Ion-source and LEBT issues with the front-end systems for the Spallation Neutron Source Page: 4 of 19
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
removal of the parasitic electron population from the extracted negative ions, formation of a low-
emittance ion beam, and emittance conservation. This paper discusses these issues in detail and
highlights key experimental results obtained so far with Ion Source, LEBT, and the first of four
Table 1. FES Key Performance Parameters
Ion species H-
Output energy (MeV) 2.5
H- peak current:
MEBT output (mA) 38
Nominal ion-source output (mA) 50
Output normalized transverse rms emittance (,g mm mrad) 0.27
Output normalized longitudinal rms emittance (,g MeV deg) 0.126
Macro pulse length (ms) 1
Duty factor (%) 6
Repetition rate (Hertz) 60
LEBT rise, fall time (ns) 50
MEBT rise, fall time (ns) 10
Off/on beam-current ratio 10-4
2. Ion Source Design
The H-Ion Source and LEBT are shown in Fig. 2. The source plasma is sustained by pulsed
2-MHz rf power that is conducted to an internal rf antenna through a transformer-based
impedance-matching unit and confined by a multi-cusp magnet field created by a total of 20
samarium-cobalt magnets lining the cylindrical chamber wall and 4 magnets lining the back
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Keller, R.; Cheng, D.; DiGennaro, R.; Gough, R.A.; Greer, J.; Leung, K.N. et al. Ion-source and LEBT issues with the front-end systems for the Spallation Neutron Source, article, September 1, 2001; California. (digital.library.unt.edu/ark:/67531/metadc725189/m1/4/: accessed October 23, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.