Medium-energy neutron polarimetry and spin observable for the sup 208 Pb ( rvec p , rvec n ) reaction

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5864399

Plumley, M R

Spin observables for the {sup 208}Pb({rvec p},{rvec n}){sup 208}Bi reaction were measured at scattering angles of 0{degree}, 3{degree}, 6{degree}, and 9{degree} at an incident proton beam energy of 135 Mev. The spin observables investigated are: the transverse polarization-transfer coefficient D{sub nn}{var theta}, the analyzing power A{sub Y} {var theta}, and the polarization function P{var theta}. These spin observables were obtained using a calibrated high-performance neutron polarimeter which utilizes the characteristics of n-p scattering at medium energies. Experimental results for the {sup 208}Pb({rvec p},{rvec n}){sup 208}Bi reaction are compared with plane-wave-impulse approximation (PWIA) calculations, with an overall normalization factor consistent with the eikonal approximation. The nuclear response was obtained from particle-hole Green's functions calculated in the framework of the second random-phase approximation (SRPA). Theoretical predictions for D{sub nn}{var theta} were obtained by modifying a PWIA-SRPA computer code that calculates (p,n) and (n,p) cross sections; the modifications involved computing the longitudinal and transverse spin transition densities in the PWIA. (The PWIA charge-exchange code and SPRA particle-hole Green's functions were obtained from Dr. J. Wambach of the University of Illinois). The PWIA-SRPA cross sections at 0{degree} and 3{degree} do not agree well with the data, primarily because the J{sup {pi}} = 1{sup +} Gamow-Teller giant resonance is fragmented into three peaks in the SRPA, whereas in nature it appears as a single peak. The values of D{sub nn}{var theta} calculated in the PWIA-SRPA agree quite well with what is measured, however.

• Research Organization: Kent State Univ., OH (USA)
• OSTI ID: 5864399
• Country of Publication: United States
• Language: English

Related Subjects

651920* -- Nuclear Properties & Reactions
A=190-219
Experimental
653003 -- Nuclear Theory-- Nuclear Reactions & Scattering
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANALYZING POWER
BARYON REACTIONS
BETA DECAY RADIOISOTOPES
BISMUTH 208
BISMUTH ISOTOPES
CHARGE-EXCHANGE REACTIONS
CHARGED-PARTICLE REACTIONS
COMPARATIVE EVALUATIONS
COMPUTER CODES
DATA
EIKONAL APPROXIMATION
ELECTRON CAPTURE RADIOISOTOPES
ENERGY RANGE
EXPERIMENTAL DATA
GAMOW-TELLER RULES
GIANT RESONANCE
HADRON REACTIONS
HEAVY NUCLEI
INFORMATION
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LEAD 208 TARGET
MEV RANGE
MEV RANGE 100-1000
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUMERICAL DATA
ODD-ODD NUCLEI
P CODES
POLARIMETERS
POLARIZATION
PROTON REACTIONS
RADIOISOTOPES
RESONANCE
SECONDS LIVING RADIOISOTOPES
TARGETS
THEORETICAL DATA
YEARS LIVING RADIOISOTOPES