Related papers: Constraints on spin observables in pbar p --> Lamb…
It is recalled that spin-observables in the strangeness-exchange reaction $\bar{p}{p} \to \bar{\Lambda}{\Lambda}$ are not independent but are related to each other by simple algebraic relations. This provides constraints on the existing…
The positivity conditions of the spin density matrix constrain the spin observables of the reaction antiproton-proton to AntiLambda-Lambda, leading to model-independent, non-trivial inequalities. The formalism is briefly presented and…
We comment on the proposed measurement of the spin-depolarisation parameter $D_{nn}$ in the strangeness-exchange reaction $\bar{\rm p}{\rm p} \rightarrow \overline{\Lambda}{\Lambda}$. It is shown that the existing data on the correlation…
Spin transfer observables for the strangeness-production reaction Antiproton-Proton -> Antilambda-Lambda have been measured by the PS185 collaboration using a transversely-polarized frozen-spin target with an antiproton beam momentum of…
We point out that the measurement of target spin depolarization $D_{nn}$ in the $\bar{p}p\to\bar{\Lambda}\Lambda$ reaction may test dynamical mechanisms invoked to explain the proton spin puzzle revealed by polarized deep--inelastic…
The T matrix of the LambdaN-> NN reaction, which is a strangeness changing weak process, is derived. The explicit formulas of the spin observables are given for s-wave p-Lambda final states which kinematically corresponds to inverse…
Model-independent identities and inequalities relating the various spin observables of a reaction are reviewed in a unified formalism, together with their implications for dynamical models, their physical interpretation, and the quantum…
The Lambda polarization, the analyzing power, and the Lambda spin transfer coefficient of the reaction pp -> p K+ Lambda were measured at beam momenta of 2.70 GeV/c and 2.95 GeV/c, corresponding to excess energies of 122 MeV and 204 MeV.…
We discuss model-independent constraints on spin observables in exclusive and inclusive reactions, with special attention to the case of photoproduction.
Exclusive hadronic reactions with a massive lepton pair (l^+l^-) in the final state will be measured with PANDA at GSI-FAIR and with Compass at CERN, both in p+p-bar -> l^+l^-+pi and pi+N -> N'+l^+l^-. Similarly, electroproduction of a…
The formalism describing the scattering of two spin-1/2 objects is reviewed for the case of antilambda-lambda production from antiproton-proton annihilation. It is shown that an experiment utilizing a transverse target polarization can, in…
We study the production of longitudinally polarized Lambda-baryons in single-spin pp collisions at RHIC and HERA-N as a means of determining the spin-dependent Lambda fragmentation functions. It is shown that a measurement of the rapidity…
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…
Different phenomenological approaches for Lambda and Lambda-bar polarization in polarized semi-inclusive deep inelastic scattering and electron-positron annihilation at Z^0 pole are considered. Current and future experiments will soon…
The spin polarization of $\Lambda$ hyperons produced in inclusive reactions with unpolarized protons on unpolarized targets has been studied for almost 40 years. The NA61\SHINE experiment at the CERN SPS has a great potential to study…
We consider polarized Lambda hyperon production in proton-proton scattering, p p -> (\Lambda^\uparrow jet) jet X, in the kinematical region of the LHC experiments, in particular the ALICE experiment. We present a new Lambda polarization…
A formalism for spin observables of the reaction $pd\to ~^3He\eta$ is derived in a model independent way. The general case with a full set of six independent spin amplitudes is studied. Furthermore, approximations by five and four spin…
Using the symmetry properties of the strong interaction, such as the Pauli principle, the P-invariance, the conservation of the total angular momentum and isotopic invariance, we establish the spin structure of the threshold matrix elements…
We investigate the polarization parameters in low-energy antiproton-proton elastic ($\bar{p}p\rightarrow\bar{p}p$) and charge-exchange ($\bar{p}p\rightarrow\bar{n}n$) scattering. The predictions for unmeasured observables are based on our…
Polarization of $\Lambda$ hyperons has been observed in various collision systems over a wide range of collision energies over the last 50 years since its discovery in Fermilab in the 70's. The existing experimental and theoretical…