Njl Model on the Light Cone and Pion Structure Function *
نویسندگان
چکیده
The NJL model is formulated on the light cone. Using the 1/N expansion to solve the fermionic constraint, an effective 4-fermi la-grangian is derived. Pionic properties are investigated using this la-grangian, and the formal equivalence to the equal-time formulation is demonstrated. Two regularization schemes in terms of light-cone variables are discussed: An extension of the 'invariant mass cutoff scheme', and a transverse momentum cutoff scheme. It is shown that the first one is equivalent to the covariant 3-momentum cutoff (dispersion cutoff) scheme in the equal-time formulation. As an application the structure function of the pion is studied in both regularization schemes.
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