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20130221 Shift

  • NOTE for this shift - the new laser-wire plic monitor will be in the data as tekm1 and tekm2. m1 is the peak voltage from the pmt - negative. m2 is the width of the signal - approximately 150ns. Didn't get time to set up a gate or an adc so this will have to do. For the timing overlap scans of phase the scope settings were changed and so m1 and m2 in these files are the peak and width of the apd signal. The scope was set back for the plic.

  • Start 20:00

  • Set file set13feb21_2003
  • Detector saturated with settings from last week, but orbit incredibly flat.
  • Likely due to the resteering through the machine with B3X earlier in the week being vertically rolled.
  • 100 pulse log with machine as is 20130221_2004_log.dat

  • QF21X was changed to 84.468A on 20th Feb day shift. Last week value was 65.929A. Setting to 65 unsaturates background. Must be due to beta function change.

  • Access at 21:00 to align laser. Laser aligned ok and approximately 100mJ measured downstairs. No damage, everything looks fine. Energy meter fixed.

  • Beam resumed 22:05
  • Tuning linac phases individually in turn to maximise energy. Compensate with modulator #8 to achieve correct energy in the end.

  • 100 pulse log with measured orbit 20130222_0231_log.dat
  • Emittanace measurement, dispersion measurement done using FS tools. Also, measured tune using damping ring exciter and put in FS.
  • Reoptimise orbit near LWIP as angle around -200urad vertically and -100urad horizontally. Usually go for less than 100urad in both.

Dispersion at OTRs

20130222_0030_dispersion_at_otrs.png

Dispersion Measurement

20130222_0215_dispersion_measurement.png

OTR Emittance Measurement

20130222_0210_otr_emittance.png

Flight Simulator Twiss Parameters for Final Focus 20130222_0230_ff_twiss.png

Flight Simulator Twiss Parameters for Final Focus and Extraction Line

20130222_0230_twiss2.png

Horizontal Alignment

20130222_0310_lws_xy_errbar_plot.png

Phase Timing 1 Phase Timing 2
20130222_0338_lws_xy_errbar_plot1.png 20130222_0440_lws_xy_fit_plot.png

Vertical Alignment Horiontal Alignment
20130222_0444_lws_xy_errbar_plot.png 20130222_0516_lws_xy_errbar_plot.png

Phase Laserwire Scan

20130222_0522_lws_xy_fit_plot.png

Non Linear Scan 1

20130222_0526_lws_xy_fit_plot1.png

  • Repeated Nonlinear Scan:
    20130222_0543_lws_xy_fit_plot.png

  • Laser and Charge Normalised:
    20130222_0543_lws_xy_fit_plot1.png

  • Fitting again:
    20130222_0543_lws_xy_fit_plot3.png

  • Sigma Comparison:
    20130222_0543_sigma_comparison.png

  • Suspiciously Small...:
    20130222_0559_lws_xy_fit_plot.png

So scans are returning very small values and also these values vary from fit to fit. There are a few points to address here:

  • There are too many points on peak that could be weighting the fitting badly - should really program negative log likelihood instead of reduced chi2
  • The points on peak are all very close together - the nonlinear scan points method really isn't perfect.
  • +- 200um range is unnecessarily large and hides the interesting bits on peak in the plots

  • Adjusted nonlinear scan points to have minimum step size of 0.35um vs 0.2um before.
  • reduced number of points in scan to 50 and then to 40.
  • increased number of samples to 20 then to 30 at each point to reduced error bars through statistics
  • Reduced overall range of nonlinear scan to 150um total

So last of the nonlinear scans in the same place for now. Seems to be good with 40 - 50 samples points with new settings - 0.35um minimum step size, 150um range.

  • Horizontal Scan for accurate horizontal size -> need for vertical fitting

  • Set file: set13feb22_0718.dat
  • Damping ring tune: H: 0.1718 V: 0.5644

  • Charge ramp - 1000 pulse log 20130222_0731_log.dat
  • Laser energy ramp - 1000 pulse log 20130222_0739_log.dat

Energy meter insists on producing serial port error, but then continues to receive data when you click ok - a totally pointless message. Contaminated last laser energy scan.

  • 500 pulse laser energy on collision log - 20130222_0745_log.dat
  • Background charge ramp - 1000 pulse log 20130222_0749_log.dat - no laser

  • optimise green output at full power - green not too bad.
  • go from 100us delay to 90us delay to increase signal to noise
  • Energy meter reads about 103mJ.

