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Longitudinal Contribution to the Alignment Polarization of Quarks Produced in e+ e- Annihilation: An O(alpha_s) Effect

S. Groote·J. G. K"orner·M. M. Tung
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Abstract

We calculate the longitudinal contribution to the alignment polarization $\Pl$ of quarks produced in $e^+e^-$ annihilation. In the Standard Model, the longitudinal alignment polarization vanishes at the Born term level and thus receives its first non-zero contribution from the $O(\as)$ tree graph process. We provide analytical and numerical results for the longitudinal alignment polarization of massless and massive quarks, in particular for the recently discovered top quark.

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S. Groote, J. G. K"orner, M. M. Tung. 1995-07-04. Longitudinal Contribution to the Alignment Polarization of Quarks Produced in e+ e- Annihilation: An O(alpha_s) Effect. https://arxiv.org/abs/hep-ph/9507222

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