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Related papers: Lessons for new physics from CKM studies

200 papers

Recently, several indications of lepton non-universality observables have been perceived in semileptonic $B$ meson decay processes, both in the neutral-current ($b \to s ll $) and charged-current ($b \to c l \bar \nu_l$) transitions.…

High Energy Physics - Phenomenology · Physics 2025-07-16 Aishwarya Bhatta , Rukmani Mohanta

The availability of high-intensity kaon beams at the J-PARC Hadron Experimental Facility and the CERN SPS North Area, together with the abundant forward production of kaons at the LHC, gives rise to unique possibilities for sensitive tests…

High Energy Physics - Experiment · Physics 2022-04-29 The KOTO , LHCb , NA62/KLEVER Collaborations , the US Kaon Interest Group

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles, it is argued that the description of flavor mixing must take this into account. One particularly interesting way to describe the flavor…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harald Fritzsch

CKM-unitarity, direct and indirect CP-violation and the \Delta I=1/2 rule in full lattice QCD are the focus of this talk. To this end I will discuss and compare recent lattice results for leptonic, semi-leptonic and non-leptonic decays of…

High Energy Physics - Lattice · Physics 2009-04-14 Andreas Juttner

Theoretical and computational advances in lattice calculations are reviewed, with focus on examples relevant to the unitarity triangle of the CKM matrix. Recent progress in semi-leptonic form factors for B -> pi l nu and B -> D* l nu, as…

High Energy Physics - Phenomenology · Physics 2010-11-23 Andreas S. Kronfeld

We perform a combined analysis of $B \to \pi \pi$ and $B \to \pi K$ decays with the current experimental data. Assuming SU(3) flavor symmetry and no new physics contributions to the topological amplitudes, we demonstrate that the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Seungwon Baek

The B_s to mu+ mu- decay plays an outstanding role in tests of the Standard Model and physics beyond it. The LHCb collaboration has recently reported the first evidence for this decay at the 3.5 sigma level, with a branching ratio in the…

High Energy Physics - Phenomenology · Physics 2014-12-19 Andrzej J. Buras , Robert Fleischer , Jennifer Girrbach , Robert Knegjens

I review recent progresses in heavy quarks physics on the lattice. I focus on decay constants and form factors relevant for the extraction of CKM matrix elements from experimental data. B-\bar{B} mixing is also discussed. In the last part…

High Energy Physics - Lattice · Physics 2009-01-06 Michele Della Morte

Using HISQ $N_f=2+1+1$ MILC ensembles with five different values of the lattice spacing, including four ensembles with physical quark masses, we have performed the most precise computation to date of the $K\to\pi\ell\nu$ vector form factor…

The most recent measurements of the observables $R_{D^{(*)}}$ are in tension with the Standard Model offering hints of New Physics in $b\rightarrow c \ell \bar{\nu}_{\ell}$ transitions. Motivated by these results, in this work we present an…

High Energy Physics - Phenomenology · Physics 2018-12-14 Giovanni Banelli , Robert Fleischer , Ruben Jaarsma , Gilberto Tetlalmatzi-Xolocotzi

In contrast with $B^0-\bar B^0$, $B_s-\bar B_s$ mixing where the standard model (SM) contributions overwhelm that of new physics beyond standard model (BSM), a measured relatively large $D^0-\bar D^0$ mixing where the SM contribution is…

High Energy Physics - Phenomenology · Physics 2015-06-18 Lian-Bao Jia , Ming-Gang Zhao , Hong-Wei Ke , Xue-Qian Li

We present an updated and improved global fit analysis of current flavor and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active…

Motivated by the possibility of the low value of sin2\beta in the measurements of BABAR and BELLE collaborations, we have explored the possibilty of construction of reference unitarity triangle using the unitarity of the CKM matrix, the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Monika Randhawa , Manmohan Gupta

Recently, the LHCb Collaboration provided updated measurements for the lepton flavour ratios $R_K$ and $R_{K^*}$. The currently observed values align with the predictions of the standard model. In light of these recent updates, our…

High Energy Physics - Phenomenology · Physics 2024-10-04 Juhi Vardani , Ria Sain

We study predictions for B-physics in a class of models, recently introduced, with a non-supersymmetric warped extra dimension. In these models few ($\sim 3$) TeV Kaluza-Klein masses are consistent with electroweak data due to bulk…

High Energy Physics - Phenomenology · Physics 2010-04-06 Kaustubh Agashe , Gilad Perez , Amarjit Soni

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

In supersymmetric grand-unified models, the lepton mixing matrix can possibly affect flavor-changing transitions in the quark sector. We present a detailed analysis of a model proposed by Chang, Masiero and Murayama, in which the…

High Energy Physics - Phenomenology · Physics 2015-05-27 Jennifer Girrbach , Sebastian Jager , Markus Knopf , Waldemar Martens , Ulrich Nierste , Christian Scherrer , Soren Wiesenfeldt

Tests of lepton-universality as rate ratios in $b\to s \ell\ell$ transitions can be predicted very accurately in the Standard Model. The deficits with respect to expectations reported by the LHCb experiment in muon-to-electron ratios of the…

High Energy Physics - Phenomenology · Physics 2020-02-03 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Jorge Martin Camalich , Xiu-Lei Ren , Rui-Xiang Shi

SU(3) gauge theories with increasing number of light fermions are the templates of strongly interacting sectors and studying their low-energy dynamics and spectrum is important, both for understanding the strong dynamics of QCD itself, but…

We analyze the possibility of having new physics effects in the decay rate difference, $\Delta \Gamma_d$, of neutral $B_d$ mesons. Three different sources of enhancement are considered, CKM unitarity violations, beyond standard model…

High Energy Physics - Phenomenology · Physics 2015-01-09 Gilberto Tetlalmatzi-Xolocotzi