Particle-in-cell techniques for the study of space charge effects in the Advanced Cryogenic Gas Stopper

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

卷:496

Article

Ringle, R.¹  Bollen, G.^1,2  Lund, K.¹  Nicoloff, C.^1,2  Schwarz, S.¹  Sumithrarachchi, C. S.¹  Villari, A. C. C.¹ 

[1] Facil Rare Isotope Beams, E Lansing, MI 48824 USA

[2] Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA

关键词: Space charge;    Gas stopper;    Particle-in-cell method;   

DOI  :  10.1016/j.nimb.2021.03.020

来源: Elsevier

【 摘 要 】

Linear gas stoppers are widely used to convert high-energy, rare-isotope beams and reaction products into low-energy beams with small transverse emittance and energy spread. Stopping of the high-energy ions is achieved through interaction with a buffer gas, typically helium, generating large quantities of He+/e- pairs. The Advanced Cryogenic Gas Stopper (ACGS) was designed for fast, efficient stopping and extraction of high-intensity, rare-isotope beams. As part of the design process, a comprehensive particle-in-cell code was developed to optimize the transport and extraction of rare isotopes from the ACGS in the presence of space charge, including He+/e(-) dynamics, buffer gas interactions including gas flow, radio-frequency carpets, and ion extraction through a nozzle or orifice. Details of the simulations are presented together with comparison to experiment when available.

【 授权许可】

Free