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20130225 Shift

  • After tuning and startup our shift will begin. Ends Tuesday 9am.

  • Assume 8 hours

1.5hrs

  • load optics (new ones?)
  • background minimisation
  • vary corrector for background and log during - try several correctors (4)
  • vary qm14ff position for background and log during

0.5hrs

  • dispersion measurement
  • multi-otr measurement if working - coupling correction...

1hr

  • lw otr measurement of beam size at lwip
  • lw otr 10 samples for different binnings plus background
  • align for collisions

5hrs

  • optimise
  • correlations x3
  • look at optimal number of points for a scan / different nonlinear scan options
  • long range quad scan

0.5hrs

  • repeat quad scan with otr

21:00 Shift start

  • PLIC shows similar loss in extraction line as last week. Background level
  • Expected as QF21X still at 84A

  • Set file set13feb25_2112.dat
  • Load our optics from set file set13feb22_0718.dat
  • Background around 8000 but charge around 0.9 this week so overall better.
  • Had to flatten orbit a bit, but wasn't too hard.

  • Measuring dispersion - null values - also our scripts won't log
  • magnet mover system had died - several of the ccnets - restart now smile

OTR Measurements

  • OTR focus scan
  • OTR logs of various binnings
  • OTR Quad scan

OTR Quad. Scan

quad_scan.png

Laser-wire Collisions

  • Seed laser refused to lock - tuned, locking now
  • Aligning for collisions 11:45
  • Chamber Horizontal aligned at 461

  • Tuned orbit a bit and checked by varying QM14FF its bba - good!
  • Alignment again
  • H: 420, V:320

Many, many attempts at alignment. Timing was very good, horizontal also and vertical good too. The manipulator cut off the laser within 20um as seen by the APD signal. We tried adding more cable to phase line and retiming at different RF bucket and phase, but still nothing. Just as all was lost, we set it on an uber long vertical scan. When we reached the control room, signal! It was found around V:550. This in conjunction with the fact that we found the best horizontal position around 300um from where we aligned last week suggests the screen is quite misaligned with the laser focus. In this case, the laser is intercepted several hundred microns before the top of the notch were the electron beam is cut off and also the horizontal alignment to the electron beam is off.

Initial Timing

20130226_0047_lws_xy_fit_plot.png

Secondary Phase Alignment - after changing cable length

20130226_0231_lws_xy_fit_plot.png

Collisions found 03:00

Initial Collisions

20130226_0251_lws_xy_errbar_plot1.png

Vertical Alignment Horizontal Alignment
20130226_0134_lws_xy_errbar_plot.png 20130226_0024_lws_xy_errbar_plot.png
Vertical Collisions Horizontal Collisions
20130226_0326_lws_xy_fit_plot.png 20130226_0306_lws_xy_fit_plot2.png

So, vertically, the beam was found at 370, but collisions were actually found at 550. This probably because the screen notch is misaligned to the laser focus. Horizontally, the beam was found at 420, but the peak of collisions were at 200. If the screen is misaligned in both axes (along the laser axis and the electron beam axis), this would correspond to intercepting the edge of the notch at the wrong place. With this information though, collisions should be found more readily even with this alignment.

Laser-wire Scans

  • Nonlinear vertical number 1:
    20130226_0314_lws_xy_fit_plot.png

  • Nonlinear vertical number 2 - just as good!:
    20130226_0327_lws_xy_fit_plot.png

  • Let's find the centre:
    20130226_0259_lws_xy_fit_plot.png

  • Horizontal Scan:
    20130226_0306_lws_xy_fit_plot2.png

  • 60 point nonlinear vertical:
    20130226_0335_lws_xy_fit_plot.png

  • LW Quad Scan :
  • Vertical - 5 samples, 20um range, 10 steps;
  • Horizontal - 20 samples, 3mm range, 30 steps;
  • NL Vertical - 20 samples, 50 steps;

