Related papers: Constraints on Electron-quark Contact Interactions
The Large Hadron Collider at CERN will provide Pb-Pb collisions at energies up to $\sqrt{s_{NN}}$ = 5.5 TeV. We speculate on global observables, i.e. the charged particle density at mid-rapidity, chemical freeze-out conditions and…
I present recent results on top quark production and properties in proton anti-proton collisions at a center of mass energy of 1.96 TeV. The measurements were performed by the CDF and D0 collaborations using approximately 3 fb-1 of data…
Spin correlations of top quarks produced in hadron collisions have not been observed experimentally with large significance. In this Letter, we propose a new variable that may enable demonstration of the existence of spin correlations with…
We present the recent results of top-quark physics using up to 6 fb$^{-1}$ of $p \bar p$ collisions at a center of mass energy of $\sqrt s$ = 1.96 TeV analyzed by the CDF collaboration. Thanks to this large data sample, precision top quark…
This work establishes 95% confidence level limits to models incorporating additional fermions sensitive to the strong interaction. Precision measurements of Transverse Energy-Energy Correlations at the ATLAS experiment are used, exploiting…
Recent results on charm fragmentation and hadron spectroscopy in $e^+/e^- p$ collisions at HERA with the ZEUS and H1 detectors are presented. The measured fragmentation ratios and fragmentation fractions are in agreement with those measured…
The search for new interactions of neutrinos beyond those of the Standard Model may help to elucidate the mechanism responsible for neutrino masses. Here we combine existing accelerator neutrino data with restrictions coming from a recent…
Multi-hadron production in inelastic neutrino-nucleon interactions is investigated within the framework of the quark-gluon string model. The contributions of the planar (one-Reggeon exchange) and cylindrical (one-Pomeron exchange) graphs to…
The discovery potential of the HERA collider, with and without polarized beams, for electron-quark contact interactions in neutral current scattering is reviewed. The measurement of spin asymmetries in the polarized case could give crucial…
This experimental review gives an overview of top-quark measurements performed by the two general purpose-detectors ATLAS and CMS during the first few years of running of the Large Hadron Collider. In the years 2010 - 2012 each experiment…
A new laboratory bound on the axial-vector mediated interaction between electron spins at micrometer scale is established with single nitrogen-vacancy (NV) centers in diamond. A single crystal of $p$-terphenyl doped pentacene-$d_{14}$ under…
A search is conducted for new resonant and non-resonant high-mass phenomena in dielectron and dimuon final states. The search uses 36.1 fb$^{-1}$ of proton-proton collision data, collected at $\sqrt{s}$ = 13 TeV by the ATLAS experiment at…
Heavy excited electrons and neutrinos have been sought by the H1 and ZEUS experiments at HERA. For the e* (nu*) searches, 120 pb^-1 (16 pb^-1) of ep collision data have been analysed. No evidence for any excited lepton has been found, and…
The standard model weak interactions can be described by four-fermion V-A operators at low energies. New physics at the TeV scale can, however, generate the other Lorentz structures. In this talk, we review the constraints on such…
Recent results on spectroscopy with special focus on searches for pentaquarks are presented from the H1 and ZEUS collaborations. Cross sections of observed states and upper limits on the production cross section of unobserved states are…
We present a detailed analysis on nonstandard neutrino interactions (NSI) with electrons including all muon and electron (anti)-neutrino data from existing accelerators and reactors, in conjunction with the ``neutrino counting'' data (e- e+…
Heavy quark production has been very well studied over the last years both theoretically and experimentally. Theory has been used to study heavy quark production in $e p$ collisions at HERA, in $pp$ collisions at Tevatron and at RHIC, in…
A search for first-generation leptoquarks was performed in electron-proton and positron-proton collisions recorded with the ZEUS detector at HERA in 2003-2007 using an integrated luminosity of 366 pb^-1. Final states with an electron and…
The electric dipole moments (EDMs) of nucleons are sensitive probes of additional $\cal CP$ violation sources beyond the standard model to account for the baryon number asymmetry of the universe. As a fundamental quantity of the nucleon…
At hadron colliders, top quarks are dominantly produced in pairs ($t\bar{t}$), a production mechanism that was discovered more than twenty years ago at the Tevatron in Fermilab. Although the \ttbar process has already entered the domain of…