2023 Impact factor 2.6
Hadrons and Nuclei
Eur. Phys. J. A 16, 229-258 (2003)
DOI: 10.1140/epja/i2002-10068-x

$\mth{K}$-matrix analysis of the $\mth{(IJ^{PC}=00^{++})}$-wave in the mass region below 1900 MeV

V.V. Anisovich and A.V. Sarantsev

St. Petersburg Nuclear Physics Institute, Gatchina 188350, Russia

anisovic@thd.pnpi.spb.ru

(Received: 14 May 2002 / Revised version: 02 August 2002 / Published online: 11 February 2003)

Abstract
We present the results of the current analysis of the partial wave IJPC =00++ based on the available data for meson spectra ( $\pi\pi , K\bar K , \eta\eta , \eta\eta', \pi\pi \pi\pi $). In the framework of the K-matrix approach, the analytical amplitude has been reconstructed in the mass region 280 MeV $< \sqrt s
<1900$ MeV. The following scalar-isoscalar states are seen: comparatively narrow resonances f0(980), f0(1300), f0(1500), f0(1750) and the broad state f0(1200-1600). The positions of the amplitude poles (masses and total widths of the resonances) are determined as well as pole residues (partial widths to meson channels $\pi\pi , K\bar K , \eta\eta , \eta\eta', \pi\pi \pi\pi $ ). The fitted amplitude gives us the positions of the K-matrix poles (bare states) and the values of bare-state couplings to meson channels thus allowing the quark-antiquark nonet classification of bare states. On the basis of the obtained partial widths to the channels $\pi\pi , K\bar K ,
\eta\eta , \eta\eta' $ , we estimate the quark/gluonium content of f0(980), f0(1300), f0(1500), f0(1750), f0(1200-1600). For f0(980), f0(1300), f0(1500) and f0(1750), their partial widths testify the $q\bar q$ origin of these mesons though being unable to provide precise evaluation of the possible admixture of the gluonium component in these resonances. The ratios of the decay coupling constants for the f0(1200-1600) support the idea about the gluonium nature of this broad state.

PACS
12.39.Mk - Glueball and nonstandard multi-quark/gluon states.
12.38.-t - Quantum chromodynamics.
14.40.-n - Mesons.

© Società Italiana di Fisica, Springer-Verlag 2003