Related papers: Spin observables in antiproton-proton to AntiLambd…
General expressions, including the lepton mass, for the spin averaged differential cross section for the annihilation reaction lepton antilepton to proton antiproton are given, as well as general formulae for the single and double spin…
We present the complete eigenvalue spectrum of the partially transposed density matrix for a pure bipartite quantum state acting on a generic $2 \otimes n$ Hilbert space. The spectrum contains four non-zero eigenvalues, as, \begin{eqnarray}…
The static and dynamic susceptibilities for a general class of mean field random orthogonal spherical spin glass models are studied. We show how the static and dynamical properties of the linear and nonlinear susceptibilities depend on the…
Bethe-Salpeter equation is applied to $p$-$p$ elastic scattering. The observables of spin are calculated in the framework of the M matrix using the two-body interaction potential. The parameter of the pseudovector coupling constant is…
The analysis of some effects caused by the spin--dependent pomeron couplings is presented. It is shown that the structure of pomeron--proton and quark--pomeron couplings can be tested in future polarized experiments on elastic $pp$…
We propose for the spin density matrix two parametrizations which automatically fulfil the non-negativity conditions, without setting any bound on the parameters. The first one relies on a theorem, that we prove, and it is rather simple and…
New possibilities arising from the availability at GSI of antiproton beams, possibly polarised, are discussed. The investigation of the nucleon structure can be boosted by accessing in Drell-Yan processes experimental asymmetries related to…
The influence of Coulomb interaction on the phenomenon of "optical" spin rotation of negatively charged particles (antiprotons, etc.) moving in matter with polarized nuclei is considered. It is shown that because the density of the…
We analyze two types of spin observables in the reaction $\pi \vec D\to\vec\Sigma\Theta^+$ near the threshold. One concerns the spin-transfer coefficients $K_x^x$ and $K_z^z$. The second one is the deuteron spin anisotropy. These…
It is shown that the longitudinal double spin asymmetry $A_{ll}$ in polarized diffractive $Q \bar Q$ production depends strongly on the spin structure of the quark-pomeron vertex. Relevant experiments will be possible at HERA with a…
We investigate the constraints on the scalar, vector and spin-3/2 dark matter interaction with the standard model particles, from the observations of dark matter relic density, the direct detection experiments of CDMS and XENON, and the…
Positivity constraints, derived initially assuming parity conservation, for the inclusive reaction of the type $A({spin 1/2})+B({spin 1/2})\to C+X$, where the spins of both initial spin-1/2 particles can be in any possible directions and no…
In this work we study the constraints on the dark matter interaction with the standard model particles, from the observations of dark matter relic density, the direct detection experiments of CDMS and XENON, and the indirect detection of…
Spin observables in the photoproduction of the $\Theta^+$ are explored for the purpose of determining the parity of the $\Theta^+$. Based on reflection symmetry in the scattering plane, we show that certain spin observables in the…
In this work we study the pseudorapidity spectra o charged particles produced in proton+proton and proton+antiproton interactions in a wide energy range using the non-extensive Tsallis approach. We evaluate the inelasticity coefficients of…
A measurement of the Lamb shift in muonic hydrogen yields a charge radius of the proton that is smaller than the CODATA value by about 5 standard deviations. We explore the possibility that new scalar, pseudoscalar, vector, and tensor…
We discuss the apparent conflict between reflection positivity and positivity of the topological susceptibility in two-dimensional nonlinear sigma models and in four-dimensional gauge theories. We pay special attention to the fact that this…
The Coulomb interaction between electrons of opposite spin orientations in a metal or in a doped semiconductor results in a negative off-diagonal component of the electrical resistivity matrix -- the so-called "spin-drag resistivity". It is…
The PAX project at GSI Darmstadt plans to polarize an antiproton beam by repeated interaction with a hydrogen target in a storage ring. Many of the beam particles are required to remain within the ring after interaction with the target, so…
Spin observables of a binary reaction $1+2\to 3+4$ are discussed at the threshold in general form using P-parity and angular momentum conservation. General formulae for polarization transfer, spin-spin correlation parameters in the initial…