Light-front model of the kaon electromagnetic current
  The electromagnetic form factor is extracted from both components of the electromagnetic current: J(plus) and J(minus) with a pseudo-scalar coupling of the quarks to the kaon.   In the case of J(plus) there is no pair term contribution in the Drell-Yan frame. However, J(minus) component of the electromagnetic current the pair term contribution is different from zero and is necessary include it to preserve the rotational symmetry of the current. 
J. P. B. C. de Melo and Lauro Tomio (Instituto de Fisica Teorica,   Universidade Estadual Paulista, SP, Brazil), T. Frederic...