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arXiv · 1012.2899

Quark splitting in non-trivial θ-vacuum

Hongxi Xing·Xin-Nian Wang·Feng Yuan
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Abstract

Quark splitting in non-trivial $θ$-vacuum with a given helicity is investigated in pQCD with a modified quark propagator. We found that the quark splitting functions were modified by the presence of a topologically non-trivial QCD background field, though there is no explicit helicity flip associated with the radiative processes. The interaction with the topological non-trivial field leads to the degeneracy of the quark splitting functions for left- and right-handed quarks. Such degeneracy can lead to imbalance of left- and right-handed quarks in quark jet showers. We also discuss phenomenological consequences of such imbalance if there exists non-trivial topological gluon field configuration in heavy-ion collisions.

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Hongxi Xing, Xin-Nian Wang, Feng Yuan. 2010-12-13. Quark splitting in non-trivial θ-vacuum. https://doi.org/10.1016/j.nuclphysa.2011.02.109

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