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arXiv · hep-ph/0410304

Are There Diquarks in the Nucleon?

M. Cristoforetti·P. Faccioli·G. Ripka·M. Traini
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Abstract

This work is devoted to the study of diquark correlations inside the nucleon. We analyze some matrix elements which encode information about the non-perturbative forces, in different color anti-triplet diquark channels. We suggest a lattice calculation to check the quark-diquark picture and clarify the role of instanton-mediated interactions. We study in detail the physical properties of the 0+ diquark, using the Random Instanton Liquid Model. We find that instanton forces are sufficiently strong to form a diquark bound-state, with a mass of ~500 MeV, which is compatible with earlier estimates. We also compute its electro-magnetic form factor and find that the diquark is a broad object, with a size comparable with that of the proton.

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M. Cristoforetti, P. Faccioli, G. Ripka, M. Traini. 2005-05-23. Are There Diquarks in the Nucleon?. https://doi.org/10.1103/physrevd.71.114010

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