2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48664We have calculated the cross section of $ψ'$ photoproduction at small-$p_{T}$ regions in polarized $γp$ collisions for testing the color-octet model, which is based on NRQCD factorization formalism. We show that the measurement of the two-spin asymmetry of this process might be effective to constrain the value of NRQCD matrix elements.4 pages including 2 ps-figures, use sprocl.sty and psfig.tex, Latex. Talk given at the 1998 YITP Workshop on "QCD and Hadron Physics", (Kyoto, Japan, Oct. 14-16, 1998)High Energy Physics - Phenomenologytext