Production Asymmetry Measurement of High Xt Hadrons in pp Collisions at 40 GeV

TL;DR

This study measures single-spin asymmetries of various hadrons produced in polarized proton collisions at 40 GeV, revealing linear dependence on Xt and sign changes, with results compared to models and other experiments.

Contribution

It provides new measurements of hadron asymmetries at 40 GeV, showing their dependence on Xt and comparing findings with theoretical predictions and prior data.

Findings

Asymmetries for pi+-, K+-, and antiprotons depend linearly on Xt.

Sign change in asymmetries occurs near Xt = 0.37.

Protons exhibit negative asymmetry independent of Xt.

Abstract

Single-spin asymmetries for hadrons have been measured in collisions of transversely-polarized 40 GeV/c proton beam with an unpolarized liquid hydrogen target. The asymmetries were measured for pi+-, K+-, protons and antiprotons, produced in the central region (0.02 < Xf < 0.10 and 0.7 < Pt < 3.4 GeV/c). Asymmetries for pi+-, K+- and antiprotons show within measurement errors the linear dependence on Xt and change a sign near 0.37. For protons negative asymmetry, independent of Xt has been found. The results are compared with those of other experiments and SU(6) model predictions.