QM14FF Current Vertical Scan Horizontal Scan NL Vertical Scan
81 20130226_0526_lws.dat 20130226_0529_lws.dat 20130226_0536_lws.dat
84 20130226_0552_lws.dat 20130226_0554_lws.dat 20130226_0604_lws.dat
86 20130226_0613_lws.dat 20130226_0615_lws.dat 20130226_0622_lws.dat
89 20130226_0630_lws.dat 20130226_0631_lws.dat 20130226_0639_lws.dat
92 20130226_0650_lws.dat 20130226_0652_lws.dat  
95 20130226_0828_lws.dat 20130226_0830_lws.dat 20130226_0839_lws.dat
98 20130226_0849_lws.dat 20130226_0850_lws.dat 20130226_0858_lws.dat

QM14FF Current Vertical Center Horizontal Center NL Vertical Center
81 537.90 +- 0.91 106.45 +- 5.89 537.98 +- 0.10
84 541.25 +- 0.21 104.05 +- 4.04 540.65 +- 0.07
86 543.58 +- 0.11 96.50 +- 3.57 542.91 +- 0.06
89 546.40 +- 0.14 99.59 +- 3.29 545.39 +- 0.05
92 548.46 +- 0.14 120.54 +- 4.54  
95 550.59 +- 0.04 114.83 +- 4.90 551.42 +- 0.04
98 554.88 +- 0.21 093.65 +- 4.09  

QM14FF Current Vertical Sigma Horizontal Sigma NL Vertical Sigma
81 4.54 +- 0.40 238.75 +- 7.21 4.0 +- 0.14
84 4.85 +- 0.53 232.29 +- 4.74 3.76 +- 0.09
86 3.71 +- 0.17 234.54 +- 4.51 2.23 +- 0.09
89 3.30 +- 0.20 211.95 +- 3.45 1.28 +- 0.11
92 3.25 +- 0.37 233.74 +- 6.15  
95 3.05 +- 0.12 213.30 +- 5.45 0.43 +- 0.12
98 3.27 +- 0.29 190.72 +- 4.31  

QM14FF Current Quick Vertical Horizontal Nonlinear Vertical
81 20130226_0526_lws_xy_fit_plot.png 20130226_0529_lws_xy_fit_plot.png 20130226_0536_lws_xy_fit_plot.png
84 20130226_0552_lws_xy_fit_plot.png 20130226_0554_lws_xy_fit_plot.png 20130226_0604_lws_xy_fit_plot1.png
86 20130226_0613_lws_xy_fit_plot.png 20130226_0615_lws_xy_fit_plot.png 20130226_0622_lws_xy_fit_plot.png
89 20130226_0630_lws_xy_fit_plot.png 20130226_0631_lws_xy_fit_plot.png 20130226_0639_lws_xy_fit_plot.png
92 20130226_0650_lws_xy_fit_plot.png 20130226_0652_lws_xy_fit_plot.png 20130226_0659_lws_xy_fit_plot.png
95 20130226_0828_lws_xy_fit_plot.png 20130226_0830_lws_xy_fit_plot.png 20130226_0839_lws_xy_fit_plot.png
98 20130226_0849_lws_xy_fit_plot.png 20130226_0850_lws_xy_fit_plot.png 20130226_0858_lws_xy_fit_plot1.png

When beam was lost

20130226_0659_lws_xy_scatter_plot.png

07:00 - 'Interesting' Beam

DR Charge dropped off rapidly. Tried to tune linac phases, but with no success. Arakai-san helped. Charge was stored for about 100ms in the DR then decayed. Extraction orbit was stable in the horizontal, but crazy in the vertical. Evenutally seemed to settle, but we were very close to breaking the radiation interlock. 98.7% in the end. Reduced charge to around 0.2 x 10^10 to avoid breaking interlock. Miraculously still had collsions.

  • Scan now demonstrates signal to background of 2:1!! much better than before, in fact the inverse. Two scans at the same place seem to indicate we have a 100nm beam... Whilst wishful, this is doubtful and it is likely a fitting problem due to the specific data. The horizontal size may have changed also - the beam conditions are quite different. However, it seems to make sense to stick to lower charge and to adjust the signal attenuation to scale to the ADC.

