Speaker
Vahabeddin Nazari
(Institute of Nuclear Physics, Polish Academy of Sciences)
Description
In a unitary multi-channel approach, precise determination of $\pi \pi$ scattering amplitudes for $D$ and $F$ waves has been presented. These scattering amplitudes are in the $I^{G}J^{PC}$ = $0^{+}2^{++}$ sector on the processes of $\pi\pi$ $\rightarrow$ $\pi\pi$, $4\pi$, $K \bar K$ and $\eta\eta$, likewise in the $I^{G}J^{PC}$ = $1^{+}3^{--}$ sector on the processes of $\pi\pi$ $\rightarrow$ $\pi\pi$, $4\pi$, $\omega\pi$ and $K \bar K$ for $D$ and $F$ waves respectively. The amplitudes were refined and re-fitted to the dispersion relations up to 1.1~GeV, and to the experimental data in the effective two pion mass from the threshold to 2.7~GeV and 1.9~GeV for $D$ and $F$ waves, respectively. Old parameterizations did not satisfy the crossing symmetry condition and did not describe the $\pi\pi$ threshold region. Moreover, a satisfactory justification regarding the controversies in the states of $f_2$ and $\rho_3$ mesons about their masses and number of states that are taken into account has been discussed and finalized.
Primary author
Vahabeddin Nazari
(Institute of Nuclear Physics, Polish Academy of Sciences)
Co-authors
Kaminski Robert
(Institute of Nuclear Physics PAN)
Petr Bydzovsky
(Nuclear Physics Institute AS CR)