| Autor: |
Corlett, J.N., Barletta, W.A., DeSantis, S., Doolittle, L., Fawley, W.M., Heimann, P., Leone, S., Lidia, S., Li, D., Penn, G., Ratti, A., Reinsch, M., Schoenlein, R., Staples, J., Stover, G., Virostek, S., Wan, W., Wells, R., Wilcox, R., Wolski, A., Wurtele, J., Zholents, A. |
| Jazyk: |
angličtina |
| Rok vydání: |
2004 |
| Předmět: |
|
| Zdroj: |
Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Heimann, P.; et al.(2004). LUX-a recirculating linac-based facility for ultrafast X-ray science. Lawrence Berkeley National Laboratory. Lawrence Berkeley National Laboratory: Lawrence Berkeley National Laboratory. Retrieved from: http://www.escholarship.org/uc/item/77b8z601 |
| Popis: |
We present recent developments in design concepts for LUX - a source of ultra-short synchrotron radiation pulses based on a recirculating superconducting linac. The source produces high-flux x-ray pulses with duration of 100 fs or less at a 10 kHz repetition rate, optimized for the study of ultra-fast dynamics across many fields of science [1]. Cascaded harmonic generation in free-electron lasers (FEL's) produces coherent radiation in the VUV-soft x-ray regime, and a specialized technique is used to compress spontaneous emission for ultra-short-pulse photon production in the 1-10 keV range. High-brightness electron bunches of 2-3 mm-mrad emittance at 1 nC charge in 30 ps duration are produced in an rf photocathode gun and compressed to 3 ps duration following an injector linac, and recirculated three times through a 1 GeV main linac. In each return path, independently tunable harmonic cascades are inserted to produce seeded FEL radiation in selected photon energy ranges from approximately 20 eV with a single stage of harmonic generation, to 1 keV with a four-stage cascade. The lattice is designed to minimize emittance growth from effects such as coherent synchrotron radiation (CSR), and resistive wall wakefields. Timing jitter between pump lasers and x-ray pulses is minimized by use of a stable optical master oscillator, distributing timing signals over actively stabilized fiber-optic, phase-locking all lasers to the master oscillator, and generating all rf signals from the master oscillator. We describe technical developments including techniques for minimizing power dissipation in a high repetition rate rf photocathode gun, beam dynamics in two injector configurations, independently tunable beamlines for VUV and soft x-ray production by cascaded harmonic generation, a fast kicker design, timing systems for providing synchronization between experimental pump lasers and the x-ray pulse, and beamline design for maintaining nm-scale density modulation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
