Reaction mechanism in the {sup 20}Ne+{sup 59}Co system at 3-7 MeV/nucleon, and observation of entrance-channel mass-asymmetry of the incomplete fusion fraction

Journal Article · Sun May 15 00:00:00 EDT 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.054604· OSTI ID:21502475

Singh, D ^[1]; Ali, R; Afzal Ansari, M ^[2]; Tomar, B S ^[3]; Rashid, M H; Guin, R; Das, S K ^[4]

---

1. Nuclear Physics Division, Inter University Accelerator Centre, New Delhi-110067 (India)
2. Nuclear Physics Laboratory, Department of Physics, Aligarh Muslim University, Aligarh-202002 (India)
3. Radio-chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085 (India)
4. Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata-700064 (India)

Incomplete fusion of {sup 20}Ne with {sup 59}Co has been investigated at 3-7 MeV/nucleon using the measurement and analysis of excitation functions. The recoil-catcher technique followed by offline gamma-ray spectroscopy has been employed. Evaporation residues are found to have contributions from precursor decays, which have been separated out from the measured cumulative cross sections of evaporation residues. Measured independent cross sections are compared with PACE-2 predictions. The PACE-2 calculations are carried out for evaporation residues formed in complete fusion (CF), and the parameters are optimized so as to reproduce the cross section of evaporation residues produced exclusively in CF, e.g., xn and pxn products. With these parameters, the predicted CF cross sections for alpha emission products are calculated. Any substantial enhancement in the experimental cross section over the PACE-2 prediction is taken as a signature of incomplete fusion (ICF). The analysis indicates the occurrence of incomplete fusion involving the breakup of {sup 20}Ne into {sup 16}O + {sup 4}He and/or {sup 12}C + {sup 8}Be(2{alpha}) followed by fusion of one of the fragments with the target nucleus {sup 59}Co. These data also suggest that the probability of incomplete fusion increases with the projectile energy. Moreover, the ICF probability is found to increase with entrance-channel mass-asymmetry of the projectile-target systems.

• OSTI ID: 21502475
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 83, Issue 5; Other Information: DOI: 10.1103/PhysRevC.83.054604; (c) 2011 American Institute of Physics; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ASYMMETRY
BERYLLIUM 8
CARBON 12
COBALT 59
EMISSION
EVAPORATION
EXCITATION FUNCTIONS
FORECASTING
GAMMA SPECTROSCOPY
HELIUM 4
MASS
MEV RANGE 01-10
NEON 20
NUCLEAR REACTIONS
NUCLEONS
OXYGEN 16
PRECURSOR
REACTION KINETICS
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
BARYONS
BERYLLIUM ISOTOPES
CARBON ISOTOPES
COBALT ISOTOPES
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EVEN-EVEN NUCLEI
FERMIONS
FUNCTIONS
HADRONS
HELIUM ISOTOPES
INTERMEDIATE MASS NUCLEI
ISOTOPES
KINETICS
LIGHT NUCLEI
MEV RANGE
NEON ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
OXYGEN ISOTOPES
PHASE TRANSFORMATIONS
RADIOISOTOPES
SPECTROSCOPY
STABLE ISOTOPES