Pion scattering to 8/sup -/ stretched states in /sup 60/Ni

Technical Report · Tue Mar 01 04:00:00 EST 1988

DOI:https://doi.org/10.2172/5123203· OSTI ID:5123203

Clausen, B L

Using the Energetic Pion Channel and Spectrometer at the Los Alamos Meson Physics Facility, differential cross sections for pion scattering were measured for ten previously known J/sup ..pi../ = 8/sup /minus// stretched states in /sup 60/Ni. A possible new pure isoscalar stretched state was also found. The data were taken near the /DELTA//sub 3,3/-resonance using 162 MeV incident pions and scattering angles of 65/degree/, 80/degree/, and 90/degree/ for ..pi../sup +/ and 65/degree/ and 80/degree/ for ..pi../sup /minus//. The analysis of the /sup 60/Ni data found that the use of Woods-Saxon wave functions in the theoretical calculations gave much better agreement with data than the use of the usual harmonic oscillator wave functions. The WS theory gave better predictions of: the angle at which the ..pi../sup /minus// and ..pi../sup +/ angular distributions are maximum, the ratios of ..pi../sup /minus// to ..pi../sup +/ cross sections for pure isovector states (which were much larger than unity), and the absolute size of the cross sections for all states (so that the normalization factor necessary to arrive at agreement of theory with data was closer to unity). The theoretical calculations used the distorted wave impulse approximation, including new methods for unbound states. The sensitivities of the calculations to input parameters were investigated. This analysis using WS wave functions was extended to five other nuclei (/sup 12/C, /sup 14/C, /sup 16/O, /sup 28/Si, and /sup 54/Fe) on which both pion scattering and electron scattering have been done. A significant improvement in arriving at a normalization factor close to unity was found when WS wave functions were consistently used for analyzing both pion and electron inelastic scattering data. 101 refs., 26 figs., 13 tabs.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5123203
• Report Number(s): LA-11213-T; ON: DE88006450
• Country of Publication: United States
• Language: English

Related Subjects

651520* -- Nuclear Properties & Reactions
A=39-58
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BEAM MONITORING
BORN APPROXIMATION
CHARGED PARTICLE DETECTION
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DATA
DATA ACQUISITION SYSTEMS
DATA ANALYSIS
DETECTION
ENERGY LEVELS
ENERGY SPECTRA
EXCITED STATES
EXPERIMENTAL DATA
FUNCTIONS
HADRON REACTIONS
INELASTIC SCATTERING
INFORMATION
MEASURING INSTRUMENTS
MESON REACTIONS
MONITORING
NICKEL 60 TARGET
NUCLEAR POTENTIAL
NUCLEAR REACTIONS
NUMERICAL DATA
PION DETECTION
PION REACTIONS
POTENTIALS
RADIATION DETECTION
SCATTERING
SPECTRA
SPECTROMETERS
TARGETS
WAVE FUNCTIONS
WOODS-SAXON POTENTIAL