• Open Access

Multiobjective optimizations of a novel cryocooled dc gun based ultrafast electron diffraction beam line

Colwyn Gulliford, Adam Bartnik, and Ivan Bazarov
Phys. Rev. Accel. Beams 19, 093402 – Published 23 September 2016

Abstract

We present the results of multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line utilizing a 225 kV dc gun with a novel cryocooled photocathode system and buncher cavity. Optimizations of the transverse projected emittance as a function of bunch charge are presented and discussed in terms of the scaling laws derived in the charge saturation limit. Additionally, optimization of the transverse coherence length as a function of final rms bunch length at the sample location have been performed for three different sample radii: 50, 100, and 200μm, for two final bunch charges: 105 electrons (16 fC) and 106 electrons (160 fC). Example optimal solutions are analyzed, and the effects of disordered induced heating estimated. In particular, a relative coherence length of Lc,x/σx=0.27nm/μm was obtained for a final bunch charge of 105 electrons and final bunch length of σt100fs. For a final charge of 106 electrons the cryogun produces Lc,x/σx0.1  nm/μm for σt100200fs and σx50μm. These results demonstrate the viability of using genetic algorithms in the design and operation of ultrafast electron diffraction beam lines.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
1 More
  • Received 18 April 2016

DOI:https://doi.org/10.1103/PhysRevAccelBeams.19.093402

This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Published by the American Physical Society

Physics Subject Headings (PhySH)

  1. Research Areas
Accelerators & Beams

Authors & Affiliations

Colwyn Gulliford*, Adam Bartnik, and Ivan Bazarov

  • CLASSE, Cornell University, 161 Synchrotron Drive, Ithaca, New York 14853-8001, USA

  • *cg248@cornell.edu

Article Text

Click to Expand

References

Click to Expand
Issue

Vol. 19, Iss. 9 — September 2016

Reuse & Permissions
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Accelerators and Beams

Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 3.0 License. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

×

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×