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Title: Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique

Abstract

A common issue encountered in photoemission electron sources used in electron accelerators is the transverse inhomogeneity of the laser distribution resulting from the laser-amplification process and often use of frequency up conversion in nonlinear crystals. A inhomogeneous laser distribution on the photocathode produces charged beams with lower beam quality. In this paper, we explore the possible use of microlens arrays (fly-eye light condensers) to dramatically improve the transverse uniformity of the drive laser pulse on UV photocathodes. We also demonstrate the use of such microlens arrays to generate transversely-modulated electron beams and present a possible application to diagnose the properties of a magnetized beam.

Authors:
 [1];  [2];  [3];  [4];  [5];  [4];  [4]
  1. Northern Illinois U.
  2. Tsinghua U., Beijing, Dept. Eng. Phys.
  3. POSTECH
  4. Argonne (main)
  5. NIU, DeKalb
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1402477
Report Number(s):
arXiv:1707.08448; FERMILAB-PUB-17-420-APC
1611710
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: TBD
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS

Citation Formats

Halavanau, A., Qiang, G., Ha, G., Wisniewski, E., Piot, P., Power, J. G., and Gai, W. Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique. United States: N. p., 2017. Web.
Halavanau, A., Qiang, G., Ha, G., Wisniewski, E., Piot, P., Power, J. G., & Gai, W. Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique. United States.
Halavanau, A., Qiang, G., Ha, G., Wisniewski, E., Piot, P., Power, J. G., and Gai, W. 2017. "Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique". United States. doi:. https://www.osti.gov/servlets/purl/1402477.
@article{osti_1402477,
title = {Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique},
author = {Halavanau, A. and Qiang, G. and Ha, G. and Wisniewski, E. and Piot, P. and Power, J. G. and Gai, W.},
abstractNote = {A common issue encountered in photoemission electron sources used in electron accelerators is the transverse inhomogeneity of the laser distribution resulting from the laser-amplification process and often use of frequency up conversion in nonlinear crystals. A inhomogeneous laser distribution on the photocathode produces charged beams with lower beam quality. In this paper, we explore the possible use of microlens arrays (fly-eye light condensers) to dramatically improve the transverse uniformity of the drive laser pulse on UV photocathodes. We also demonstrate the use of such microlens arrays to generate transversely-modulated electron beams and present a possible application to diagnose the properties of a magnetized beam.},
doi = {},
journal = {TBD},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 7
}
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