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Related papers: New Physics in Flavour Observables

200 papers

Motivated by the measurements of $b\to s\ell^+\ell^-$ transitions, including $R(K)$ and $R(K^*)$, we examine lepton flavour (universality) violation in $B$ decays and its connections to $\mu\to e\gamma$ in generic leptoquark models.…

High Energy Physics - Phenomenology · Physics 2018-02-07 Andreas Crivellin , Dario Mueller , Adrian Signer , Yannick Ulrich

We investigate the consequences of deviations from the Standard Model observed in $b\to s\mu\mu$ transitions for flavour-changing neutral-current processes involving down-type quarks and neutrinos. We derive the relevant Wilson coefficients…

High Energy Physics - Phenomenology · Physics 2020-09-16 Sébastien Descotes-Genon , Svjetlana Fajfer , Jernej F. Kamenik , Martín Novoa-Brunet

The significant divergence between the SM predictions and experimental measurements for the ratios, $R_{D^{(*)}}\equiv \mathcal{B}(\bar{B}\to D^{(*)}\tau^- \bar{\nu}_\tau)/ \mathcal{B}(\bar{B}\to D^{(*)} \ell^{\prime-}…

High Energy Physics - Phenomenology · Physics 2018-10-02 Qin Chang , Jie Zhu , Na Wang , Ru-Min Wang

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

The Standard Model (SM) of particle physics represents our most fundamental knowledge of elementary particles and their interactions. One of the cardinal properties of the SM which has been thoroughly studied during the past years is the…

High Energy Physics - Experiment · Physics 2025-07-16 Sara Celani

The di-leptons and di-neutrinos observed in the final states of flavor-changing neutral b decays provide an ideal platform for probing physics beyond the standard model. Although the latest measurements of $R_{K^{(*)}}$ agree well with the…

High Energy Physics - Phenomenology · Physics 2023-07-10 Nilakshi Das , Rupak Dutta

The discrepancies between $b\to s\ell^+\ell^-$ data and the corresponding Standard Model predictions point to the existence of new physics with a significance at the $5\sigma$ level. While previously a lepton flavour universality violating…

High Energy Physics - Phenomenology · Physics 2023-12-06 Andreas Crivellin , Matthew Kirk

We discuss the modes $B\to K^{(*)}\nu\bar\nu$ in the context of non-standard neutrino interactions that add incoherently to the SM rates. We consider two scenarios: an additional light neutrino; and neutrino lepton flavour violation. We…

High Energy Physics - Phenomenology · Physics 2022-03-04 Xiao Gang He , German Valencia

Rare $K \to \pi \nu \bar \nu$ decays, being dominated by short distance contributions within the Standard Model (SM), open a window for New Physics (NP) searches at low energies. The $ K \to \pi \nu \bar\nu $ branching ratios are expected…

High Energy Physics - Phenomenology · Physics 2022-10-19 S. Fajfer , N. Košnik , L. Vale Silva

The recent successes of the SM do not weaken the arguments in favour of New Physics residing at the TeV scale. Finding and identifying it represents the prime challenge for a generation of high energy physicists. To differentiate between…

High Energy Physics - Phenomenology · Physics 2011-03-23 I. I. Bigi

At Moriond 2019, Belle collaboration has announced new measurements on the flavour ratios $R_D - R_{D^*}$ which are consistent with their Standard Model predictions within $1.2\sigma$. After inclusion of these measurements, the global…

High Energy Physics - Phenomenology · Physics 2021-01-07 Suman Kumbhakar , Ashutosh Kumar Alok , Dinesh Kumar , S. Uma Sankar

The experimental values of the lepton-flavour-universality tests ${\cal R}(D)$ and ${\cal R}(D^*)$ show a tension of about $3.1\sigma$ with their Standard Model prediction. Motivated by this tension, we perform a fit of the $b\to c\tau\nu$…

High Energy Physics - Phenomenology · Physics 2019-07-10 Marta Moscati

The measurements of the ratios $R_{K^{(*)}}$ along with $R_{D^{(*)}}$ hint towards lepton flavor non universality which is in disagreement with the standard model. In this work, we reanalyze the four new physics models, which are widely…

High Energy Physics - Phenomenology · Physics 2019-08-27 Ashutosh Kumar Alok , Jacky Kumar , Dinesh Kumar , Ruchi Sharma

These proceedings review the status of New Physics contributions to flavour violating $B$ decays. The anomalies in charged and neutral current $B$ decays related to lepton flavour universality violation have received a substantial amount of…

High Energy Physics - Phenomenology · Physics 2022-09-21 Monika Blanke

We investigate the implications of the latest LHCb measurement of $R_K$ for NP explanations of the $B$ anomalies. The previous data could be explained if the $b \to s \mu^+ \mu^-$ NP is in (I) $C_{9,{\rm NP}}^{\mu\mu}$ or (II) $C_{9,{\rm…

High Energy Physics - Phenomenology · Physics 2019-08-14 Alakabha Datta , Jacky Kumar , David London

The rare flavour-changing neutral current decay $B_s\to\mu^+\mu^-$ is among the most important indirect probes of new physics at the LHC, as it is strongly suppressed in the Standard Model, very sensitive to new physics effects, and…

High Energy Physics - Phenomenology · Physics 2017-06-07 Wolfgang Altmannshofer , Christoph Niehoff , David M. Straub

The $R(D^{(*)})$ puzzle stands for a $\sim3\sigma$ violation of lepton flavor universality between the decay rates of $B\to D^{(*)}\tau\nu$ and $B\to D^{(*)}\ell\nu$, where $\ell=e,\mu$. If it is accounted for by new physics, there is no…

High Energy Physics - Phenomenology · Physics 2022-08-10 Shikma Bressler , Federico De Vito Halevy , Yosef Nir

Lepton flavour violating (LFV) processes are a smoking gun signal of new physics (NP). If the semileptonic $B$ decay anomalies are indeed due to some NP, such operators can potentially lead to LFV decays involving the second and the third…

High Energy Physics - Phenomenology · Physics 2018-05-16 Zaineb Calcuttawala , Anirban Kundu , Soumitra Nandi , Sunando Kumar Patra

Motivated by recent results by the ATLAS and CMS collaborations on the angular distribution of the $B \to K^* \mu^+\mu^-$ decay, we perform a state-of-the-art analysis of rare $B$ meson decays based on the $b \to s \mu \mu$ transition.…

High Energy Physics - Phenomenology · Physics 2017-06-28 Wolfgang Altmannshofer , Christoph Niehoff , Peter Stangl , David M. Straub

In recent years, several deviations from the Standard Model predictions in semileptonic decays of $B$-meson might suggest the existence of new physics which would break the lepton-flavour universality. In this work, we have explored the…

High Energy Physics - Phenomenology · Physics 2020-05-20 Quan-Yi Hu , Ya-Dong Yang , Min-Di Zheng
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