ππ Invariant mass spectrum in V ′ →V ππ and the f 0 (600) pole
Abstract
We consider the phenomenological description of the two pion invariant mass spectrum in the
V
′
→Vππ
decays. We study the parametrization of the amplitude involving both
S
and
D
wave contributions. From a fit to the two pion decays of the
Υ(nS)
and
Ψ(nS)
we determine the
f
0
(600)
mass and width to be
m
f
0
=528±32
MeV and
Γ
f
0
=413±45
MeV. The mass and width values we report correspond to the real and imaginary part of the S matrix pole respectively.