LHC as π p and π π collider

Se p 20 07 Physics of η ′ → π + π − η and η ′ → π + π − π 0 decays

The article describes experimental status of the η ′ → π+π−η and η ′ → π+π−π0 decays. A theoretical framework used for description of the decays mechanism is also reviewed. The possibilities for the measurements with WASA-at-COSY are mentioned.

0 Observation of the φ → π + π − π + π − Decay

Using 11.6 pb of data collected in the energy range 0.984–1.06 GeV by CMD-2 at VEPP-2M, the cross section of the reaction e+e− → π+π−π+π− has been studied. For the first time an interference pattern was observed in the energy dependence of the cross section near the φ meson. The branching ratio of the φ → π+π−π+π− decay double suppressed by the G-parity and OZI rule is measured Br(φ → ππππ) = (...

0 → π + π − π 0 feasibility studies

Search for direct CP violating charge asymmetries in K ± → π ± π + π − and K ± → π ± π 0 π 0 decays

A measurement of the direct CP violating charge asymmetries of the Dalitz plot linear slopes Ag = (g + − g)/(g + g) in K → πππ and K → πππ decays by the NA48/2 experiment at CERN SPS is presented. A new technique of asymmetry measurement involving simultaneous K and K beams and a large data sample collected allowed a result of an unprecedented precision. The charge asymmetries were measured to ...

Se p 19 99 Production of the π − , π 0 in the reaction d ( e , pp ) e ′ π − π 0

Recently, the differential yield and target asymmetry of the reaction d(e, pp)eπ on the tensor polarized deuterium target have been presented in [1, 2], where the experimental procedure and basic assumption were described. A precise treatment of this reaction needs to investigate the reaction channels with an additional neutral pion production as a background to the leading reaction of a single...