Related papers: Transverse Spin Effects In Diffractive Hadron Lept…
We calculate the transverse double-spin asymmetry for the production of dimuons in pp collisions as function of the dimuon rapidity and mass to next-to-leading accuracy in the strong coupling. Predictions for BNL-RHIC and HERA-N are made by…
We calculate the single-spin and double-spin asymmetry differential cross sections for the polarized hadron scattering $PP \to l^+ l^- + jet$ up to $O(\alpha_s)$ by the helicity amplitude method. Numerical results of the differential cross…
We present a consistent calculation of the structure functions within a light-front constituent quark model of the nucleon. Relativistic effects and the relevance of the covariance constraints are analyzed for polarized parton…
Anomalous contributions to the electric and magnetic dipole moments of the $\tau$ lepton from new physics scenarios have brought renewed interest in the development of new charge-parity violating signatures in $\tau$-pair production at…
The longitudinal double spin asymmetry A_LL in the reaction pp --> pi X has been measured at RHIC with extremely interesting consequences. If the gluon polarization in a proton were as big as needed to resolve the famous "spin crisis" then…
We discuss the impact on the study of gluon transverse momentum dependent distributions (TMDs) of the associated production of a lepton pair and a $\Upsilon$ (or a $J/\psi$) in unpolarised proton-proton collisions, $pp\to {\cal Q} \, \ell…
Measurements of double helicity asymmetries for inclusive hadron production in polarized proton-proton collisions are sensitive to spin-dependent parton distribution functions, in particular to the gluon distribution, Delta g. This study…
The production of $W^{\pm}$ and $Z^0$ bosons in collisions of longitudinally polarized protons allows to access various combinations of the polarized quark distributions from the study of double and single spin asymmetries. We compute the…
Polarization asymmetries in photoproduction of high transverse momentum mesons are a flavor sensitive way to measure the polarized quark distributions. We calculate the expected asymmetries in several models, and find that the asymmetries…
We discuss the double-spin asymmetries in transversely polarized Drell-Yan process, calculating all-order gluon resummation corrections up to the next-to-leading logarithmic accuracy. This resummation is relevant when the…
A phenomenological description of single transverse spin asymmetries for the inclusive production of hadrons in proton-proton and lepton-proton processes is discussed within pQCD and a straightforward generalization of the factorization…
Using a generalized parton model approach including spin and intrinsic parton motion effects, and assuming the validity of factorization for large-pT jet production in hadronic collisions, we study the azimuthal distribution around the jet…
We study the longitudinal-transverse double spin asymmetry $A_{LT}$ for direct photon production in nucleon-nucleon scattering by using the collinear twist-3 approach. This asymmetry, which, for instance, could be measured at RHIC, contains…
We study the semi-inclusive production of real, high-$p_T$, isolated photons in unpolarized and polarized lepton-proton collisions, $\ell p\to \ell\gamma X$. In particular we analyze the transverse nucleon single-spin asymmetry within the…
We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction, where two hadrons are produced in opposite hemispheres along the z-axis in the center-of-mass…
To test the model of the polarized gluon distribution $\Delta G(x, Q^2)$ in the proton, we propose a new process, diffractive $\Lambda_c^+$ productions in polarized $pp$ reactions, which will be observed in the forthcoming RHIC and also the…
We discuss specific observables that can be measured in deep inelastic leptoproduction in the case of 1-particle inclusive measurements, namely azimuthal asymmetries. These asymmetries contain information on the intrinsic transverse…
We report the first measurement of the longitudinal double-spin asymmetry $A_{LL}$ for mid-rapidity di-jet production in polarized $pp$ collisions at a center-of-mass energy of $\sqrt{s} = 200$ GeV. The di-jet cross section was measured and…
The small $x$ behaviour of polarized parton distributions is related to non-leading reggeons in the framework of the high-energy effective action. Double-logarithmic contributions to the reggeon interaction beyond the ones included in the…
We discuss polarized parton distributions and their effects on spin asymmetries at RHIC. In particular, transversity distributions and transverse spin asymmetry are studied. First, we show the $Q^2$ evolution difference between a…