The spin-parity analysis of the data on the pbar p → 2π+ 2π− annihilation reaction at rest in liquid and in gaseous hydrogen at 3 bar pressure and in flight at p momentum of ~ 50 MeV/c, collected by the Obelix spectrometer at the LEAR complex of CERN, is presented. The relative branching ratios (a1(1260) → σπ)/(a1(1260) → ρπ) = 0.06 ± 0.05 and (π(1300) → σπ)/(π(1300) → ρπ) = 2.2 ± 0.4 are obtained. It is also shown that the inclusion of the exotic meson π1(1400), JPC= 1−+, mass and width M = 1.384 ± 0.028, Γ = 0.378 ± 0.058 GeV/c2, in its decay to ρπ, 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. SALVINI, V.I. TRETYAK, V. FILIPPINI, A. FONTANA, P. MONTAGNA, A. PANZARASA, et al. (2004). pbar p annihilation into four charged pions at rest and in flight. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS, 35, 21-33 [10.1140/epjc/s2004-01811-8].
pbar p annihilation into four charged pions at rest and in flight
BARGIOTTI, MARIANNE;BERTIN, ANTONIO;CAPPONI, MARCO;CARBONE, ANGELO;DE CASTRO, STEFANO;FABBRI, LAURA;FACCIOLI, PIETRO;GALLI, DOMENICO;GRIMALDI, FILIPPO;MASSA, IGNAZIO GIACOMO;PICCININI, MAURIZIO;SEMPRINI CESARI, NICOLA;VILLA, MAURO;VITALE, ANTONIO;ZOCCOLI, ANTONIO;
2004
Abstract
The spin-parity analysis of the data on the pbar p → 2π+ 2π− annihilation reaction at rest in liquid and in gaseous hydrogen at 3 bar pressure and in flight at p momentum of ~ 50 MeV/c, collected by the Obelix spectrometer at the LEAR complex of CERN, is presented. The relative branching ratios (a1(1260) → σπ)/(a1(1260) → ρπ) = 0.06 ± 0.05 and (π(1300) → σπ)/(π(1300) → ρπ) = 2.2 ± 0.4 are obtained. It is also shown that the inclusion of the exotic meson π1(1400), JPC= 1−+, mass and width M = 1.384 ± 0.028, Γ = 0.378 ± 0.058 GeV/c2, in its decay to ρπ, 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.
