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Related papers: New Physics bounds from CKM-unitarity

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$B$ decays proceeding via $b\to c\ell\nu$ transitions with $\ell=e$ or $\mu$ are tree-level processes in the Standard Model. They are used to measure the CKM element $V_{cb}$, as such forming an important ingredient in the determination of…

High Energy Physics - Phenomenology · Physics 2019-01-30 Martin Jung , David M. Straub

We propose a set of precision muon-related observables that serve as a tool to constrain new physics models. Using LEP's precision measurements on the $Z$-boson pole, we derive bounds on the new physics quantum contributions to the decay $Z…

High Energy Physics - Phenomenology · Physics 2023-10-11 Gabriel Lourenço , André Milagre , Rui Santos , João P. Silva

In this work we investigate the implication of low-energy precision measurements on the quark-lepton charged currents in general neutrino interactions with sterile neutrinos in effective field theories. The physics in low-energy…

High Energy Physics - Phenomenology · Physics 2020-12-02 Tong Li , Xiao-Dong Ma , Michael A. Schmidt

Recent experimental and theoretical results on kaon semileptonic decays have significantly improved the determination of the CKM matrix element V_us. After briefly summarizing the impact of the new experimental determinations, I will…

High Energy Physics - Phenomenology · Physics 2007-05-23 Vittorio Lubicz

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

This talk highlights, from a theoretical point of view, some recent exciting results in flavor physics, as well as future prospects. We discuss possible implications of a subset of the experimental results in tension with the standard…

High Energy Physics - Phenomenology · Physics 2016-06-21 Zoltan Ligeti

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 explore CP-violating (CPV) effects of heavy New Physics in flavour-changing quark dipole transitions, within the framework of Standard Model Effective Field Theory (SMEFT). First, we establish the relevant dimension six operators and…

High Energy Physics - Phenomenology · Physics 2023-06-30 Svjetlana Fajfer , Jernej F. Kamenik , Nejc Košnik , Aleks Smolkovič , Michele Tammaro

The muon is playing a unique role in sub-atomic physics. Studies of muon decay both determine the overall strength and establish the chiral structure of weak interactions, as well as setting extraordinary limits on…

High Energy Physics - Experiment · Physics 2015-06-05 T. P. Gorringe , D. W. Hertzog

Measurements of angular correlations in nuclear beta decay are important tests of the Standard Model (SM). Among those, the so-called D correlation parameter occupies a particular place because it is odd under time reversal, and because the…

High Energy Physics - Phenomenology · Physics 2023-01-04 Adam Falkowski , Antonio Rodríguez-Sánchez

We use rigorous QCD dispersion relations to derive model-independent bounds on the B -> pi l nu, D -> pi l nu and D -> K l nu form factors. These bounds are particularly restrictive when the value of the observable form factor at one or…

High Energy Physics - Phenomenology · Physics 2010-11-01 C. Glenn Boyd , Benjamin Grinstein , Richard F. Lebed

The angles of the CKM unitarity triangle are now known well enough to allow a determination of its sides from global fits, with good accuracy. Assuming that new physics does not affect the angles, UTfit and CKMfitter find $|V_{ub}| =…

High Energy Physics - Phenomenology · Physics 2008-11-26 Patricia Ball

The continued interest in placing bounds on the neutron's Electric Dipole Moment (EDM) is due to the implications regarding the characteristics of the strong interaction and, in particular, its behavior under the CP symmetry. In this work,…

High Energy Physics - Phenomenology · Physics 2024-11-26 Octavio Guerrero , Libertad Barrón-Palos , Daniel Sudarsky

Recent experimental results of ${\cal R}(D^{(*)})$ deviate from the standard model (SM) by $3.1\sigma$, suggesting a new physics (NP) that affects the $b\to c \tau \bar\nu_\tau$ transition. Motivated by this, we investigate the possible NP…

High Energy Physics - Phenomenology · Physics 2019-12-18 Xiao-Long Mu , Ying Li , Zhi-Tian Zou , Bin Zhu

We briefly report on some particular aspects of new physics searches concerning, on the one side, the CKM paradigm and, on the other, the global fit to rare $b\to s \ell\ell$ observables including lepton flavour universality ones. We put…

High Energy Physics - Phenomenology · Physics 2017-11-13 Joaquim Matias

We analyze the decays $K\to\pi\ell\nu$ and $P\to\ell\nu$ ($P=K,\pi$, $\ell=e,\,\mu$) using a low-energy Effective-Field-Theory approach to parametrize New Physics and study the complementarity with baryon $\beta$ decays. We then provide a…

High Energy Physics - Phenomenology · Physics 2017-02-01 Martín González-Alonso , Jorge Martin Camalich

Recently several measurements in the neutral current sector $b\rightarrow s l^+l^-$ ($l=e$ or $\mu$) as well as in the charged current sector $b \rightarrow c \tau \bar{\nu}$ show significant deviations from their Standard Model…

High Energy Physics - Phenomenology · Physics 2019-05-22 Suman Kumbhakar , Jyoti Saini

We present a technique to determine the scale of New Physics (NP) compatible with any set of data, relying on well-defined credibility intervals. Our approach relies on the statistical view of the effective field theory capturing New…

High Energy Physics - Phenomenology · Physics 2015-06-16 Sylvain Fichet

The rare decay $B^0_s \to \mu^+\mu^-$ plays a key role for the testing of the Standard Model. It is pointed out that the sizable decay width difference $\Delta\Gamma_s$ of the $B_s$-meson system affects this channel in a subtle way. As a…

High Energy Physics - Phenomenology · Physics 2014-08-26 Robert Fleischer

At present, the main topics addressed by kaon physics are the unitarity test of CKM matrix via precision measurements of the Cabibbo angle as well as precision tests of discrete symmetries: in particular, study of possible CPT violations in…

High Energy Physics - Experiment · Physics 2007-05-23 B. Sciascia