The electrostatic separator VASSILISSA Performance and experimental results

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 126; no. 1; pp. 329 - 333
• Main Authors: Yeremin, A.V., Bogdanov, D.D., Chepigin, V.I., Gorshkov, V.A., Kabachenko, A.P., Malyshev, O.N., Popeko, A.G., Sagaidak, R.N., Ter-Akopian, G.M., Lavrentjev, A.Yu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.1997
• Subjects: Complete fusion reactions; Compound nuclei; Heavy ions; Recoil separators; α radioactivity; Heavy ions; Compound nuclei; 29.30.−h; 23.60.+e; 25.70.−z; α radioactivity; Complete fusion reactions; Recoil separators
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/S0168-583X(96)01002-6

Within the past seven years the electrostatic separator VASSILISSA [A.V. Yeremin et al., Nucl. Instr. and Meth. A 274 (1989) 528; A 350 (1994) 608] has been used for the investigations of evaporation residues (ER) produced in heavy-ion induced complete fusion reactions. Two types of such studies were of specific interest to us. These are the synthesis of heavy ( Z ≥ 100) nuclides and investigations of heavy-ion fusion reactions leading to formation of neutron-deficient nuclei with Z ≥ 82 and high excitation energy ( 60 MeV ≤ E ∗ ≤ 200 MeV ). In the course of the experimental work the optimization of the ion-optical and other systems of the separator including the improvements in the focal plane detector system has been made. As a result, the separation efficiency values ranging from 3 to 30% were achieved for ER's produced in the reactions with heavy ions from 12C to 48Ti. The suppression factors > 10 19 for the full energy beam particles and > 10 4 for multinucleon transfer reaction products were achieved. The results of the performed experiments illuminating the separator performance and future plans of the separator upgrade are briefly presented.