Related papers: Quantum Interference Effects Among Helicities at L…
Determining the spin of new particles is critical in identifying the true theory among various extensions of the Standard Model at the next generation of colliders. Quantum interference between different helicity amplitudes was shown to be…
Many of the proposed solutions to the hierarchy and naturalness problems postulate new `partner' fields to the standard model particles. Determining the spins of these new particles will be critical in distinguishing among the various…
Spin observables may reveal much deeper properties of non perturbative hadronic physics than unpolarized quantities. We discuss the polarization of hadrons produced in $e^+e^-$ annihilation at LEP. We show how final state $q \bar q$…
We investigate the quantum interference shifts between energetically close states, where the state structure is observed by laser spectroscopy. We report a compact and analytical expression that models the quantum interference induced shift…
Recent results on hard diffraction at HERA and the Tevatron are presented. Charged particle multiplicities in diffraction and differences in multiplicity in quark and gluon jets measured at LEP are discussed. Spin effects in the…
Recent theories propose that quantum gravity effects may be observable at LEP energies via gravitons that couple to Standard Model particles and propagate into extra spatial dimensions. The associated production of a graviton and a photon…
Quantum interference between energetically close states is theoretically investigated, with the state structure being observed via laser spectroscopy. In this work, we focus on hyperfine states of selected hydrogenic muonic isotopes, and on…
We propose to observe the top spin correlation effect at Tevatron through the measurement of the correlated asymmetries of the charged lepton momenta using the dilepton decay events of top and anti-top quark pairs. The possibility of…
Recent experiments are reviewed that explore the spin states of a ring-shaped many-electron quantum dot. Coulomb-blockade spectroscopy is used to access the spin degree of freedom. The Zeeman effect observed for states with successive…
Interference effects are widely neglected in searches for new physics. This is the case in recent publications on searches for W'-bosons using leptonic final states. We examine the effects of interference on distributions frequently used to…
For a particle travelling through an interferometer, the trade-off between the available which-way information and the interference visibility provides a lucid manifestation of the quantum mechanical wave-particle duality. Here we analyze…
We derive a simple analytic expression for q \bar{q}, g g -> t \bar{t} -> b W^+ \bar{b} W^- -> b \bar{l} \nu_l \bar{b} l' \bar{\nu_{l'}} for on shell intermediate states with the interference effects due to the polarizations of the t and…
We study quantum coherence in top-antitop production at the LHC by comparing Standard Model predictions with CMS data across different kinematic regimes. Theory and experiment are statistically consistent in the near-threshold and boosted…
We investigate the effects of resonance-continuum interference on the diphoton spectrum in the presence of a new spin-0 or spin-2 state produced via gluons or quarks and decaying to pairs of photons. Interference effects can significantly…
We present a quantitative assessment of the impact a future electron-ion collider will have on determinations of helicity quark and gluon densities and their contributions to the proton spin. Our results are obtained by performing a series…
We quantitatively discuss the possibility of deriving model-independent constraints on the general four-fermion contact interaction couplings, from the currently available data on the two-fermion production processes $e^+e^-\to\mu^+\mu^-$,…
The analyses of recent LEP data provide us with a rich ground for pQCD and LPHD tests. A number of non-trivial effects predicted in the framework of MLLA are experimentally verified. Recent measurements also enrich our knowledge about the…
Using a simple analytic expression for $q \bar{q}, g g \rightarrow t \bar{t} \rightarrow b W^+ \bar{b} W^- \rightarrow b \bar{l} \nu_l \bar{b} l' \bar{\nu_{l'}}$ with the interference effects due to the polarizations of the $t$ and…
Data from HERA, LEP and the Tevatron, as well as from low energy experiments are used to constrain the scale of possible electron-quark contact interactions. Different models are considered, including the most general one, in which all new…
Despite their inextricable quantum mechanical nature, events at a high energy particle collider experiment typically have very few unambiguous quantum signatures, due the type of data and the manner in which they are collected. We present a…