Remarks on the Θ(1540) pentaquark -: art. no. 116001

Additional broader I=0 states in the KN channel near Theta(+)(1540) are expected in many models, making the absence of any signature in the K+-deuteron scattering data even more puzzling. In an ideal three-body picture the Theta is viewed as two compact ud(1)ud(2) (3) over bar color diquarks and an (s) over bar quark. A QCD-type inequality involving m(Theta(+)), m(Lambda), the mass of the Lambda(1/2(-)) L=1 excitation, and that of a new I=0 tetraquark vector meson then follows. The inequality suggests a very light new vector meson, and is violated. We note that associated production of the pentaquark with another quadriquark or antipentaquark may be favored. This along with some estimates of the actual production cross sections suggest that the Theta can be found in BaBar or Belle e(+)-e(-) colliders.