Scaling relations and parameters for 1 Angstrom FEL. [Free Electron Laser]

Conference · Mon Jan 01 00:00:00 EST 1990

OSTI ID:6112115

Yu, L H

The Free Electron Laser (FEL) holds great promise as a tunable source of coherent radiation. At the present, the shortest wavelength achieved by an FEL is 2500 {Angstrom}. However, as recent progress in the development of laser driven photocathode electron guns has provided electron beams with lower and lower emittance and higher and higher current, it has become clear that FEL's with much shorter wavelength can be achieved. An FEL operating below 1000 {Angstrom} will yield important advances in fields such as photochemistry, atomic and molecular physics. An FEL with wavelength of 30 {Angstrom} will bring new era to the development of holography of living cells. And, if an FEL with 1 {Angstrom} wavelength can be developed, its impact on solid physics, molecular biology, and many other fields can hardly be exaggerated. We first describe our electron distribution model: a waterbag transverse phase space distribution and a Gaussian energy distribution. This model is widely used in simulations, and is rather close to reality. Then we describe the dispersion relation derived from the Vlasov-Maxwell equations, and its solution, expressed in scaled form. We compare the variational approximation with several simulation codes. Then we compare with exact results which we have derived for a parallel electron beam with finite beam size and energy spread. We explain the scaling relations, and give examples to show how system parameters scale when the FEL wavelength is reduced. Then, applying these scaling relations, we derive a list of preliminary system parameters for a 1 {Angstrom} FEL. As an example, we apply our analytical calculation to optimize one set of parameters derived from the scaling relations. Finally, as a conclusion we discuss the implication of the list of parameters for a 1{Angstrom} FEL. 20 refs., 4 figs.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (USA)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6112115
• Report Number(s): BNL-45824; CONF-9004232-6; ON: DE91009441; TRN: 91-009505
• Resource Relation: Conference: Prospects for a 1 Angstrom Free-Electron Laser (FEL) workshop, Sag Harbor, NY (USA), 22-27 Apr 1990
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
FREE ELECTRON LASERS
GAIN
SCALING LAWS
ANALYTICAL SOLUTION
BEAM EMITTANCE
COHERENT RADIATION
COMPUTERIZED SIMULATION
ELECTRON BEAMS
EXTREME ULTRAVIOLET RADIATION
FOCUSING
GAUSS FUNCTION
OPTICAL DISPERSION
OPTIMIZATION
SPECIFICATIONS
WIGGLER MAGNETS
AMPLIFICATION
BEAMS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELECTROMAGNETS
EQUIPMENT
FUNCTIONS
LASERS
LEPTON BEAMS
MAGNETS
PARTICLE BEAMS
RADIATIONS
SIMULATION
ULTRAVIOLET RADIATION
426002* - Engineering- Lasers & Masers- (1990-)
990200 - Mathematics & Computers