Accelerator Physics Challenges of X-Ray FEL SASE Sources

Technical Report · Thu May 30 04:00:00 EDT 2002

DOI:https://doi.org/10.2172/799090· OSTI ID:799090

Emma, Paul J ^[1]

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1. SLAC

A great deal of international interest has recently focused on the design and construction of free-electron lasers (FEL) operating in the x-ray region ({approx}1 {angstrom}). At present, a linac-based machine utilizing the principle of self-amplified spontaneous emission (SASE) appears to be the most promising approach. This new class of FEL achieves lasing in a single pass of a high brightness electron beam through a long undulator. The requirements on electron beam quality become more demanding as the FEL radiation wavelength decreases, with the 1-{angstrom} goal still 3-orders of magnitude below the shortest wavelength operational SASE FEL (TTF-FEL at DESY [1]). The subpicosecond bunch length drives damaging effects such as coherent synchrotron radiation, and undulator vacuum chamber wakefields. Unlike linear colliders, beam brightness needs to be maintained only over a small ''slice'' of the bunch length, so the concepts of bunch integrated emittance and energy spread are less relevant than their high-frequency (or ''time-sliced'') counterparts, also adding a challenge to phase space diagnostics. Some of the challenges associated with the generation, preservation, measurement, and stability of high brightness FEL electron beams are discussed here.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (US)
• Sponsoring Organization: USDOE Office of Energy Research (ER) (US)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 799090
• Report Number(s): SLAC-PUB-9243
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
ELECTRON BEAMS
LINEAR COLLIDERS
PHASE SPACE
PHYSICS
RADIATIONS
SYNCHROTRON RADIATION
WAVELENGTHS
WIGGLER MAGNETS