  • 08:00 Signal attenuation now 0dB!! Was 9dB before.

1st scan after recovery

20130226_0738_lws_xy_fit_plot1.png

Very small! Better repeat to investigate and verify.

2nd after recovery

20130226_0747_lws_xy_fit_plot.png

  • 3rd after recovery:
    20130226_0758_lws_xy_fit_plot3.png

  • 3rd after recover fitting with just m2 = 1 (errorbars wrong from old software):
    20130226_0758_lws_xy_fit_plot2.png

  • 4th after recover - fewer points:
    20130226_0816_lws_xy_fit_plot.png

  • 5th after recovery - even fewer points:
    20130226_0822_lws_xy_fit_plot.png

Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng 20130226_0024_lws_xy_errbar_plot.png r1 manage 28.1 K 27 Feb 2013 - 07:47 LaurieNevay Horizontal Alignment
PNGpng 20130226_0047_lws_xy_fit_plot.png r1 manage 49.6 K 25 Feb 2013 - 18:34 LaurieNevay Initial Timing
PNGpng 20130226_0134_lws_xy_errbar_plot.png r1 manage 28.2 K 27 Feb 2013 - 07:48 LaurieNevay Vertical Alignment
PNGpng 20130226_0231_lws_xy_fit_plot.png r1 manage 50.0 K 27 Feb 2013 - 07:47 LaurieNevay Secondary Phase Alignment
PNGpng 20130226_0251_lws_xy_errbar_plot1.png r1 manage 37.9 K 25 Feb 2013 - 18:38 LaurieNevay Initial Collisions
PNGpng 20130226_0259_lws_xy_fit_plot.png r1 manage 53.8 K 25 Feb 2013 - 18:40 LaurieNevay Let's find the centre
PNGpng 20130226_0306_lws_xy_fit_plot2.png r1 manage 58.0 K 27 Feb 2013 - 07:46 LaurieNevay Initial Horizontal
PNGpng 20130226_0314_lws_xy_fit_plot.png r1 manage 60.2 K 25 Feb 2013 - 18:39 LaurieNevay Nonlinear vertical number 1
PNGpng 20130226_0326_lws_xy_fit_plot.png r1 manage 55.1 K 27 Feb 2013 - 07:45 LaurieNevay Initial Vertical
PNGpng 20130226_0327_lws_xy_fit_plot.png r1 manage 58.6 K 25 Feb 2013 - 18:40 LaurieNevay Nonlinear vertical number 2 - just as good!
PNGpng 20130226_0335_lws_xy_fit_plot.png r1 manage 61.2 K 25 Feb 2013 - 18:45 LaurieNevay 60 point nonlinear vertical
PNGpng 20130226_0526_lws_xy_fit_plot.png r1 manage 53.2 K 27 Feb 2013 - 09:46 LaurieNevay 0526
PNGpng 20130226_0529_lws_xy_fit_plot.png r1 manage 58.2 K 27 Feb 2013 - 09:51 LaurieNevay 0529
PNGpng 20130226_0536_lws_xy_fit_plot.png r1 manage 59.5 K 27 Feb 2013 - 09:51 LaurieNevay 0536
PNGpng 20130226_0552_lws_xy_fit_plot.png r1 manage 56.7 K 27 Feb 2013 - 09:51 LaurieNevay 0552
PNGpng 20130226_0554_lws_xy_fit_plot.png r1 manage 57.2 K 27 Feb 2013 - 09:52 LaurieNevay 0554
PNGpng 20130226_0604_lws_xy_fit_plot1.png r1 manage 58.6 K 27 Feb 2013 - 09:54 LaurieNevay 0613
PNGpng 20130226_0613_lws_xy_fit_plot.png r1 manage 59.0 K 27 Feb 2013 - 09:55 LaurieNevay 0613
