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Related papers: New Physics in Flavour Observables

200 papers

Recent measurements of $b$-hadron decays show a pattern of consistent tensions with the respective Standard Model (SM) predictions. These tensions appear both in the sector of rare flavour-changing neutral currents and in tree-level…

High Energy Physics - Experiment · Physics 2021-07-13 Johannes Albrecht , Danny van Dyk , Christoph Langenbruch

We analyse the rare processes $K \to \pi\nu\bar\nu$ in view of the recent hints of violations of Lepton Flavour Universality (LFU) observed in B meson decays. If, as suggested by present data, the new interactions responsible for LFU…

High Energy Physics - Phenomenology · Physics 2017-10-25 Marzia Bordone , Dario Buttazzo , Gino Isidori , Joachim Monnard

Recently, the BaBar collaboration reported first evidence for new physics in B->D\tau\nu and B->D*\tau\nu. Combining both processes the significance is 3.4\sigma. This result cannot be explained in a two Higgs doublet model of type II.…

High Energy Physics - Phenomenology · Physics 2013-09-04 Andreas Crivellin , Christoph Greub , Ahmet Kokulu

Motivated by additional experimental hints of Lepton Flavour Universality violation in B decays, both in charged- and in neutral-current processes, we analyse the ingredients necessary to provide a combined description of these phenomena.…

High Energy Physics - Phenomenology · Physics 2017-12-06 Dario Buttazzo , Admir Greljo , Gino Isidori , David Marzocca

We speculate about the possible interpretations of the recently observed excess in the $h \to \tau \mu$ decay. We derive a robust lower bound on the Higgs boson coupling strength to a tau and a muon, even in presence of the most general new…

High Energy Physics - Phenomenology · Physics 2015-10-12 Ilja Dorsner , Svjetlana Fajfer , Admir Greljo , Jernej F. Kamenik , Nejc Kosnik , Ivan Nisandzic

We analyse the new physics implications of theoretically clean $b \to s$ observables in a model-independent approach and compare their coherence with the implications of other rare $B$-decays. A statistical comparison is done between the…

High Energy Physics - Phenomenology · Physics 2021-12-16 T. Hurth , F. Mahmoudi , D. Martinez Santos , S. Neshatpour

Extant anomalies in several semileptonic $B$-meson decays argue for physics beyond the Standard Model. Measurements of both neutral-current decays (such as $R_K$, $R_{K^*}$ and $B_s\rightarrow \phi\mu\mu$) as well as charged-current ones-…

High Energy Physics - Phenomenology · Physics 2019-10-23 Debajyoti Choudhury , Nilanjana Kumar , Anirban Kundu

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

The Littlest Higgs model with T-parity (LHT) contains new sources of flavour and CP violation both in the quark and the lepton sector. They originate from the interactions of ordinary fermions with mirror fermions mediated by new gauge…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Cecilia Tarantino

The exclusive decay mode B ->K*ll has become one of the key players in the search for New Physics in flavor. An increasing number of observables are being studied experimentally, and with increasing precision. Its theoretical description is…

High Energy Physics - Phenomenology · Physics 2013-06-04 Sebastien Descotes-Genon , Tobias Hurth , Joaquim Matias , Javier Virto

I report on investigations of physics beyond the Standard Model using experiments designed to investigate $b$ quark and $c$ quark interactions. Generalized searches involving loop diagrams using heavy meson mixing and CP violation…

High Energy Physics - Phenomenology · Physics 2013-07-02 Sheldon Stone

New neutral heavy gauge bosons ($Z^\prime$) are predicted within many extensions of the Standard Model. While in case they couple to quarks the LHC bounds are very stringent, leptophilic $Z^\prime$ bosons (even with sizable couplings) can…

High Energy Physics - Phenomenology · Physics 2021-06-30 Andrzej J. Buras , Andreas Crivellin , Fiona Kirk , Claudio Andrea Manzari , Marc Montull

The apparent tensions emerging from the comparison of experimental data of the anomalous magnetic moments of the muon and electron to the Standard Model predictions ($\Delta a_{\mu,e}$) could be interpreted as a potential signal of New…

High Energy Physics - Phenomenology · Physics 2022-10-18 J. Kriewald , J. Orloff , E. Pinsard , A. M. Teixeira

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 RK measurement by LHCb suggests non-standard lepton-universality violation (LUV) to occur in b to s l+ l- decays, with effects in muons rather than electrons. It is intriguing that a number of other measurements of b to s l+ l-…

High Energy Physics - Phenomenology · Physics 2017-08-29 Diego Guadagnoli

The search for New Physics (NP) beyond the Standard Model (SM) has been a central focus of particle physics, including in the context of $B$-meson decays involving $b \to s \ell \ell$ transitions. These transitions, mediated by…

High Energy Physics - Phenomenology · Physics 2024-08-08 F. Mahmoudi , Y. Monceaux

Flavour Changing Neutral Current (FCNC) decays are forbidden at lowest perturbative order in the Standard Model (SM) and only allowed via quantum loops. These transitions are therefore heavily suppressed in the SM, and New Physics (NP) can…

High Energy Physics - Experiment · Physics 2026-05-19 Christoph Langenbruch

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 discuss the implications of $b \to s \ell^+\ell^-$ measurements and their deviations with respect to the Standard Model predictions in a model-independent framework. We highlight in particular the impact of the recent updated…

High Energy Physics - Phenomenology · Physics 2022-10-14 T. Hurth , F. Mahmoudi , D. Martinez Santos , S. Neshatpour

Several experiments have measured a deviation in $B\to D^{(*)}$ semileptonic decays, that point to new physics at the TeV scale violating lepton flavor universality. A scalar leptoquark $S_1$, with a suitable structure of couplings in…

High Energy Physics - Phenomenology · Physics 2024-05-28 Leandro Da Rold