ADDENDUM to the end of the paper
At pg 14. From the end of the second paragraph of Conclusions.
A nice confirmation of this scenario is coming from a recent L3 experiment [22] where for the first time , the E/iota state is observed in Gamma Gamma collision and its two-photon width is measured. Because in Gamma Gamma interactions, production of a pure gluon state is expected to be small with respect to a qbarq state, the absence or suppression of a state in Gamma Gamma collisions is a good argument in favor of exotics or at least of a large coupling to gluons. This means that Gamma Gamma interactions are a nice filter for E/iota structure.
The states observed in ref[22] are f1(12850), f1(1420) and eta at 1481+/- 12MeV in KKpi channel and only f1(1285) in etapipi channel.
This points
to the fact that indeed the lower mass component
of E/iota structure (etaL [9]) is the exotic
state which can be seen (pbarp,
J/Psi decay) in KKpi or etapipi
( for example at m=1409MeV in pbarp Crystal Barrel [7]) and
is absent in Gamma Gamma collisions. The higher mass component is a
mainly sbars member of the
pseudoscalar nonet and therefore seen
only in KKpi
channel and not in etapipi.
The scalar resonance found in the K+K-pi+pi-
system could be identified with another decay mode of the
f0(1710), although the width
found here (Gamma=0.267 GeV) is somewhat larger. Its nature has not yet been
established and interpretation ranging from glueball to molecular state has been
suggested [9,10]. The glueball candidacy can
be indicated also by the absence of
the resonance signal in process
Gamma Gamma à
pi+pi- as has been demonstrated in a recent work [23].
The decay mode of the f0(1710) in Kkpipi
final state was predicted in ref. [19] and [20], in the framework of K*K*
bound states or vector-meson molecules, both models giving the K*K*
as the dominant isobar composition of this final state. Although a
resonant behavior of the K*K* system cannot be excluded, this contribution
turned out, in the present analysis, to be very small
and the
only K* produced are
those from E/iota subsystem ( only charged K* ). This is in agreement with the
central production of K*K* from the WA76 experiment [21], in which the K*K*
contribution was interpreted as a non-resonant threshold enhancement
and in disagreement with [24] where the peak of K*K* near the threshold
is fitted with a very broad (width =500 MeV) pseudoscalar of mass =1800MeV.
In this work, the dominant isobar decomposition of the KKpipi decay mode of the f0(1710) turned out to be f0(1370)(pipi)S, where f0(1370) is a broad KK scalar state with mass 1.399 +/- 0.010 GeV and width 0.197 +/- 0.030 GeV. This is in agreement with the decay mode ( 0++ à 0++ ,0++ ) of the f0(1710) found by [25] in radial J/Psi decay into 4pi.
More Ref.
[22] L3 Collaboration,
Phys. Lett. B 501 (2001)
[23] ALEPH Collaboration, R. Barante et al,
Phys. Lett. B 472 (2000)189
[24] BES Collaboration, J.Z. Bai et al,
Phys. Lett. B472(2000)200
[25] BES Collaboration, J.Z. Bai et al, Phys. Lett. B472(2000)207.