E. T. Boschitz

π+−16O elastic scattering from 80 to 340 MeV

Abstract We present preliminary results for π + − 16 O elastic scattering at 79, 114, 16, 240 and 343 MeV. Statistical uncertainties are about 5% for angular bins of 1.5°. The data are compared to a first-order momentum-space optical model calculation.

A comparison of π+ and π− scattering from 16O and 18O at the (3, 3) resonance

Abstract Angular distributions were measured for π + and π − scattering from 16 O and 18 O at 163 MeV. The π + elastic cross sections are similar but significant differences are observed between the π − elastic cross sections confirming the expected greater sensitivity of the π − to the 2 extra neutrons in 18 O. Appreciable differences between π + and π − are also observed for the inelastic scattering to the 2 + state at 1.98 MeV and the 3 − state at 5.09 MeV.

The elastic scattering of π+ and π− by 16O and 40Ca across the (3,3) resonance

Abstract Results are reported for the elastic scattering of π + and π − by 16 O and 40 Ca between 115 MeV and 240 MeV. Large differences between the π + and π − cross sections are observed up to large angles which are substantially explained by simple Coulomb effects.

The SIN high resolution pion channel and spectrometer

The optical properties of the SIN high resolution pion channel and spectrometer are briefly reviewed. The operation of the whole system, including detectors and data acquisition is then described. Finally the tune-up method and the actual performances are given.

Elastic scattering of positive pions by 16O between 80 and 340 MeV

Abstract Angular distributions of cross sections for π + elastic scattering by 16 O have been measured between 14° and 138° at five energies (79, 114, 163, 240 and 343 MeV). They are compared to calculations using a first-order static model and an isobar doorway model. Phase-shift analyses have been done using the theoretical inputs as guidelines. The validity of these models is discussed.

Full angular distribution of the analysing power in p elastic scattering at 697 MeV/c

Abstract Full angular distributions of the differential cross-section dσ/dμ and of the analysing power Ay in p p elastic scattering have been measured at 697 MeV/c. The results of Ay are compared with the predictions of various theoretical models.

Measurement of the analyzing power in elastic scattering at 439 and 544 MeV/c

Abstract The angular distributions of the analyzing power Ay and of the differential cross section d σ/ d Ω in p p elastic scattering have been measured at 439 and 544 MeV/c. The results of Ay are compared with various theoretical models.

Neutron and proton components of nuclear transitions in pion inelastic scattering on 26Mg

Abstract The elastic and inelastic scattering of 180 MeV positive and negative pions from 26 Mg has been measured. From these data the ratios of neutron and proton nuclear transition matrix elements have been determined for the first and second excited states. These ratios are compared with those obtained from electromagnetic transitions in mirror nuclei and with shell model predictions.

Measurements of the vector analyzing poweriT11in theπd→elastic scattering reaction between 117 and 325 MeV

The vector analyzing power iT/sub 11/ has been measured for the ..pi..d elastic scattering reaction at 12 incident pion energies between 117 and 325 MeV, using a vector polarized deuteron target. The results cover an average of 14 angles per incident pion energy. A detailed comparison with existing Faddeev calculations is made. The effect of including dibaryon resonances with one of these predictions is investigated.

Pionic excitation of giant resonances in 89Y

Abstract Inelastic scattering of π+ and π− exhibits strongly excited giant resonance structures. Besides the giant quadrupole resonance centered around 14 MeV, structures are observed at 16.8 MeV which can be fitted with a mixing of L=0 and L=1, and around 25 MeV (E x = 110A − 1 3 ) .