PNGpng 20130226_0615_lws_xy_fit_plot.png r1 manage 54.9 K 27 Feb 2013 - 09:55 LaurieNevay 0615
PNGpng 20130226_0622_lws_xy_fit_plot.png r1 manage 58.5 K 27 Feb 2013 - 09:55 LaurieNevay 0622
PNGpng 20130226_0630_lws_xy_fit_plot.png r1 manage 55.1 K 27 Feb 2013 - 09:56 LaurieNevay 0630
PNGpng 20130226_0631_lws_xy_fit_plot.png r1 manage 55.5 K 27 Feb 2013 - 09:56 LaurieNevay 0631
PNGpng 20130226_0639_lws_xy_fit_plot.png r1 manage 59.1 K 27 Feb 2013 - 09:57 LaurieNevay 0639
PNGpng 20130226_0650_lws_xy_fit_plot.png r1 manage 53.9 K 27 Feb 2013 - 09:57 LaurieNevay 0650
PNGpng 20130226_0652_lws_xy_fit_plot.png r1 manage 55.7 K 27 Feb 2013 - 09:58 LaurieNevay 0652
PNGpng 20130226_0659_lws_xy_fit_plot.png r1 manage 51.7 K 27 Feb 2013 - 10:01 LaurieNevay 0659
PNGpng 20130226_0659_lws_xy_scatter_plot.png r1 manage 36.3 K 27 Feb 2013 - 10:24 LaurieNevay 0659 beam lost
PNGpng 20130226_0738_lws_xy_fit_plot1.png r1 manage 53.3 K 27 Feb 2013 - 10:25 LaurieNevay 1st after recovery
PNGpng 20130226_0747_lws_xy_fit_plot.png r1 manage 55.7 K 27 Feb 2013 - 10:25 LaurieNevay 2nd after recovery
PNGpng 20130226_0758_lws_xy_fit_plot2.png r1 manage 53.6 K 27 Feb 2013 - 10:28 LaurieNevay 3rd after recover fitting with just m2 = 1 (errorbars wrong from old software)
PNGpng 20130226_0758_lws_xy_fit_plot3.png r1 manage 58.2 K 27 Feb 2013 - 10:27 LaurieNevay 3rd after recovery
PDFpdf 20130226_0808_lws_xy_fit_plot.pdf r1 manage 31.2 K 27 Feb 2013 - 10:28 LaurieNevay Horizontal to try and find out why too small
PNGpng 20130226_0816_lws_xy_fit_plot.png r1 manage 56.8 K 27 Feb 2013 - 10:29 LaurieNevay 4th after recover - fewer points
PNGpng 20130226_0822_lws_xy_fit_plot.png r1 manage 56.3 K 27 Feb 2013 - 10:29 LaurieNevay 5th after recovery - even fewer points
PNGpng 20130226_0828_lws_xy_fit_plot.png r1 manage 54.1 K 27 Feb 2013 - 10:12 LaurieNevay 0828
PNGpng 20130226_0830_lws_xy_fit_plot.png r1 manage 54.1 K 27 Feb 2013 - 10:13 LaurieNevay 0830
PNGpng 20130226_0839_lws_xy_fit_plot.png r1 manage 58.4 K 27 Feb 2013 - 10:14 LaurieNevay 0839
PNGpng 20130226_0849_lws_xy_fit_plot.png r1 manage 53.8 K 27 Feb 2013 - 10:14 LaurieNevay 0849
PNGpng 20130226_0850_lws_xy_fit_plot.png r1 manage 56.2 K 27 Feb 2013 - 10:15 LaurieNevay 0850
PNGpng 20130226_0858_lws_xy_fit_plot1.png r1 manage 57.9 K 27 Feb 2013 - 10:22 LaurieNevay 0858
PNGpng quad_scan.png r1 manage 66.6 K 26 Feb 2013 - 09:05 KonstantinKruchinin OTR Quad. Scan
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Topic revision: r11 - 27 Feb 2013 - LaurieNevay

 
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