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Related papers: Testing the $R_{D^{(*)}}$ Anomaly at the LHeC

200 papers

Recent searches for a first-generation leptoquark by the CMS collaboration have shown around 2.5 sigma deviations from Standard Model predictions in both the eejj and e nu jj channels. Furthermore, the eejj invariant mass distribution has…

High Energy Physics - Phenomenology · Physics 2015-05-20 Yang Bai , Joshua Berger

We confront the malaphoric $B_3-L_2$ model with bounds coming from a search for resonances in the di-lepton channels at the 13~TeV LHC. In contrast to the original $B_3-L_2$ model, the $Z^\prime$ of the malaphoric $B_3-L_2$ model has…

High Energy Physics - Phenomenology · Physics 2024-12-04 Ben Allanach

The current discrepancy in $R_{D^{(*)}}=BR(\bar{B} \to D^{(*)}\tau\bar{\nu})/BR(\bar{B}\to D^{(*)} \ell \bar{\nu})$ where $\ell=e,\,\mu$ may imply a know particle with the mass around the order of TeV. Therefore it is well motivated to test…

High Energy Physics - Phenomenology · Physics 2022-06-10 Syuhei Iguro

We discuss a model that can accommodate the $B$-physics anomalies, based on combining two scalar leptoquarks, $R_2$ and $S_3$, of mass $\mathcal{O}(1\,\mathrm{TeV})$, and that we proposed in our previous paper. We update the analysis of its…

High Energy Physics - Phenomenology · Physics 2022-06-22 Damir Bečirević , Ilja Doršner , Svjetlana Fajfer , Darius A. Faroughy , Florentin Jaffredo , Nejc Košnik , Olcyr Sumensari

The measurements of $R_K^{(*)}$ and $R_{D}^{(*)}$ by BaBar, Belle and the LHCb collaborations could be showing a hint of lepton flavor universality violation that can be accommodated by the presence of suitable leptoquarks at the TeV scale.…

High Energy Physics - Phenomenology · Physics 2018-12-20 Ezequiel Alvarez , Leandro Da Rold , Aurelio Juste , Manuel Szewc , Tamara Vazquez Schroeder

In this paper, we argue that an extension of the Standard Model with a single leptoquark and three right-handed neutrinos can explain the excess in the first-generation leptoquark search at the LHC. We also find that when the leptoquark has…

High Energy Physics - Phenomenology · Physics 2015-07-23 Jason L. Evans , Natsumi Nagata

Leptoquarks (LQ) with couplings to the third generation of Standard Model (SM) quarks have been proposed as possible explanations of the flavour anomalies indicating the violation of lepton flavour universality (LFV). The CMS collaboration…

High Energy Physics - Experiment · Physics 2018-09-13 Johannes Haller

The t-channel exchange of a first generation leptoquark could contribute to the cross-section for q q-bar to e+e-. The leptoquark is off-shell, so this process can be sensitive to leptoquarks beyond the mass reach of pair production…

High Energy Physics - Phenomenology · Physics 2015-06-22 Assia Bessaa , Sacha Davidson

$B$ physics plays important roles in searching for the new physics (NP) beyond the standard model (SM). Recently, some deviations between experimental data and SM predictions were reported, namely $R(D^{(*)})$, $P_5^\prime$ and…

High Energy Physics - Phenomenology · Physics 2018-08-10 Ying Li , Cai-Dian Lu

Searches for first generation scalar and vector leptoquarks, and for squarks in R-parity violating SUSY models with the direct decay of the squark into Standard Model particles, have been performed using e+e- collisions collected with the…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL collaboration , G. Abbiendi

We report on a search for the pair production of second generation scalar leptoquarks (LQ_2) in ppbar collisions at the center-of-mass energy sqrt(s) = 1.96 TeV, using data corresponding to an integrated luminosity of 294 +- 19 pb^-1…

High Energy Physics - Experiment · Physics 2008-11-26 D0 Collaboration , V. Abazov

Indirect signs of new physics beyond the Standard Model may be appearing in $B \to K^{(*)}\mu^+\mu^-$ decays. If confirmed, the title question will be of paramount importance in determining the strategy for future colliders. We answer it by…

High Energy Physics - Phenomenology · Physics 2018-05-14 Tevong You

We investigate the current LHC bounds on New Physics (NP) that contributes to $\bar B \to D^{(*)} l\bar\nu$ for $l = (e,\mu,\tau)$ by considering both leptoquark (LQ) models and an effective-field-theory (EFT) Hamiltonian. Experimental…

High Energy Physics - Phenomenology · Physics 2022-08-23 Syuhei Iguro , Michihisa Takeuchi , Ryoutaro Watanabe

We show that a modification of the model with a low energy scalar leptoquark state carrying hypercharge $Y=7/6$ allows to accommodate both $R_K<1$ and $R_{K^\ast}<1$, through loop effects, consistent with recent observations made at LHCb.…

High Energy Physics - Phenomenology · Physics 2018-06-01 Damir Bečirević , Olcyr Sumensari

Over the past years, experiments accumulated intriguing hints for new physics (NP) in flavor observables, namely in the anomalous magnetic moment of the muon ($a_\mu$), in $R(D^{(*)})={\rm Br}(B\to D^{(*)}\tau\nu)/{\rm Br}(B\to…

High Energy Physics - Phenomenology · Physics 2017-10-11 Andreas Crivellin , Dario Müller , Toshihiko Ota

Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B $\to$ D$^{(*)}\tau\nu$, hints of lepton universality violation in B $\to$ K$^{(*)}\ell\ell$ decays, and the anomalous magnetic…

High Energy Physics - Experiment · Physics 2019-03-14 CMS Collaboration

We use a combined analysis of the semileptonic and leptonic branching ratios of the D mesons to constrain scalar leptoquark interactions and charged higgs-like interactions. For the THDM type II, we found that a low mass 6.3GeV < m_{H^+} <…

High Energy Physics - Phenomenology · Physics 2014-04-03 J. Barranco , D. Delepine , V. Gonzalez Macias , L. Lopez-Lozano

We report on D0 searches for leptoquarks (LQ) predicted in extended gauge theories and composite models to explain the symmetry between quarks and leptons. Data samples obtained with the D0 detector from proton-antiproton collisions at a…

High Energy Physics - Experiment · Physics 2009-10-07 Sergey A. Uzunyan

Evidence for electron-muon universality violation that has been revealed in $b\to s \ell\ell$ transitions in the observables $R_{K,K^*}$ by the LHCb Collaboration can be explained with spin-1 leptoquarks in $SU(2)_L$ singlet $V_1$ or…

High Energy Physics - Phenomenology · Physics 2021-06-30 Gudrun Hiller , Dennis Loose , Ivan Nišandžić

We revisit a class of Z' explanations of the anomalies found by the LHCb collaboration in $B$ decays, and show that the scenario is tightly constrained by a combination of constraints: (i) LHC searches for di-muon resonances, (ii)…

High Energy Physics - Phenomenology · Physics 2017-05-02 Ben Allanach , Farinaldo S. Queiroz , Alessandro Strumia , Sichun Sun