A toy model for generalised parton distributions
نویسنده
چکیده
We give the results of a simple model for the diagonal and off-diagonal valence quark distributions of a pion. We show that structure can be implemented in a gauge-invariant manner. This explicit model questions the validity of the momentum sum rule, and gives an explicit counter-example to the WandzuraWilczek ansatz for twist-3 GPD’s.
منابع مشابه
ar X iv : h ep - p h / 05 07 28 1 v 1 2 5 Ju l 2 00 5 A toy model for generalised parton distributions
We give the results of a simple model for the diagonal and off-diagonal valence quark distributions of a pion. We show that structure can be implemented in a gauge-invariant manner. This explicit model questions the validity of the momentum sum rule, and gives an explicit counter-example to the WandzuraWilczek ansatz for twist-3 GPD’s.
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تاریخ انتشار 2005