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Related papers: Exotic leptoquarks from superstring derived models

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We study the production of doubly charged excited leptons at the LHC. These exotic states are predicted in extended weak isospin composite models. A recent analysis of such exotic states was based on a pure gauge model with magnetic type…

High Energy Physics - Phenomenology · Physics 2014-08-13 R. Leonardi , O. Panella , L. Fanò

We perform a systematic study of models involving leptoquarks and diquarks with masses well below the grand unification scale and demonstrate that a large class of them is excluded due to rapid proton decay. After singling out the few…

High Energy Physics - Phenomenology · Physics 2018-01-09 Nima Assad , Bartosz Fornal , Benjamin Grinstein

Experimental hints for lepton flavor universality violation in beauty-quark decay both in neutral- and charged-current transitions require an extension of the Standard Model for which scalar leptoquarks (LQs) are the prime candidates.…

High Energy Physics - Phenomenology · Physics 2022-09-21 J. Julio , Shaikh Saad , Anil Thapa

Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide…

High Energy Physics - Phenomenology · Physics 2018-12-18 Bradley L. Rachlin , Thomas W. Kephart

In this talk I will present the work that we did in \cite{1}\cite{2}\cite{3}\cite{4}\cite{5} related to observed lepton universality violation by Babar, Belle and LHCb in R($D^{(*)}$) and $R_{K^{(*)}}$ as well as the reported deviation in…

High Energy Physics - Phenomenology · Physics 2019-09-04 Lobsang Dhargyal

In a model in which quarks and leptons are built up from two spin 1/2 preons as fundamental entities, a new class of fermionic bound states (hyperquarks) arises. It turns out that these hyperquarks are necessary to fulfill the 't Hooft…

High Energy Physics - Phenomenology · Physics 2015-06-15 Alfons J. Buchmann , Michael L. Schmid

Flavor physics may help us understand theories beyond the standard model. In the context of supersymmetry, if we can measure the masses and mixings of sleptons and squarks, we may learn something about supersymmetry and supersymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-20 Jonathan L. Feng , Sky T. French , Iftah Galon , Christopher G. Lester , Yosef Nir , Yael Shadmi , David Sanford , Felix Yu

An analysis is presented of events containing jets including at least one $b$-tagged jet, sizable missing transverse momentum, and at least two charged leptons including a pair of the same electric charge, with the scalar sum of the jet and…

High Energy Physics - Experiment · Physics 2016-11-22 Cecile Deterre

Quark-lepton compositeness is a well-known beyond the Standard Model (SM) scenario with heavy exotic particles like leptoquarks (LQs) and leptogluons (LGs) etc. These particles can couple to leptons and jets simultaneously. In this letter,…

High Energy Physics - Phenomenology · Physics 2018-09-13 Tanumoy Mandal , Subhadip Mitra , Satyajit Seth

We present a Z_6 orbifold compactification of the E_8xE_8 heterotic string which leads to the (supersymmetric) Standard Model gauge group and matter content. The quarks and leptons appear as three 16-plets of SO(10), whereas the Higgs…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wilfried Buchmuller , Koichi Hamaguchi , Oleg Lebedev , Michael Ratz

The long-standing anomaly in the anomalous magnetic moment of the muon indicates the presence of chirality violating new physics contributions. A possible solution involves scalar leptoquarks with left- and right-handed couplings to the top…

High Energy Physics - Phenomenology · Physics 2017-03-29 Estefania Coluccio Leskow , Andreas Crivellin , Giancarlo D'Ambrosio , Dario Müller

Observed neutrino oscillations imply that the global lepton flavor symmetry of the Standard Model must be broken. Therefore, searches for lepton flavor violation (LFV) are promising probes of new physics beyond the Standard Model.…

High Energy Physics - Phenomenology · Physics 2025-07-23 P. S. Bhupal Dev

The Standard Model (SM) is augmented with a $\mathrm{U}(1)_{B-3L_\mu} $ gauge symmetry spontaneously broken above the TeV scale when an SM-singlet scalar condenses. Scalar leptoquarks $S_{1(3)} = (\overline{\mathbf{3}},\, \mathbf{1}…

High Energy Physics - Phenomenology · Physics 2021-08-04 Admir Greljo , Peter Stangl , Anders Eller Thomsen

Supersymmetric theories generally have new flavor violation sources in the squark and slepton mass matrices. If significant lepton flavor violation exists, selectron and smuon should be nearly degenerate. This leads to the phenomenon of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hsin-Chia Cheng

In this Lecture we first review the basic properties that make flipped SU(5) a very economical and well motivated unified model, including some recent developments regarding the prediction for $\alpha_s$ and new implications for proton…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Lopez , D. Nanopoulos

I investigate the phenomenology of supersymmetric models with extra vector-like supermultiplets that couple to the Standard Model gauge fields and transform as the fundamental representation of a new confining non-Abelian gauge interaction.…

High Energy Physics - Phenomenology · Physics 2011-03-23 Stephen P. Martin

We study extensions of the standard model by one generation of vector-like leptons with non-standard hypercharges, which allow for a sizable modification of the h -> gamma gamma decay rate for new lepton masses in the 300 GeV - 1 TeV range.…

High Energy Physics - Phenomenology · Physics 2022-12-09 Wolfgang Altmannshofer , Martin Bauer , Marcela Carena

The production at the LHC of exotic excited leptons of charge $Q = +2e$ is considered. Such states are predicted in composite models with extended isospin multiplets ($I_{W}=1$ and $I_{W}=3/2$). The coupling among these doubly charged…

High Energy Physics - Phenomenology · Physics 2014-06-26 Simone Biondini , Orlando Panella , Giulia Pancheri , Yogendra Srivastava , Livio Fanò

Scores of exotic hadrons, particularly tetraquarks and pentaquarks in the heavy-quark sector, have been observed in the past 20 years, and more continue to be discovered to this day. Unlike mesons and baryons, such exotics are not mandated…

High Energy Physics - Phenomenology · Physics 2023-08-03 Richard F. Lebed

Leptoquarks (LQs) have been extensively studied in the context of $B$ anomalies. When $U(1)_{L_\mu-L_\tau}$ is introduced to a scalar LQ model with the LQ $S_1$ charged under the new symmetry, $S_1$ primarily couples to the third-generation…

High Energy Physics - Phenomenology · Physics 2023-10-05 Chuan-Hung Chen , Cheng-Wei Chiang