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arXiv · 2405.16269

Pion gravitational form factors in the QCD instanton vacuum II

Wei-Yang Liu·Edward Shuryak·Ismail Zahed
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Abstract

We revisit the hard QCD contributions to the pion gravitational form factors (GFFs), in terms of the twist-2,3 pion distribution amplitudes (DA), including novel semi-hard contributions from the instantons. The pion DAs are evaluated in the QCD instanton vacuum, and then properly evolved to higher resolution. The results are compared to our recent results from the QCD instanton vacuum, as well as Bethe-Salpeter calculations and recent lattice data. The interpolated hard and soft contributions to the pion D-form-factor, are used to derive the (gravitational) pressure and shear within the pion, with a clear delineation of their range.

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Wei-Yang Liu, Edward Shuryak, Ismail Zahed. 2024-05-25. Pion gravitational form factors in the QCD instanton vacuum II. https://doi.org/10.1103/physrevd.110.054022

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