Double Spin Asymmetries in P - wave Charmonium
نویسنده
چکیده
We discuss the double spin asymmetries in P-wave charmonium hadroproduction with non-zero transverse momenta at fixed target energies, √ s ≃ 40 GeV, within the framework of the factorization approach. The size of the asymmetries and the projected statistical errors in a future option of HERA with longitudinally polarized protons scattering off a polarized target (HERA-N) are calculated. Measurements of the χ c1 and χ c2 decays into dilepton plus photon should allow to distinguish between different parametrizations for the polarized gluon distribution in the proton. At higher energies (√ s = 200 GeV) the situation appears less favourable with the presently envisaged integrated luminosities of the polarized RHIC collider.
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تاریخ انتشار 1998