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Partonic angular momentum in the nucleons chiral periphery

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 نشر من قبل Carlos Granados
 تاريخ النشر 2019
  مجال البحث
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We study the nucleons partonic angular momentum (AM) content at peripheral transverse distances $b = mathcal{O}(M_pi^{-1})$, where the structure is governed by chiral dynamics. We compute the nucleon form factors of the energy-momentum tensor in chiral effective field theory (ChEFT) and construct the transverse densities of AM at fixed light-front time. In the periphery the spin density is suppressed, and the AM is predominantly orbital. In the first-quantized representation of ChEFT in light-front form, the field-theoretical AM density coincides with the quantum-mechanical orbital AM density of the soft pions in the nucleons periphery.

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