Intensity-dependent pion-nucleon coupling and the Wróblewski relation

We propose an intensity-dependent pion-nucleon coupling Hamiltonian within a unitary multiparticle-production model of the Auerbach-Avin-Blankenbecler-Sugar (AABS) type in which the pion field is represented by the thermal-density matrix. Using this Hamiltonian, we explain the appearance of the negative-binomial (NB) distribution for pions and the well-known empirical relation, the so-called Wróblewski relation, in which the dispersion D of the pion-multiplicity distribution is linearly related to the average multiplicity < n > : D = A < n > +B, with the coefficient A related to the vacuum energy of the pion field and < 1 . The Hamiltonian of our model is expressed linearly in terms of the generators of the SU(1, 1) group. We also find the generating function for the pion field. All higher-order thermal moments can be calculated from this function. At T = 0 it reduces to the generating function of the NB distribution. e-mail address: [email protected] e-mail address: [email protected]