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تسجيل مستخدم جديدSmall size instanton contributions to the quark quasi-PDF and matching kernel
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We investigate the non-perturbative contribution of instantons to current matching kernels used in the context of the large momentum effective theory (LaMET). We derive explicitly these contributions using first principle semi-classical calculus for the unpolarized and polarized quark parton distributions and the matching kernel, and show that they are part of a trans-series expansion. These contributions are substantial at current lattice matching momenta.
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