1/Nc expansion and the spin-flavor structure of the quark interaction in the constituent quark model

Dan Pirjol, Carlos Schat

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

We study the hierarchy of the coefficients in the 1/Nc expansion for the negative parity L=1 excited baryons from the perspective of the constituent quark model. This is related to the problem of determining the spin-flavor structure of the quark interaction. The most general two-body scalar interaction between quarks contains the spin-flavor structures t1at2a,s →1•s→2 and s→1•s →2t1at2a. We show that in the limit of a zero range interaction all these structures are matched onto the same hadronic mass operator Sc2, which gives a possible explanation for the dominance of this operator in the 1/N c expansion for the L=1 states and implies that in this limit it is impossible to distinguish between these different spin-flavor structures. Modeling a finite range interaction through the exchange of a vector and pseudoscalar meson, we propose a test for the spin-flavor dependence of the quark forces. For the scalar part of the quark interaction, we find that both pion exchange and gluon exchange are compatible with the data.

Original languageEnglish
Article number114005
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume82
Issue number11
DOIs
StatePublished - 6 Dec 2010

Fingerprint

Dive into the research topics of '1/Nc expansion and the spin-flavor structure of the quark interaction in the constituent quark model'. Together they form a unique fingerprint.

Cite this