Enhancing the extraction of laser-ionized beams from an arc discharge ion source volume

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:431

Article

Palenzuela, Y. Martinez^1,3  Marsh, B. A.¹  Ballof, J.^1,2  Catherall, R.¹  Chrysalidis, K.^1,4  Cocolios, T. E.³  Crepieux, B.¹  Goodacre, T. Day^1,5,6  Fedosseev, V. N.¹  Huyse, M. H.³  Larmonier, P. B.^1,7  Ramos, J. P.¹  Rothe, S.¹  Smith, J. D. A.⁸  Stora, T.¹  Van Duppen, P.³  Wilkins, S.¹ 

[1] CERN, CH-1211 Geneva 23, Switzerland

[2] Johannes Gutenberg Univ Mainz, Inst Kernchem, D-55099 Mainz, Germany

[3] Katholieke Univ Leuven, Inst Kern & Stralingsfys, B-3001 Leuven, Belgium

[4] Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany

[5] Univ Manchester, Sch Phys & Astron, Manchester M13 9PL, Lancs, England

[6] TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada

[7] Minist Affaires Etrangeres & Europeennes, 37 Quai Orsay, F-75007 Paris, France

[8] Tech X UK Ltd, Sci Tech Daresbury, Warrington, Cheshire, England

关键词: Ion source;    Resonance laser ionization;    Arc discharge ionization;    Radioactive ion beams;    Particle-in-cell simulation;   

DOI  :  10.1016/j.nimb.2018.06.006

来源: Elsevier

【 摘 要 】

The Versatile Arc Discharge and Laser Ion Source (VADLIS) is a recently established ion source for the CERN-ISOLDE radioactive ion beam facility. It offers either electron-impact ionization (VADIS-mode) or resonance laser ionization (RILIS-mode). The choice of operating mode depends on the element of interest or the required beam purity. Particle-in-cell simulations using the VSim software show that the ion extraction efficiency of the VADLIS in RILIS-mode can be improved if it is equipped with an insulated extractor plate, to which an optimal voltage can be applied. This enables optimization of the RILIS-mode ion extraction independently of the electron density. Experiments have been performed using a prototype VADLIS with an adjustable extractor plate voltage for the generation of gallium ion beams at the off-line separator as well as magnesium, molybdenum and mercury ion beams at ISOLDE. A factor > 2 increase of the VADLIS efficiency in RILIS-mode has been achieved.

【 授权许可】

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