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arXiv · 1710.06408

Computation of parton distributions from the quasi-PDF approach at the physical point

Constantia Alexandrou·Simone Bacchio·Krzysztof Cichy·Martha Constantinou·Kyriakos Hadjiyiannakou·Karl Jansen·Giannis Koutsou·Aurora Scapellato·Fernanda Steffens
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Abstract

We show the first results for parton distribution functions within the proton at the physical pion mass, employing the method of quasi-distributions. In particular, we present the matrix elements for the iso-vector combination of the unpolarized, helicity and transversity quasi-distributions, obtained with $N_f=2$ twisted mass clover-improved fermions and a proton boosted with momentum $|\vec{p}|=0.83\mbox{ GeV}$. The momentum smearing technique has been applied to improve the overlap with the proton boosted state. Moreover, we present the renormalized helicity matrix elements in the RI$'$ scheme, following the non-perturbative renormalization prescription recently developed by our group.

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Constantia Alexandrou, Simone Bacchio, Krzysztof Cichy, Martha Constantinou, Kyriakos Hadjiyiannakou, Karl Jansen, Giannis Koutsou, Aurora Scapellato, Fernanda Steffens. 2017-10-17. Computation of parton distributions from the quasi-PDF approach at the physical point. https://doi.org/10.1051/epjconf/201817514008

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