H − magnetic beam extractors design for the KOMAC project

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 474; no. 1; pp. 1 - 9
• Main Authors: Ahn, H.E., Choi, B.H., Ha, J.H.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 21.11.2001
• Subjects: Beam dynamics; Beam extraction; Beam transport; Linear accelerator; Simulation; Stripper superconducting magnet; Stripper superconducting magnet; 41.85.−p; Simulation; Beam extraction; Beam transport; 29.27.−a; 85.25.−j; Beam dynamics; 07.05.−t; Linear accelerator
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(01)00868-3

Complete design specifications for 260 MeV H − beam extractors are presented. The extractor employs a novel design of a stripper magnet which separately handles both the stripping of the H − beam and the bending of the unextracted H − beam. The design objective of the extractor is to partially extract a negative hydrogen ion (H −) beam at 260 MeV from the main linac where both protons (H +) and negative hydrogen ions are accelerated up to 1 GeV . Since the extractor adopts the magnetic stripping method, emittance growth is unavoidable for the extracted beam. However, the unextracted H − beam returns to the main linac with no change in the beam profile. The main features of this extractor are: (1) its ability to regulate the intensity of the extracted beam and (2) the nondestructive effect on the profile of the H − downstream beam. These extractors will be utilized for the Korea Multi-purpose Accelerator Complex (KOMAC) linear accelerator of 1 GeV cw proton (H +)/negative hydrogen (H −) beams with an intensity of 20 mA .