(. pi. ,p) reactions at low excitation energy
Results of the first experimental search for the excitation of discrete final states following exclusive (..pi../sup -/,p) reactions are reported. The measurements include differential cross section at theta/sub lab/ = 25/sup 0/ for (..pi../sup +- /,p) reactions on /sup 24/Mg, /sup 27/Al, /sup 40/Ca, and /sup 58/Ni at T/sub ..pi../ = 120 MeV and (..pi../sup -/,p) on /sup 12/C at T/sub ..pi../ = 145 MeV. The (..pi../sup -/,p) reactions yield peaks with dsigma/d..cap omega..less than or equal to1 ..mu..b/sr compared to 7--22 ..mu..b/sr for peaks from (..pi../sup +/,p) reactions. The shape of the continuum in an excitation energy range of 10--40 MeV was found to be independent of pion charge and target. The ratios of (..pi../sup +/,p)/(..pi../sup -/,p) averaged over excitation energy and the ratios of the same reaction on different nuclei are presented. The magnitude of the proton yield in the low excitation continuum is more than 20 times larger for ..pi../sup +/ than for ..pi../sup -/, which supports a two-nucleon absorption model including pion charge exchange.
- Research Organization:
- Department of Physics, University of South Carolina, Columbia, South Carolina 29208
- OSTI ID:
- 5977739
- Journal Information:
- Phys. Rev. C; (United States), Vol. 35:4
- Country of Publication:
- United States
- Language:
- English
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ALUMINIUM 27 TARGET
PION MINUS REACTIONS
PION PLUS REACTIONS
CALCIUM 40 TARGET
MAGNESIUM 24 TARGET
NICKEL 58 TARGET
CAPTURE
ANGULAR DISTRIBUTION
CHARGE-EXCHANGE REACTIONS
DIFFERENTIAL CROSS SECTIONS
ENERGY LEVELS
EXCLUSIVE INTERACTIONS
EXPERIMENTAL DATA
MEV RANGE 100-1000
NUCLEAR MODELS
PROTON SPECTRA
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DATA
DISTRIBUTION
ENERGY RANGE
HADRON REACTIONS
INFORMATION
INTERACTIONS
MATHEMATICAL MODELS
MESON REACTIONS
MEV RANGE
NUCLEAR REACTIONS
NUMERICAL DATA
PARTICLE INTERACTIONS
PION REACTIONS
SPECTRA
TARGETS
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