The spin-parity analysis of the data on the (p) over barp-->2pi(+)2pi(-) annihilation reaction at rest in liquid and in gaseous hydrogen at 3 bar pressure and in flight at (p) over bar momentum of similar or equal to 50 MeV/c, collected by the Obelix spectrometer at the LEAR complex of CERN, is presented. The relative branching ratios (alpha(1)(1260)-->sigmapi)/(alpha(1)(1260)-->rhopi)=0.06+/-0.05 and (pi(1300)-->sigmapi)/(pi(1300)-->rhopi)=2.2+/-0.4 are obtained. It is also shown that the inclusion of the exotic meson pi(1)(1400), J(PC) = 1(- +) , mass and width M=1.384+/-0.028, Gamma=0.378+/-0.058 GeV/c(2), in its decay to rhopi, improves the fit and some implications of these results are briefly discussed. The relative S and P-wave annihilation percentages in four charged pions at two target densities are obtained.
(p)over-barp annihilation into four charged pions at rest and in flight
DE FALCO, ALESSANDRO;PUDDU, GIOVANNA;USAI, GIANLUCA;
2004-01-01
Abstract
The spin-parity analysis of the data on the (p) over barp-->2pi(+)2pi(-) annihilation reaction at rest in liquid and in gaseous hydrogen at 3 bar pressure and in flight at (p) over bar momentum of similar or equal to 50 MeV/c, collected by the Obelix spectrometer at the LEAR complex of CERN, is presented. The relative branching ratios (alpha(1)(1260)-->sigmapi)/(alpha(1)(1260)-->rhopi)=0.06+/-0.05 and (pi(1300)-->sigmapi)/(pi(1300)-->rhopi)=2.2+/-0.4 are obtained. It is also shown that the inclusion of the exotic meson pi(1)(1400), J(PC) = 1(- +) , mass and width M=1.384+/-0.028, Gamma=0.378+/-0.058 GeV/c(2), in its decay to rhopi, improves the fit and some implications of these results are briefly discussed. The relative S and P-wave annihilation percentages in four charged pions at two target densities are obtained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.