CLS: Combined Laser System for the NLC
The CLS uses a mode locked Ti:Sapphire oscillator, and multi-pass amplifier, pumped by a long pulse YAG laser to produce a pulse train with flexible timing. This laser system is appropriate for the following systems:
1. NLC source laser - This laser will be used to generate polarized electrons for the NLC.
2. LCLS source laser - Source laser for the RF photocathode gun for the LCLS.
3. NLC laser wire - Some or all of the NLC laser wires will use a femptosecond laser to allow temporal profile measurements.
| Parameter (approximate) | NLC source | LCLS source | NLC Laser Wire |
| Repetition rate | 120Hz | 120Hz | 120Hz |
| Wavelength T = tunability, R = allowable range | 800-880nm T | 260-280nm R | <1000nm R |
| Number of pulses | 100 - 200 | 1 | 100-200 |
| Pulse length (FWHM) | 200-500psec | 10psec | 1psec (50fsec)* |
| Pulse rise and fall time | <100psec | <1psec | ~Gaussian |
| Pulse energy (to target) | 30uJ | 500uJ | >10uJ |
| Pulse train energy before doubling or compression | 6mJ | 18mJ | >8mJ |
| Pulse energy stability | <0.5% RMS | <0.5% RMS | <5% RMS |
* 50 fsec is for measuring the temporal shape of the electron pulse.
Motivation for combining the laser systems:
The independently designed optimal laser systems for each of these applications are quite similar. All would use chirp pulse amplified Ti:Sapphire systems (without re-compression for the NLC source). Using identical components will substantially reduce the development costs and allow for simpler maintenance of the systems.
These laser systems all use variants of Chirp Pulse Amplification
Due to the short pulse lengths required, it is clear that the LCLS source and Laser Wire should use some type of CPA technique. Although there are several options for generating the longer pulse length of the NLC source laser, it appears that a chip pulse amplifier without pulse re-compression is the most practical.
System Components and estimated costs:
System Costing as of April 2000: NLCLaserCostsApril2000.xls (corrected 4/18/200)
Old Documents
NLCLaserCosting.pdf NLCLaserCosting.xls
LaserCD1talk.ppt LaserCD1talk.pdf
Page by Josef Frisch frisch@slac.stanford.edu 04/22/2002
Links to: the NLC Home Page, the SLAC and KEK Institutional Home Pages.
Page by: Josef Frisch