Kinematically complete measurement of proton knockout by 220-MeV pions on /sup 12/C

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5479242

Faucett, J A

The experiment was performed with 220 MeV positive and negative pion beams incident on a natural carbon target. The final pion momentum and direction of travel were measured with a magnetic spectrometer. The ejected protons' momenta were measured with a scintillator array. Measurements were taken at scattered pion angles of 61/sup 0/, 81/sup 0/, 105/sup 0/, and 127/sup 0/ for incident positive pions and at 81/sup 0/ for incident negative pions. The protons were observed at angles over the range from 15/sup 0/ to 90/sup 0/. The final particles were observed both separately and in coincidence. The excitation of the residual nucleus was calculated for the coincidence events. Differential cross sections were obtained and displayed as pion and proton energy spectra and as angular correlations. Ratios between the positive and negative pion data were made to elucidate the differences and common features of the two reactions. The data provides detailed evidence for the quasielastic picture of pion knockout reactions which is reflected in the similarity of the spectral peak energies to those seen in pion-nucleon elastic scattering. The importance of secondary processes such as pion multiple scattering and nucleon final state interactions becomes clearer with the separation of the data according to the residual nucleus excitation energy. The coincidence cross section is found to account for about half of the (..pi../sup +/,..pi../sup +/') reaction and about half of this corresponds to quasifree knockout of the outer shell protons. For the (..pi../sup -/,..pi../sup -/'p) reaction, the secondary processes are found to pay a much more important role.

• Research Organization: Oregon Univ., Eugene (USA)
• OSTI ID: 5479242
• Country of Publication: United States
• Language: English

Related Subjects

651325* -- Nuclear Properties & Reactions
A=6-19
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR DISTRIBUTION
BARYONS
BOSONS
CARBON 12 TARGET
CHARGED-PARTICLE REACTIONS
COINCIDENCE METHODS
CORRELATIONS
COUNTING TECHNIQUES
DATA
DIRECT REACTIONS
DISTRIBUTION
ELEMENTARY PARTICLES
ENERGY RANGE
ENERGY SPECTRA
EXPERIMENTAL DATA
FERMIONS
HADRON REACTIONS
HADRONS
INFORMATION
KNOCK-OUT REACTIONS
MESON REACTIONS
MESONS
MEV RANGE
MEV RANGE 100-1000
MULTIPLE SCATTERING
NUCLEAR REACTIONS
NUCLEONS
NUMERICAL DATA
PION MINUS REACTIONS
PION PLUS REACTIONS
PION REACTIONS
PIONS
PIONS MINUS
PIONS PLUS
PROTONS
PSEUDOSCALAR MESONS
QUASI-ELASTIC SCATTERING
QUASI-FREE REACTIONS
SCATTERING
SPECTRA
TARGETS