Design of an x-ray free electron laser undulator
Abstract
An undulator designed to be used for an x-ray free electron laser has to meet a set of stringent requirements. With no optical cavity, an x-ray FeL operates in the single pass Self Amplified Spontaneous Emission (SASE) mode; an electron macropulse is microbunched by an undulator and the radiation it creates. The microbunched pulse emits spontaneous radiation and coherent FEL radiation, whose power may reach saturation in a sufficiently long and perfect undulator. The pulse must have low emittance and high current, and its trajectory in the undulator must keep the radiation and the pulse together with a very high degree of overlap. The authors shall consider the case of the Linear Coherent Light Source (LCLS) FEL project at SLAC, which is intended to create 1.5 {angstrom} x-rays using an electron beam with 15 GeV energy, 1.5{pi} mm-mrad normalized emittance, 3,400 A peak current, and 280 fsec FWHM bunch duration. They find that this 65 {micro}m rms diameter beam must overlap its radiation with a walk/off of no more than 5 {micro}m for efficient gain. This places severe limitations on the magnetic field errors and other mechanical tolerances. The following is a discussion of the undulator design, specifications, alignment, engineering,more »
- Authors:
- Publication Date:
- Research Org.:
- Stanford Univ., Stanford Linear Accelerator Center, CA (US)
- Sponsoring Org.:
- USDOE Office of Energy Research, Washington, DC (US)
- OSTI Identifier:
- 663315
- Report Number(s):
- SLAC-PUB-7651; CONF-9706157-
Journal ID: ISSN 0094-243X; ON: DE98059141; TRN: US200305%%912
- DOE Contract Number:
- AC03-76SF00515
- Resource Type:
- Conference
- Resource Relation:
- Conference: SRI '97: 10. U.S. national conference on synchrotron radiation instrumentation, Ithaca, NY (US), 06/17/1997--06/20/1997; Other Information: Supercedes report DE98059141; PBD: Sep 1997; PBD: 1 Sep 1997
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 43 PARTICLE ACCELERATORS; 42 ENGINEERING; ALIGNMENT; BEAM POSITION; ELECTRON BEAMS; ELECTRONS; FREE ELECTRON LASERS; LIGHT SOURCES; MAGNETIC FIELDS; MONITORING; RADIATIONS; SATURATION; SPECIFICATIONS; STANFORD LINEAR ACCELERATOR CENTER; SYNCHROTRON RADIATION; WIGGLER MAGNETS
Citation Formats
Carr, R. Design of an x-ray free electron laser undulator. United States: N. p., 1997.
Web. doi:10.1063/1.54589.
Carr, R. Design of an x-ray free electron laser undulator. United States. https://doi.org/10.1063/1.54589
Carr, R. 1997.
"Design of an x-ray free electron laser undulator". United States. https://doi.org/10.1063/1.54589. https://www.osti.gov/servlets/purl/663315.
@article{osti_663315,
title = {Design of an x-ray free electron laser undulator},
author = {Carr, R},
abstractNote = {An undulator designed to be used for an x-ray free electron laser has to meet a set of stringent requirements. With no optical cavity, an x-ray FeL operates in the single pass Self Amplified Spontaneous Emission (SASE) mode; an electron macropulse is microbunched by an undulator and the radiation it creates. The microbunched pulse emits spontaneous radiation and coherent FEL radiation, whose power may reach saturation in a sufficiently long and perfect undulator. The pulse must have low emittance and high current, and its trajectory in the undulator must keep the radiation and the pulse together with a very high degree of overlap. The authors shall consider the case of the Linear Coherent Light Source (LCLS) FEL project at SLAC, which is intended to create 1.5 {angstrom} x-rays using an electron beam with 15 GeV energy, 1.5{pi} mm-mrad normalized emittance, 3,400 A peak current, and 280 fsec FWHM bunch duration. They find that this 65 {micro}m rms diameter beam must overlap its radiation with a walk/off of no more than 5 {micro}m for efficient gain. This places severe limitations on the magnetic field errors and other mechanical tolerances. The following is a discussion of the undulator design, specifications, alignment, engineering, and beam position monitoring they plan to implement for the LCLS X-ray FEL.},
doi = {10.1063/1.54589},
url = {https://www.osti.gov/biblio/663315},
journal = {},
issn = {0094-243X},
number = ,
volume = ,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 1997},
month = {Mon Sep 01 00:00:00 EDT 1997}
}