Single spin asymmetries and invariant cross-sections of the high transverse momentum inclusive pi0 production in 200-GeV/c p p and anti-p p interactions

The FNAL E704 collaboration Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Phys.Rev.D 53 (1996) 4747-4755, 1996.
Inspire Record 382392 DOI 10.17182/hepdata.40544

The π0 inclusive and semi-inclusive, single-spin asymmetries have been measured using transversely polarized, 200-GeV/c proton and antiproton beams colliding with an unpolarized hydrogen target. The measured asymmetries are consistent with zero within the experimental uncertainties for the kinematic region -0.15<xF<+0.15 and 1<pT<4.5 GeV/c. Improvements in the data analysis showed that our earlier large asymmetries at pT≳3 GeV/c were not correct. These data indicate that PQCD expectations seem confirmed and the higher-twist contribution to the single-spin asymmetry in π0 production at xF=0 is not large. Additional evidence for such a conclusion comes from the measurement of a semi-inclusive π0 asymmetry, where associated charged particles are detected opposite to the π0 azimuthal direction. This experiment also provides high-statistics data on the inclusive π0 cross sections for pp and p¯p collisions at √s≊19.4 GeV. © 1996 The American Physical Society.

3 data tables

No description provided.

Pure inclusive reaction.

Semi-inclusive reaction where at least on associated charged particle is produced at (180+-30) degrees relative to the pi0.