Reduction of the thermoionic current in the laser ion source

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 126; no. 1; pp. 92 - 94
• Main Authors: Beznosjuck, V.I., Fedorov, D.V., Orlov, S.Yu, Seliverstov, M.D., Tikhonov, V.I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.1997
• Subjects: Laser ion source; Laser ion source; 29.25 Cy
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/S0168-583X(96)01020-8

One of the unsolved problems of laser ion-source application is the reduction of the background from the thermoionic current arising in the laser ion source (LIS) at high temperature. This background decreases the selectivity of the laser ionisation and hinders strongly the possibility to investigate nuclei far from stability. In order to avoid or, at least, to reduce the background to lower level it is suggested to use sources with a modified inner surface. The modifications are carried out in a special device and consist in multi-stage treatment of the LIS tube, made of Ta, with various species. The detailed description of the technology is presented and the first results are discussed.