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arXiv · 2209.02355

Quark-model relations among TMDs in the parton model

F. Aslan·S. Bastami·A. Mahabir·A. Tandogan·P. Schweitzer
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Abstract

The covariant parton model (CPM) is a consequent application of the parton model concept to the nucleon structure. In this model, there is a choice to put quarks either in a pure-spin state or in a mixed-spin state. We show that the mixed-spin version of the CPM does not support the quark-model relations among transverse momentum dependent parton distributions (TMDs) which were shown to hold in a large class of quark models. One can enforce the quark-model relations to be valid in the CPM by imposing a condition which is equivalent to putting the quarks in a pure-spin state. This gives a complementary perspective on the connection of the pure- and mixed-spin state CPM versions, and provides a fresh view on the question whether the quark-model relations could be realized in QCD as "approximate relations" with some useful numerical accuracy.

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F. Aslan, S. Bastami, A. Mahabir, A. Tandogan, P. Schweitzer. 2022-09-06. Quark-model relations among TMDs in the parton model. https://doi.org/10.1103/physrevd.106.096010

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