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Related papers: $\varepsilon'/\varepsilon$ in 331 Models

200 papers

The Standard Model (SM) does not contain by definition any new physics (NP) contributions to any observable but contains four CKM parameters which are not predicted by this model. We point out that if these four parameters are determined in…

High Energy Physics - Phenomenology · Physics 2024-01-05 Andrzej J. Buras

Despite the observation of significant suppression of $b\to s\mu^+\mu^-$ branching ratios no clear sign of New Physics (NP) has been identified in $\Delta F=2$ observables, in particular to $\varepsilon_K$. Assuming negligible NP…

High Energy Physics - Phenomenology · Physics 2023-05-24 Jason Aebischer , Andrzej J. Buras , Jacky Kumar

Meson and anti-meson mixing processes constitute an important source of constraints on models that give tree level contributions to flavor violating neutral processes. In electroweak $ \text{SU}(3)_\text{L} \times \text{U}(1)_N $ models,…

High Energy Physics - Phenomenology · Physics 2023-10-03 Vinícius Oliveira , C. A. de S. Pires

We investigate in detail the flavor structure of the minimal 331 model and its implications for several flavor changing neutral current (FCNC) processes. In this model, where the weak SU(2)_L gauge group of the Standard Model is extended to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christoph Promberger , Sebastian Schatt , Felix Schwab

Following the 1999 analysis of Gambino, Haisch and one of us, we stress that all the recent NLO analyses of $\varepsilon'/\varepsilon$ in the Standard Model (SM) suffer from the renormalization scheme dependence present in the electroweak…

High Energy Physics - Phenomenology · Physics 2020-01-29 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras

The most important hint of physics beyond the Standard Model (SM) from the 1995 precision electroweak data is that the most precisely measured quantities, the total, leptonic and hadronic decay widths of the $Z$ and the effective weak…

High Energy Physics - Phenomenology · Physics 2010-11-23 Kaoru Hagiwara

Flavor-changing neutral current decays such as $b \to s \bar{\ell} \ell$ are highly suppressed in the Standard Model (SM) and therefore provide sensitive tests for new physics. Persistent tensions between SM predictions and experimental…

High Energy Physics - Phenomenology · Physics 2025-10-22 Arianna Tinari

We analyse the possible presence of New Physics (NP) in the Flavour Sector and evaluate its potential for solving the tension between the experimental values of $\AJPKs$ and $\BTNu$ with respect to the Standard Model (SM) expectations.…

High Energy Physics - Phenomenology · Physics 2015-06-05 F. J. Botella , G. C. Branco , M. Nebot

Precision measurements of rare particle physics phenomena (flavor oscillations and decays, electric dipole moments, etc.) are often sensitive to the effects of new physics encoded in higher-dimensional operators with Wilson coefficients…

High Energy Physics - Phenomenology · Physics 2015-10-12 Matthias Le Dall , Maxim Pospelov , Adam Ritz

The Glashow-Iliopoulos-Maiani mechanism is extremely efficient to suppress the flavour-changing neutral current decays of charmed hadrons induced by the $c \to u$ transitions, making such processes particularly sensitive to phenomena beyond…

High Energy Physics - Phenomenology · Physics 2022-01-05 Pietro Colangelo , Fulvia De Fazio , Francesco Loparco

The rare four-fold decay $B_s \to K^*(\to K\pi)\mu^+\mu^- $, governed by the flavor-changing neutral current transition $b \to d\mu^+\mu^-$, provides a sensitive probe for testing the Standard Model (SM) and investigating signatures of new…

High Energy Physics - Phenomenology · Physics 2026-05-12 Zohaib Aarfi , Qazi Maaz Us Salam , Ishtiaq Ahmed , Faisal Munir Bhutta , Rizwan Khalid , M. Ali Paracha

The experimental studies of the observables associated with the $b \rightarrow c$ transitions in the semileptonic $B-$ meson decays at BaBar, Belle and LHCb have shown some deviations from the Standard Model (SM) predictions, consequently,…

High Energy Physics - Phenomenology · Physics 2024-06-24 Tahira Yasmeen , Ishtiaq Ahmed , Saba Shafaq , Muhammad Arslan , Muhammad Jamil Aslam

A flavor-dependent model (FDM) is proposed in this work. The model extends the Standard Model by an extra $U(1)_F$ local gauge group, two scalar doublets, one scalar singlet and two right-handed neutrinos, where the additional $U(1)_F$…

High Energy Physics - Phenomenology · Physics 2024-05-29 Jin-Lei Yang , Hai-Bin Zhang , Tai-Fu Feng

In this work we overhaul previous studies of Flavor Changing Neutral Current processes in the context of the Reduced Minimal 3-3-1 model(RM331). We sift the individual contributions from the CP even scalars and the $Z^{\prime}$ gauge boson…

High Energy Physics - Phenomenology · Physics 2015-06-18 D. Cogollo , Farinaldo S. Queiroz , P. Vasconcelos

The simplest extension of the SM that generally introduces new sources of flavour and CP violation as well as right-handed currents is the addition of a U(1) gauge symmetry to the SM gauge group. If the corresponding heavy gauge boson Z'…

High Energy Physics - Phenomenology · Physics 2013-03-01 Andrzej J. Buras , Fulvia De Fazio , Jennifer Girrbach

The decays $K^+\to\pi^+\nu\bar\nu$ and $K_L\to\pi^0\nu\bar\nu$, being the theoretically cleanest rare decays of mesons, are very sensitive probes of New Physics. In view of the excellent prospects of reaching the Standard Model sensitivity…

High Energy Physics - Phenomenology · Physics 2015-12-10 Andrzej J. Buras , Dario Buttazzo , Robert Knegjens

During the last four years several parameters relevant for the analysis of the CP-violating ratio epsilon'/epsilon improved and/or changed significantly. In particular, the experimental value of epsilon'/epsilon and the strange quark mass…

High Energy Physics - Phenomenology · Physics 2009-11-10 Andrzej J. Buras , Matthias Jamin

The CP violation parameter $Re(\epsilon'/\epsilon)$ has previously been calculated in the standard model and the result depends on the top quark mass in an exciting way. We consider how the result is modified in two specific extensions of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paul H. Frampton

We discuss the supersymmetric contribution to $\epsilon'/\epsilon$ in various supersymmetric flavor models. We find that in alignment models the supersymmetric contribution could be significant while in heavy squark models it is expected to…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Eyal , A. Masiero , Y. Nir , L. Silvestrini

We have considered a general 5D warped model with SM fields propagating in the bulk and computed explicit expressions for oblique and non-oblique electroweak observables as well as for flavor and CP violating effective four-fermion…

High Energy Physics - Phenomenology · Physics 2015-05-30 Joan A. Cabrer , Gero von Gersdorff , Mariano Quiros