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Nuclear Quark and Gluon Distributions in Coordinate Space

M. Vänttinen·G. Piller·L. Mankiewicz·W. Weise·K. J. Eskola
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Abstract

In coordinate space, quark and gluon distributions of the nucleon are defined as correlation functions involving two field operators separated by a light-cone distance $y^+ = 2l$. We study the nuclear modifications of these distributions. The largest effect is a strong depletion of parton distributions (shadowing) at large longitudinal distances, which starts for all parton species at $l=2$ fm, i.e. at the average nucleon-nucleon separation in nuclei. On the other hand, the nuclear radius does not play a significant role. At $l \lsim 1$ fm, nuclear modifications of parton distributions are small. The intrinsic structure of individual nucleons is evidently not very much affected by nuclear binding. In particular, there is no evidence for a significant increase of the quark or gluon correlation length in bound nucleons.

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M. Vänttinen, G. Piller, L. Mankiewicz, W. Weise, K. J. Eskola. 1998-08-14. Nuclear Quark and Gluon Distributions in Coordinate Space. https://doi.org/10.1007/s100500050189

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