F. Palombo

Scintillation hodoscopes for time-of-flight measurements

Abstract The performances of the TOF scintillation counters used in the SIGMA-AIAKS spectrometer are presented. The counters, made of NE110, are 150, 65 and 10 cm long, 10 cm wide and 1.5 cm thick. The time resolutions for minimum ionizing particles have been measured to be σ t = 0.18 ns, 0.14 ns and 0.11 ns respectively. The main contribution to the resolution is given by the photoe collection statistics determined by the decay time of the scintillator and the difference of the optical paths in the counter. The scintillation counters, assembled into hodoscopes of 1.5 × 3.2 m 2 and 0.65 × 0.8 m 2 are used for identification of particles through the TOF. The algorithms of off-line data processing are also presented.

Fe-scintillator hodoscopic hadron calorimeter

Abstract A Fe-scintillator hodoscopic hadron calorimeter is described. It consists of independent sections, each containing four total absorption counters 20×20 cm 2 in cross section. The energy resolution for hadrons in the energy range E = 4–40 GeV is σ E / E = 0.02 + 0.52/√ E and the mean space resolution is ∼ 2 cm at 40 GeV.

Determination of the branching ratio ofρ0→+μ− in the coherent dissociation π−→μ+μ−π− and π−→π+π−π−

AbstractIn the diffraction dissociation of π− into μ+μ−π− on a Cu nucleus at 50 GeV/c, the cross section

Cross sections of backward proton production in 40 GeV/c π−(K−,p)−A interactions

\sigma _{\mu ^ + \mu ^ - \pi ^ - }

Determination of the branching ratio of? 0?+- in the coherent dissociation p-?+-p- and p-?p+p-p-

for the 1+S(ρ0π) wave was measured. The branching ratio of ρ0→μ+μ− could be calculated from the ratio of this and the corresponding cross sections in the diffraction dissociation of π− into π+π−π−. The obtained value

Direct observation of pi2(1680) in the rho0pi- system

BR_{\rho ^0 \to \mu ^ + \mu ^ - } = (4.6 \pm 0.2_{stat^ \pm } \pm 0.2_{syst} )10^{ - 5}