Nucleon transverse quark spin densities

Constantia Alexandrou; Simone Bacchio; Martha Constantinou; Petros Dimopoulos; Jacob Finkenrath; Roberto Frezzotti; Kyriakos Hadjiyiannakou; Karl Jansen; Bartosz Kostrzewa; Giannis Koutsou; Gregoris Spanoudes; Carsten Urbach

arXiv · 2210.05743

Nucleon transverse quark spin densities

Constantia Alexandrou·Simone Bacchio·Martha Constantinou·Petros Dimopoulos·Jacob Finkenrath·Roberto Frezzotti·Kyriakos Hadjiyiannakou·Karl Jansen·Bartosz Kostrzewa·Giannis Koutsou·Gregoris Spanoudes·Carsten Urbach

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Abstract

We present a calculation of the Mellin moments of the nucleon transverse quark spin densities extracted from the unpolarized and transversity generalized form factors. We use three $N_F=2+1+1$ ensembles of twisted mass fermions with quark masses tuned to their physical values and lattice spacings $a\sim 0.08$~fm, $a\sim 0.07$~fm and $a\sim 0.06$~fm and extrapolate the form factors to the continuum limit. Besides isovector densities we also include results for the tensor charge for each quark flavor using the ensemble with $a\sim 0.08$~fm for which we include the disconnected contributions.

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Constantia Alexandrou, Simone Bacchio, Martha Constantinou, Petros Dimopoulos, Jacob Finkenrath, Roberto Frezzotti, Kyriakos Hadjiyiannakou, Karl Jansen, Bartosz Kostrzewa, Giannis Koutsou, Gregoris Spanoudes, Carsten Urbach. 2022-10-11. Nucleon transverse quark spin densities. https://arxiv.org/abs/2210.05743

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