Development of a pump-probe facility with sub-picosecond time resolution combining a high-power ultraviolet regenerative FEL amplifier and a soft X-ray SASE FEL

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 475; no. 1; pp. 368 - 372
• Main Authors: Faatz, B, Fateev, A.A, Feldhaus, J, Krzywinski, J, Pflueger, J, Rossbach, J, Saldin, E.L, Schneidmiller, E.A, Yurkov, M.V
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 21.12.2001
• Subjects: Free electron laser; High-gain FEL; Ultraviolet source; 52.75.M; 42.72.Bj; Free electron laser; 41.60.Cr; Ultraviolet source; High-gain FEL
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(01)01541-8

This paper presents the conceptual design of a high power radiation source with laser-like characteristics in the ultraviolet spectral range at the TESLA Test Facility (TTF). The concept is based on the generation of radiation in a regenerative FEL amplifier (RAFEL). The RAFEL described in this paper covers a wavelength range of 200–400 nm and provides 200 fs pulses with 2 mJ of optical energy per pulse. The linac operates at 1% duty factor and the average output radiation power exceeds 100 W. The RAFEL will be driven by the spent electron beam leaving the soft X-ray FEL, thus providing minimal interference between these two devices. The RAFEL output radiation has the same time structure as the X-ray FEL and the UV pulses are naturally synchronized with the soft X-ray pulses from the TTF FEL. Therefore, it should be possible to achieve synchronization close to the duration of the radiation pulses (200 fs) for pump-probe techniques using either an UV pulse as a pump and soft X-ray pulse as a probe, or vice versa.