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arXiv · 0708.2297

Densities, Parton Distributions, and Measuring the Non-Spherical Shape of the Nucleon

Gerald A. Miller
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Abstract

Spin-dependent quark densities, matrix elements of specific density operators in proton states of definite spin-polarization, indicate that the nucleon may harbor an infinite variety of non-spherical shapes. We show that these matrix elements are closely related to specific transverse momentum dependent parton distributions accessible in the angular dependence of the semi-inclusive processes electron plus proton goes to electron plus pion plus anything, and the Drell-Yan reaction proton plus proton goes to a lepton anti-lepton pair plus anything. New measurements or analyses would allow the direct exhibition of the non-spherical nature of the proton.

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Gerald A. Miller. 2007-08-16. Densities, Parton Distributions, and Measuring the Non-Spherical Shape of the Nucleon. https://doi.org/10.1103/physrevc.76.065209

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