Comment on ``Understanding the scalar meson quark-antiquark nonet''

Abstract

It is shown that the incomplete scalar meson nonets found by Toernqvist (T) and Toernqvist and Roos (TR), employing a new version of the Helsinki unitarised quark model, should in fact be complete, including an as yet unconfirmed light K*0 below 1 GeV (old kappa) and the established f0(1500). A detailed comparison is presented with the predictions of the Nijmegen unitarised meson model, in which two complete scalar nonets show up below 1.5 GeV. The reason for the flavour-nonet breaking found in T and TR we argue to originate in the use of coupling constants for the three-meson vertex which are not independent of flavour. Also some statements made by Toernqvist are critically reviewed.