DOI 10.1007/s100520000355
A new scaling law for analyzing power
in hadron production
by transversely polarized baryons
V.V. Abramov
Experimental Physics Department,
Institute for High Energy Physics, P.O. Box 35,
Protvino, 142284 Moscow region, Russia
(e-mail: abramov_v@mx.ihep.su)
Received: 19 October 1999 / Revised version: 26 January 2000 /
Published online: 6 March 2000
- © Springer-Verlag 2000
Abstract
Experimental data on analyzing power for inclusive meson and
baryon production in collisions of transversely polarized protons and
antiprotons with protons and light nuclei have been analyzed. It is
found that the existing data can be described by a simple function of
collision energy (
), transverse momentum (
pT )
and a new scaling variable
xA =
E/EBEAM . At beam
energies above 40 GeV and
pT above 1.0 GeV/c the
analyzing power is described by a function of
xA and
pT only (
AN =F (pT
)G (xA )) for both polarized proton fragmentation
and central regions of proton-hadron collision. Comparison of data from
Fermilab and new IHEP data measured using 40 GeV/c polarized proton beam
was most decisive for the revelation of the above regularities. This
new scaling law allows one to predict the analyzing powers for kinematic
regions, not yet explored in experiments and constrains models of strong
interactions. The new scaling law allows one also to use some reactions
as polarimeters for experiments with a polarized beam.
Copyright Società Italiana di Fisica, Springer-Verlag 2000
