Related papers: Lambda and Lambda-bar polarization as a measuremen…
We check the $u$ and $d$ quark contributions to the spin content of the $\Lambda$ by means of the $q\to\Lambda$ fragmentation and find that the $u$ and $d$ quarks of the $\Lambda$ are likely positively polarized. The parton distributions in…
This article is an introduction to parton distribution functions and their generalizations which describe the quark and gluon structure of hadrons, and can be measured in various high-energy scattering processes. We provide the theoretical…
Transverse $\Lambda$ polarization observed over four decades ago contradicted expectations from early leading-order perturbative QCD calculations. Measurements of $\Lambda$ polarization from unpolarized $pp$ and $p$A collisions have been…
In this paper we present a comprehensive formalism for dilepton production from the collision of two polarized spin-$\tfrac{1}{2}$ hadrons by identifying the general angular distribution of the cross section in combination with a complete…
We study the production of polarized $\Lambda$-hyperons in electron-positron annihilation. We are particularly interested in the transverse-spin dependence of the cross section for unpolarized incident electron-positron pairs. At high…
In hydrodynamic approach to relativistic heavy ion collisions, hadrons with nonzero spin, produced out of the hydrodynamic medium, can acquire polarization via spin-vorticity thermodynamic coupling mechanism. The hydrodynamical quantity…
In the 1970s, an unexpected transverse $\Lambda$ polarization in unpolarized proton-Beryllium collisions was discovered, which initiated extensive studies on spin phenomena in high-energy physics. Over the past five decades, similar…
Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. $\Lambda_b$ ,…
The Lambda polarization in muon neutrino charged current interactions has been measured in the NOMAD experiment. We observe negative polarization along the W - boson direction which is enhanced in the target fragmentation region: Px (xF <…
We analyze experimental data for the production of Lambda baryons in e^+e^- annihilation in terms of scale dependent, QCD evolved, Lambda fragmentation functions. Apart from the vast majority of the data for which the polarization of an…
Based on the observation of sizeable target-transverse-spin asymmetries in single-hadron and hadron-pair production in Semi-Inclusive measurements of Deep Inelastic Scattering (SIDIS), the chiral-odd transversity quark distribution…
We study the fragmentation of a transversely polarized quark into a non collinear (k_T not= 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative…
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…
The observed polarisation of Lambda hyperons from the inclusive pA -> Lambda X reaction at high energies has previously been well described within the Lund string model through polarised ss quark pair production in the string breaking…
These notes provide an introduction to polarization effects in deep inelastic processes in QCD. We emphasize recent work on transverse asymmetries, subdominant effects, and the role of polarization in fragmentation and in purely hadronic…
We propose a new procedure for parton-to-hadron fragmentation in proton-proton collisions. The hadronization is considered in the parton-parton center-of-mass system and hadrons are assumed to be emitted in the direction of outgoing partons…
This is a review of progress in hadron structure physics from lattice QCD. Recent results on the structure of the nucleon and the pion in terms of (transition) form factors, moments of distribution amplitudes and (generalized) parton…
Parton distribution functions (DFs) have long been recognised as key measures of hadron structure. Today, theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction…
The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda…
Hadron spin physics is now one of the most active fields of physics. Especially in the last ten years, great progress has been made both theoretically and experimentally that has considerably improved our knowledge of the spin structure of…