Coherence Properties of the LCLS Metadata

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Title

  • Main Title Coherence Properties of the LCLS

Creator

  • Author: Ocko, Samuel
    Creator Type: Personal

Contributor

  • Sponsor: United States. Department of Energy. Office of Science.
    Contributor Type: Organization
    Contributor Info: US DOE Office of Science (DOE SC)

Publisher

  • Name: SLAC National Accelerator Laboratory
    Place of Publication: [California]

Date

  • Creation: 2010-08-25

Language

  • English

Description

  • Content Description: The LINAC Coherent Light Source (LCLS), an X-Ray free-electron laser(FEL) based on the self amplified spontaneous emission principle, has recently come on-line. For many users it is desirable to have an idea of the level of transverse coherence of the X-Ray beam produced. In this paper, we analyze the output of GENESIS simulations of electrons traveling through the FEL. We first test the validity of an approach that ignores the details of how the beam was produced, and instead, by assuming a Gaussian-Schell model of transverse coherence, predicts the level of transverse coherence simply through looking at the beam radius at several longitudinal slices. We then develop a Markov chain Monte Carlo approach to calculating the degree of transverse coherence, which offers a {approx}100-fold speedup compared to the brute-force algorithm previously in use. We find the beam highly coherent. Using a similar Markov chain Monte Carlo approach, we estimate the reasonability of assuming the beam to have a Gaussian-Schell model of transverse coherence, with inconclusive results.
  • Physical Description: 20 pages

Subject

  • Keyword: Coherence
  • University of North Texas Libraries Browse Structure: Science and Technology

Collection

  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI

Institution

  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Report

Format

  • Text

Identifier

  • Report No.: SLAC-TN-10-013
  • Grant Number: AC02-76SF00515
  • DOI: 10.2172/992935
  • Office of Scientific & Technical Information Report Number: 992935
  • Archival Resource Key: ark:/67531/metadc1012148

Note

  • Display Note: http://www-public.slac.stanford.edu/SciDoc/docMeta.aspx?slacPubNumber=slac-tn-10-013
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