2023 Impact factor 4.2
Particles and Fields


Eur. Phys. J. C 20, 677-682 (2001)
DOI: 10.1007/s100520100686

Single spin asymmetries in $p\uparrow p \rightarrow \pi X$ and $\bar{p} \uparrow p \rightarrow \pi X$

G. Domínguez Zacarias, G. Herrera and I. León-Monzón

Centro de Investigación y de Estudios Avanzados, Apdo. Postal 14 740, México 07000, Mexico

galileo.dominguez@fis.cinvestav.mx
gherrera@fis.cinvestav.mx
ildefonso.leon@fis.cinvestav.mx

(Received: 15 February 2001 / Revised version: 24 April 2001 / Published online: 29 June 2001 -© Springer-Verlag / Società Italiana di Fisica 2001)

Abstract
We study the inclusive production of charged and neutral pions in the reactions $p\uparrow p \rightarrow \pi X$ and $\bar{p} \uparrow p \rightarrow \pi X$ in the framework of single spin asymmetries. We propose a two components model where production of pions occurs both by recombination of the constituents present in the initial state and by fragmentation of quarks in the final state. Taking the Thomas precession mechanism in the recombination component into account, we obtain a good description of the experimentally observed single spin asymmetries. We show that the observed single spin asymmetries are consistent with the measured spin alignment in the polarized proton as measured by HERMES and SMC.



© Società Italiana di Fisica, Springer-Verlag 2001