour physics of Beyond-Standard-Model (BSM) effects in $b \to c \bar{c} s$ transitions, considering the full set of 20 four-quark operators. We discuss the leading-order structure of their RG mixing…

High Energy Physics - Phenomenology · Physics 2023-07-13 S. Jäger , M. Kirk , A. Lenz , K. Leslie

We propose a minimal extension of the Standard Model where an up-type vector-like quark, denoted $T$, is introduced and provides a simple solution to the CKM unitarity problem. We adopt the Botella-Chau parametrization in order to extract…

High Energy Physics - Phenomenology · Physics 2022-05-24 Francisco J. Botella , G. C. Branco , M. N. Rebelo , J. I. Silva-Marcos , José Filipe Bastos