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arXiv · 0802.3731

Non-Spherical Shapes of the Proton: Existence, Measurement and Computation

Gerald A. Miller
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Abstract

The nature of the proton wave function can be elucidated by studying the matrix elements of spin-dependent quark density operators SDDs, defined as matrix elements of density operators in proton states of definite spin-polarization. These have an infinite variety of non-spherical shapes. The matrix elements of the SDDs are closely related to specific transverse momentum dependent TMD parton distributions accessible in the angular dependence of certain semi-inclusive processes. New measurements would allow the direct exhibition of the non-spherical nature of the proton. The TMDs can be computed using lattice QCD so that the non-spherical shapes could eventually be measured experimentally and computed using fundamental theory.

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Gerald A. Miller. 2008-02-26. Non-Spherical Shapes of the Proton: Existence, Measurement and Computation. https://doi.org/10.1080/10506890802123721

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