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Polarization in Hadronic ΛHyperon Production and Chiral-Odd Twist-3 Distribution

Y. Kanazawa·Yuji Koike
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Abstract

Polarization of the Λhyperon produced with a large transverse momentum in the unpolarized nucleon-nucleon collision is analyzed in the framework of QCD factorization. We focus on the mechanism in which the soft-gluon component of the chiral-odd spin-independent twist-3 quark distribution E_F(x,x) becomes a source of the polarized quark fragmenting into the polarized Λ. Our simple model estimate for this contribution indicates that it gives rise to a significant Λpolarization at large x_F. This is in parallel with the observation that the soft gluon pole mechanism gives rise to a large single transverse spin asymmetry in the pion production at x_F\to 1.

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Y. Kanazawa, Yuji Koike. 2001-05-24. Polarization in Hadronic ΛHyperon Production and Chiral-Odd Twist-3 Distribution. https://doi.org/10.1103/physrevd.64.034019

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