Energy deposition accompanying pion double charge exchange: Radiochemical study of the /sup 209/Bi(. pi. /sup +/,. pi. /sup -/xn)/sup 209-x/At reactions

Journal Article · Tue Mar 01 04:00:00 EST 1983 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.27.1126· OSTI ID:6031207

Clark, J L; Haustein, P E; Ruth, T J; Hudis, J; Caretto, Jr, A A

The pion double charge exchange reactions, /sup 209/Bi(..pi../sup +/,..pi../sup -/xn)/sup 209-x/At, have been studied by radiochemical techniques for incident pion energies of 100, 180, and 300 MeV. Cross sections for the chemically separated At isotopes (A = 205--209) were determined by alpha-particle and gamma-ray spectroscopy. The contribution of secondary processes, such as /sup 209/Bi(..pi../sup +/,/sup 3,4/He)X followed by /sup 209/Bi(/sup 4/He,xn)/sup 213-x/At and /sup 209/Bi(/sup 3/He,xn)/sup 212-x/At; which mimic the double charge exchange process, was evaluated through a study of the /sup 209/Bi(..pi../sup -/,X)At reactions, since double charge exchange channels cannot contribute to At production in such ..pi../sup -/ interactions. Such secondary reactions were further characterized through target thickness studies employing 100--300 MeV ..pi../sup -/ beams. An upper limit of the cross sections for /sup 209/At production via elastic or inelastic double charge exchange below particle emission thresholds was determined to be 6 ..mu..b: a result which is roughly consistent with independent spectrometer measurements. Double charge exchange processes in which 8--50 MeV of excitation energy remains in /sup 209/At (to be later dissipated by neutron evaporation) are found to be much more probable as evidenced by the /sup 209/Bi(..pi../sup +/,..pi../sup -/xn)/sup 209-x/At, x = 2--4 excitation functions which are seen to be strongly and inversely dependent on the incident pion energy.

• Research Organization: Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973
• OSTI ID: 6031207
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 27:3; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651925* -- Nuclear Properties & Reactions
A=190-219
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA SPECTRA
ASTATINE ISOTOPES
BARYONS
BISMUTH 209 TARGET
CHARGE-EXCHANGE REACTIONS
CHARGED-PARTICLE REACTIONS
CHEMICAL ANALYSIS
CROSS SECTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EXCITATION FUNCTIONS
FERMIONS
FUNCTIONS
GAMMA SPECTRA
HADRON REACTIONS
HADRONS
ISOTOPES
MESON REACTIONS
MEV RANGE
MEV RANGE 100-1000
NEUTRONS
NUCLEAR REACTIONS
NUCLEONS
PION MINUS REACTIONS
PION PLUS REACTIONS
PION REACTIONS
QUANTITATIVE CHEMICAL ANALYSIS
RADIOCHEMICAL ANALYSIS
SPECTRA
TARGETS