NJL model on the light cone and pion structure function Original Research Article

The NJL model is formulated on the light cone. Using the View the MathML source expansion to solve the fermionic constraint, an effective 4-Fermi Lagrangian is derived. Pionic properties are investigated using this Lagrangian, 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 cut-off scheme’, and a transverse momentum cut-off scheme. It is shown that the first one is equivalent to the covariant 3-momentum cut-off (dispersion cut-off) scheme in the equal-time formulation. As an application the structure function of the pion is studied in both regularization schemes.