Study of transfer and breakup reactions with the plastic box

Conference · Sat Dec 01 04:00:00 EST 1984

OSTI ID:5920003

Stokstad, R G; Albiston, C R; Bantel, M; Chan, Y; Countryman, P J; Gazes, S; Harvey, B G; Homeyer, H; Murphy, M J; Tserruya, I

The study of transfer reactions with heavy-ion projectiles is complicated by the frequent presence of three or more nuclei in the final state. One prolific source of three-body reactions is the production of a primary ejectile in an excited state above a particle threshold. A subset of transfer reactions, viz., those producing ejectiles in bound states, can be identified experimentally. This has been accomplished with a 4..pi.. detector constructed of one-millimeter-thick scintillator paddles of dimension 20 cm x 20 cm. The paddles are arranged in the form of a cube centered around the target with small entrance and exit apertures for the beam and the projectile-like fragments, (PLF). The detection of a light particle (e.g., a proton or an alpha particle) in coincidence with a PLF indicates a breakup reaction. The absence of any such coincidence indicates a reaction in which all the charge lost by the projectile was transferred to the target. With this technique we have studied the transfer and breakup reactions induced by 220 and 341 MeV /sup 20/Ne ions on a gold target. Ejectiles from Li to Ne have been measured at several scattering angles. The absolute cross sections, angular distributions and energy spectra for the transfer and breakup reactions are presented. Relatively large cross sections are observed for the complete transfer of up to seven units of charge (i.e., a nitrogen nucleus). The relatively large probabilities for ejectiles to be produced in particle-bound states suggest that on the average, most of the excitation energy in a collision resides in the heavy fragment when mass is transferred from the lighter to the heavier fragment. The gross features and trends in the energy spectra for transfer and breakup reactions are similar. 20 references.

• Research Organization: Lawrence Berkeley Lab., CA (USA); Stanford Univ., CA (USA). Dept. of Physics; Hahn-Meitner-Institut fuer Kernforschung Berlin G.m.b.H. (Germany, F.R.)
• DOE Contract Number: AM03-76SF00326; AC03-76SF00098
• OSTI ID: 5920003
• Report Number(s): LBL-18240-Rev.; CONF-841259-3-Rev.; ON: DE85007471
• 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
ANGULAR DISTRIBUTION
BREAKUP REACTIONS
CHARGED-PARTICLE REACTIONS
COINCIDENCE METHODS
COUNTING TECHNIQUES
CROSS SECTIONS
DATA
DIRECT REACTIONS
DISTRIBUTION
ENERGY SPECTRA
EXPERIMENTAL DATA
FOUR-PI COUNTING
GOLD 197 TARGET
HEAVY ION REACTIONS
INFORMATION
MEASURING INSTRUMENTS
NEON 20 REACTIONS
NUCLEAR FRAGMENTS
NUCLEAR REACTIONS
NUMERICAL DATA
PLASTIC SCINTILLATION DETECTORS
RADIATION DETECTORS
SCINTILLATION COUNTERS
SOLID SCINTILLATION DETECTORS
SPECTRA
TARGETS
TRANSFER REACTIONS