06 Beam Instrumentation and Feedback
T25 Lasers
Paper Title Page
MOPO042 Photonic Crystal Fibre Laser for Electron Beam Emittance Measurement* 577
 
  • L. Corner, L.J. Nevay, R. Walczak
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
 
  We discuss the recent progress in the development of a high repetition rate, high energy fibre laser for intratrain laser-wire scans of transverse electron beam sizes. A commercial fibre laser (1uJ, 6.49MHz) is amplified in rod type photonic crystal fibre using a burst mode format, which has the advantage of allowing us to exploit very high transient gain while reducing the heat load deposited in the amplifier. The amplified pulses are over 180uJ spaced at 154ns, suitable for intratrain scanning at the ATF2. The spatial beam quality is excellent (M2 = 1.07), indicating that it will be possible to focus the laser to a spot size of ~ λ, enabling us to reach high intensities. The amplified pulse duration is 200ps, which can be compressed to less than the electron bunch length to increase the laser-wire signal to noise ratio. The performance of the laser system is analysed with respect to the demands of the laser-wire experiment.  
 
MOPO043 Applications of Lasers to Accelerator Physics at SSRL 580
 
  • D.L. Robinson
    Cal Poly, San Luis Obispo, California, USA
  • W.J. Corbett
    SLAC, Menlo Park, California, USA
 
  Recent advances in accelerator physics and SR research have generated the need for high-power lasers in the SPEAR3 accelerator complex. On the injector side, two lasers are being used to test different photocathode materials and to provide photo-assisted emission from the standard dispenser cathode RF gun. For the storage ring, both a TiSa oscillator and a fiber laser locked to the RF master oscillator have been used to characterize short-pulse electron bunches in cross-correlation experiments. These lasers are also used in SR experiments for pump-probe characterization of materials. In this paper we review the laser-based systems, preliminary results and outlook for the future.  
 
MOPO044 Bunch Length Measurements in Low-Alpha Mode at SPEAR3 with First Time-Resolved Pump/Probe Experiments* 583
 
  • J.S. Wittenberg, A. Lindenberg, A. Miller
    Stanford University, Stanford, California, USA
  • W.J. Corbett, L. Wang
    SLAC, Menlo Park, California, USA
 
  Funding: Work sponsored by U.S. Department of Energy Contract DE-AC03-76SF00515, Office of Basic Energy Sciences and SLAC Laboratory Directed Research Development funds (LDRD)
The SPEAR3 synchrotron light source can be operated in low-alpha mode to generate x-ray pulse durations of order 1ps, well below streak camera resolution limits yet accessible by laser/sr cross-correlation measurements. Initial CC tests performed with a 50fs TiSa laser, frequency doubling BBO, photodiode and lock-in amplifier resolved bunch lengths down to about 6ps rms with 85uA single-bunch current. By reconfiguring the experimental setup to utilize a fiber laser, sum frequency generation and single photon counter it is now possible to measure profiles in the 1ps rms range with only 5uA single-bunch current. In this paper we report on the most recent measurements, simulations, modeling efforts and prospects for further improvement.