Setup in/out

New values (2023 Nov 22)

Most recent reference motor positions: Reference Motor Positions

Old values/procedure

Taken from: https://docs.google.com/document/d/1tPpJLqZOzpGEWFv78RUuRDg0SSzgegZMacqA98gymrA/edit?usp=sharing


Collision parameters

  • e-beam: 30 micron (sigma of Gaussian distribution)
  • laser: 70 fs FWHM (maybe down to 50 fs)

General notes:

  • For all scans: add all scalar lists to the dataset

Initial e-beam parameters

  • waist at PIC_CENT
  • beta function: 0.5m

General preparation

Recover Laser on MO_MAG

  • Align laser to tunnel
  • Move RP attenuator out, ND filters in (ND2 for alignment, ND6 when sending laser into OAP)
  • Recover M1/M2 alignment using FrontView
  • Verify that laser is back on MO
  • First focal scan to verify laser quality

Recover EOS

  • Prepare EOS: first polarizer: full transmission; camera/analyzing polarizer: maximum extinction
  • EOS timing scan to find t0 for EOS:

Spatial Alignment: KES

  • Align vertical: 1 micron steps, over 100 micron, 10 per step (1000 shots ~< 2 minutes); record both MO_MAG and GAMMA1

  • Align horizontal:

Timing YAG

  • Find t0 using a) long-range scan b) fine scan (10fs-steps)
  • Move EOS delay stage to see EOS and YAG timing simultaneously
  • long scan (YAG + EOS): 5ps window around t0, 10fs steps, 5 per step (2500 shots ~< 5 minutes); MO_MAG + EOS
  • fine scan (YAG + EOS): 100fs window around t0, 1fs steps, 25 per step (2500 shots ~< 5 minutes); MO_MAG + EOS
  • jitter scan (YAG + EOS): keep timing at t0, take 2500 shots at the same position; MO_MAG + EOS

Collisions

  • Remove MO tower and YAG from the IP
  • Remove ND filters / attenuator
  • Remove glass window between compressor and picnicbasket?!
  • Compensate timing for the change in effective path length
  • long timing scan 10ps window around t0, 10fs steps, 5 per step (5000 shots ~< 10 minutes); GAMMA1 + LFOV + COMP_NEAR + PB_NEAR
    find new t0
  • 2D horizontal vs. time scan 100fs window around t0, 3fs steps (i.e., 30 settings) vs. 100 micron around maximum overlap, 3 micron steps (i.e., 30 settings), 5 shots per setting: 4500 shots (~< 10 minutes)
    find new t0 vs. horizontal0 (position/time of best overlap / strongest non-linear signal)
  • 1D vertical scan (scan ~100 micron in 0.1 micron steps, 5 shots per step → 5000 shots (~< 10 minutes)
    find best vertical position
    change spectrometer setting such that the nonlinear signal can be seen clearly
  • repeat 2D horizontal vs. time scan with LFOV_LBG

Electron-spectrometer calibration

  • Do a calibration scan whenever something is changed (either beam properties or magnet settings)







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