Populations of excited states and reaction mechanisms in the emission of complex fragments for collisions of sup 58 Ni+ sup 58 Ni at 11 MeV/nucleon

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Physical Review, C (Nuclear Physics); (USA)

DOI:https://doi.org/10.1103/PhysRevC.43.2689· OSTI ID:5663318

Gomez del Campo, J; Auble, R L; Beene, J R; Halbert, M L; Kim, H J ^[1]; D'Onofrio, A ^[2]; Charvet, J L ^[3]

---

1. Oak Ridge National Laboratory, Oak Ridge, TN (USA)
2. Istituto Nazionale di Fisica Nucleare, 80125 Napoli, Naples (Italy)
3. Service de Physique Nucleaire, Basse Energie, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette, CEDEX (France)

Cross sections for emission of complex fragments ({ital Z}{gt}2) in their ground and excited states are presented for the reaction {sup 58}Ni+{sup 58}Ni at a bombarding energy of 630 MeV. Measurements of energy spectra, angular distributions, and angle-integrated cross sections were made for fragments of {ital Z}=4 to 20. {gamma} rays emitted in coincidence with the fragments were measured in a 4{pi} geometry using 62 NaI detectors and 8 Compton-suppressed germanium detectors. Data presented are mostly for the cross sections extracted by {gamma}-ray techniques. A simple statistical approach to associate the ratio of cross sections for excited states and ground states to the temperature of the emitter fails to give the expected temperatures. However, it is shown that this is mostly due to the fact that the fragments that {gamma} decay are secondary fragments produced by particle decay of the primary fragments. A Hauser-Feshbach analysis accounts well for the fragment cross sections, energy spectra, and extracted temperatures, provided that evaporation from the primary fragments is included.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5663318
• Journal Information: Physical Review, C (Nuclear Physics); (USA), Journal Name: Physical Review, C (Nuclear Physics); (USA) Vol. 43:6; ISSN 0556-2813; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651520* -- Nuclear Properties & Reactions
A=39-58
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR DISTRIBUTION
CHARGED-PARTICLE REACTIONS
COINCIDENCE SPECTROMETRY
CROSS SECTIONS
DATA
DECAY
DISTRIBUTION
ENERGY RANGE
EXPERIMENTAL DATA
GAMMA SPECTROSCOPY
HAUSER-FESHBACH THEORY
HEAVY ION EMISSION DECAY
HEAVY ION REACTIONS
INFORMATION
MEV RANGE
MEV RANGE 100-1000
NICKEL 58 REACTIONS
NICKEL 58 TARGET
NUCLEAR DECAY
NUCLEAR FRAGMENTATION
NUCLEAR REACTIONS
NUCLEAR THEORY
NUMERICAL DATA
SPECTROSCOPY
TARGETS