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Related papers: Contact Interactions, Large Extra Dimensions and L…

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We study the effects of virtual leptoquarks on charged current and neutral current processes at the $ep$ collider HERA. We present the areas of parameter space that can be excluded at HERA by searching for deviations from Standard Model…

High Energy Physics - Phenomenology · Physics 2009-10-22 M. A. Doncheski , J. L. Hewett

The excess of high-$Q^2$ events found by H1 and ZEUS at HERA in $e^+p$ deep-inelastic scattering above the Standard Model prediction motivates us to calculate the NLO QCD corrections to the HERA scalar leptoquark (or squark) production…

High Energy Physics - Phenomenology · Physics 2016-09-06 Z. Kunszt , W. J. Stirling

We study the impact of contact interactions involving two leptons (electrons or muons) and two $b$-quarks ($b \bar{b} \ell^+ \ell^-$) on the high-mass di-lepton region at the LHC. We consider different selections of $b$-tagged jet…

High Energy Physics - Experiment · Physics 2020-06-18 Yoav Afik , Shaouly Bar-Shalom , Jonathan Cohen , Yoram Rozen

We discuss the general framework for the construction of new models containing a single, fermion number zero scalar leptoquark of mass $\simeq 200-220$ GeV which can both satisfy the D0/CDF search constraints as well as low energy data, and…

High Energy Physics - Phenomenology · Physics 2009-10-30 JoAnne L. Hewett , Thomas G. Rizzo

We explore the viability of detecting a leptophilic scalar dark matter at the ILC in a simplified model approach. We present the constraints on the couplings of scalar dark matter with the standard model fermions ensuing from the relic…

High Energy Physics - Phenomenology · Physics 2025-03-20 Bharti Rawat

Unparticles ($\U$) interact weakly with particles. The direct signature of unparticles will be in the form of missing energy. We study constraints on unparticle interactions using totally invisible decay modes of $Z$, vector quarkonia $V$…

High Energy Physics - Phenomenology · Physics 2009-01-06 Shao-Long Chen , Xiao-Gang He , Ho-Chin Tsai

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

The four fermion contact interactions, required to explain the anomalous HERA result, could come from the exchange of new heavy (probably composite) resonances. Depending on their charges and quantum numbers, one gets different scenarios…

High Energy Physics - Phenomenology · Physics 2009-10-30 F. Caravaglios

Neutrino-nucleus coherent scattering measurements by the COHERENT collaboration provide us with a unique capability to test various beyond the standard model scenarios. In this work, we constrain scalar leptoquarks (LQs) using the COHERENT…

High Energy Physics - Phenomenology · Physics 2023-03-29 Roberta Calabrese , Jacob Gunn , Gennaro Miele , Stefano Morisi , Samiran Roy , Pietro Santorelli

We investigate the sensitivity of the 21cm power spectrum from cosmic dawn and the epoch of reionization to models of free-streaming dark radiation (parameterized through $N_{\rm eff}$) and interacting dark radiation-dark matter models…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Hugo Plombat , Théo Simon , Jordan Flitter , Vivian Poulin

In this paper searches are presented for the pair production of first and second generation scalar leptoquarks and limits are given on the quark-lepton compositeness scale from proton-antiproton collision data at a center-of-mass energy…

High Energy Physics - Experiment · Physics 2010-04-22 Maxim Titov

While the hunt for new states beyond the standard model (SM) goes on for various well motivated theories, the leptoquarks are among the most appealing scenarios at recent times due to a series of tensions observed in $B$-meson decays. We…

High Energy Physics - Phenomenology · Physics 2022-10-18 Priyotosh Bandyopadhyay , Anirban Karan , Rusa Mandal , Snehashis Parashar

Searches for contact interactions, leptoquark bosons and excited fermions carried out at the HERA ep collider are presented here. The searches are based on ~ 40 pb^-1 of e+ p data per experiment collected at a centre of mass energy ~ 300…

High Energy Physics - Experiment · Physics 2007-05-23 E. Perez

Several discrepancies in the decay of B-meson decay have drawn a lot of interest in the leptoquarks (LQ), making them an exciting discovery. The current research aims to discover the pair-production of leptoquarks that links strongly to the…

High Energy Physics - Phenomenology · Physics 2025-05-02 Ijaz Ahmed , Usman Ahmad , Jamil Muhammad , Saba Shafaq

The top-quark Yukawa coupling is extracted from the distribution of the top-quark pair ($t \overline{t}$) invariant mass in proton-proton collisions using 140 ${fb}^{-1}$ of data at $\sqrt{s} = 13$ TeV collected in 2015-2018 by the ATLAS…

High Energy Physics - Experiment · Physics 2026-02-04 ATLAS Collaboration

I discuss the production of leptoquarks in $p\bar{p}$ collisions at the Fermilab Tevatron. Evaluated on the basis of a recent next-to-leading order calculation, the combined D0 and CDF leptoquark searches lead to a parameter-free lower mass…

High Energy Physics - Phenomenology · Physics 2008-02-03 Michael Krämer

The measurements of hadron and lepton-pair production cross sections and leptonic forward-backward asymmetries performed with the L3 detector at centre-of-mass energies between 130 GeV and 189 GeV are used to search for new physics…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

We analyze the sensitivity of next-generation tonne-scale neutrinoless double $\beta$-decay ($0\nu\beta\beta$) experiments and searches for same-sign di-electrons plus jets at the Large Hadron Collider to TeV scale lepton number violating…

High Energy Physics - Phenomenology · Physics 2016-05-11 Tao Peng , Michael J. Ramsey-Musolf , Peter Winslow

We study the potential of lepton collisions with about $10\text{ TeV}$ center of mass energy to probe Electroweak, Higgs and Top short-distance physics at the $100\text{ TeV}$ scale, pointing out the interplay with the long-distance…

High Energy Physics - Phenomenology · Physics 2022-06-15 Siyu Chen , Alfredo Glioti , Riccardo Rattazzi , Lorenzo Ricci , Andrea Wulzer

The prospects for producing leptoquarks (LQs) in ultrahigh-energy (UHE) neutrino nucleon collisions are re-examined in the light of recent interpretations of HERA data in terms of leptoquark production. We update predictions for…

High Energy Physics - Phenomenology · Physics 2016-09-06 M. A. Doncheski , R. W. Robinett