Optical Cerenkov measurements of emittance growth in the Advanced Test Accelerator beam under laser ion-guiding

Author

Chong, Y.P. ; Deadrick, F.J. ; Hirzel, D.G. ; Kallman, J.S. ; Lee, P. ; Poulter, J.F. ; Rivera, W.E. ; Stephan, P.L. ; Weir, J.T.

Author_Institution

Lawrence Livermore Nat. Lab., CA, USA

fYear

1989

fDate

20-23 Mar 1989

Firstpage

1495

Abstract

A new beam profile diagnostic using optical Cernekov radiation from a quartz foil has been deployed at the Advanced Test Accelerator (ATA). Quartz performs better than previously tested foils (titanium and Kapton) in terms of damage threshold. The emission intensity from quartz is over an order of magnitude brighter than that from graphite foil. Data were taken at the beginning, middle, and end of ATA, i.e. at 3.8 MeV (cell 15), 22.5 MeV (cell 90), and 43 MeV (11 m beyond the end). Profile measurements of the ion-focused beam showed emittance growth through the pulse. Double-Gaussian fits to the radial profile were often superior to single-Gaussian fits and showed that a large beam dominated the second half of the pulse. This was observed for currents of 1, 3, and 7 kA at the accelerator output and at cell 15 for the 3-kA case. The dependence of emittance growth on several parameters was studied

Keywords

beam handling equipment; beam handling techniques; focusing; particle accelerator accessories; particle accelerators; 1 kA; 22.5 MeV; 3 kA; 3.8 MeV; 43 MeV; 7 kA; Advanced Test Accelerator beam; Kapton foils; Ti foils; beam profile diagnostic; damage threshold; double-Gaussian fits; emission intensity; emittance growth; graphite foil; ion-focused beam; laser ion-guiding; optical Cernekov radiation; quartz foil; radial profile; single-Gaussian fits; Cameras; Free electron lasers; Optical saturation; Optical variables control; Particle beams; Pulse measurements; Radiation detectors; Stimulated emission; Testing; Titanium;

fLanguage

English

Publisher

ieee

Conference_Titel

Particle Accelerator Conference, 1989. Accelerator Science and Technology., Proceedings of the 1989 IEEE

Conference_Location

Chicago, IL

Type

conf

DOI

10.1109/PAC.1989.73491

Filename

73491