THE PION MASS FORMULA

The often used Gell-Mann-Oakes-Renner (GMOR) mass formula for Nambu-Go ldstone (NG) bosons in QCD, such as the pions, involves the condensate [(q) over bar q], f(pi) and the quark current masses. Within the cont ext of the Global colour Model (GCM) for QCD a manifestly different fo rmula was recently found. Remarkably, Langfeld and Kettner have shown the two formulae to be equivalent. Here we note that the above recent analyses refer to the constituent pion and not the exact pion, even wi thin the GCM. Further we generalise the Langfeld-Kettner identity to i nclude the full response of the constituent quark correlators to the p resence of a non-zero (and momentum dependent) quark current mass. Res ults are reported using an effective gluon correlator from meson data fitting.