4 vertical scans for different charge settings

  • Fitted with sigma ex = 204.4um, m2=1 fits used as a physical upper limit on the size.
  • 30 pulses, centre 756.7, 40 steps.

Gun Intensity Mean Charge (by eye) Filename $\sigma_{ey}$ Empirical $\sigma_{ey}$ M$^2$ = 1
15% 0.6 20130222_0807_lws.dat 0.51 +- 0.23 0.95 +- 0.15
11% 0.5 20130222_0818_lws.dat 0.60 +- 0.16 1.03 +- 0.11
8% 0.4 20130222_0828_lws.dat 0.75 +- 0.17 1.13 +- 0.14
6% 0.3 20130222_0838_lws.dat 0.10 +- 0.21 0.60 +- 0.17
4% 0.15 20130222_0848_lws.dat 1.54 +- 0.16 1.86 +- 0.15

4 vertical scans for different laser settings

  • Increase number of points this time
  • Gun laser intensity back to 15%
  • 30 pulses, center 756.7, 50 steps
  • Fitted with sigma ex = 204.4um, m2=1 fits used as a physical upper limit on the size.

Flash Lamp Delay Mean Energy Filename $\sigma_{ey}$ Empirical $\sigma_{ey}$ M$^2$ = 1 Amplitude (charge normalised)
70us 103mJ 20130222_0901_lws.dat 0.57 +- 0.10 0.97 +- 0.07 2.17 +- 0.02
100us 87mJ 20130222_0927_lws.dat 1.14 +- 0.14 1.46 +- 0.09 1.98 +- 0.03
130us   20130222_0942_lws.dat 0.66 +- 0.14 1.05 +- 0.10 1.92 +- 0.03
160us   20130222_0957_lws.dat 1.00 +- 0.23 1.48 +- 0.21 1.38 +- 0.04
190us 16mJ 20130222_1008_lws.dat 0.10 +- 0.24 0.10 +- 0.36 0.85 +- 0.03

  • Back to 70us flash lamp delay.
  • High resolution vertical scan
  • Long range horizontal scan

  • Switch to OTR to measure same beam size.

  • Resume Laserwire - straight back on collisions

  • Quad scan +- 15 amps in 3 amp steps about centre
  • Centre -90A

  • Vertical: 5 pulses, 30um range, 10 steps
  • Horizontal: 20 pulses, 2mm range, 40 steps
  • Nonlinear scan: 30 pulses, 150mm range, 50 steps

QM14FF Current Vertical Horizontal Non-linear Vertical
77 20130222_1204_lws.dat 20130222_1206_lws.dat 20130222_1218_lws.dat
80 20130222_1234_lws.dat 20130222_1236_lws.dat 20130222_1246_lws.dat
83 20130222_1257_lws.dat 20130222_1300_lws.dat 20130222_1309_lws.dat
84 20130222_1320_lws.dat 20130222_1323_lws.dat 20130222_1332_lws.dat
87 20130222_1241_lws.dat 20130222_1344_lws.dat 20130222_1357_lws.dat
90 20130222_1408_lws.dat 20130222_1410_lws.dat 20130222_1424_lws.dat
93 20130222_1436_lws.dat 20130222_1429_lws.dat 20130222_1453_lws.dat
96 20130222_1632_lws.dat 20130222_1634_lws.dat 20130222_1647_lws.dat
99 20130222_1657_lws.dat 20130222_1701_lws.dat 20130222_1714_lws.dat
102 20130222_1723_lws.dat 20130222_1725_lws.dat 20130222_1740_lws.dat

QM14FF Current Vertical Centre Horizontal Centre Vertical Centre
77 749.7 +- 0.2 63.3 +- 11.3 752.8 +- 0.2
80 753.9 +- 0.2 57.8 +- 3.1 753.8 +- 0.1
83 754.8 +- 0.3 46.8 +- 2.9 754.6 +- 0.1
84 753.9 +- 0.3 50.8 +- 5.3 755.0 +- 0.1
87 754.6 +- 0.3 72.7 +- 2.6 755.8 +- 0.1
90 754.9 +- 0.3 59.2 +- 6.1 755.8 +- 0.1
93 755.6 +- 0.5 55.7 +- 6.9 750.44 +- 2.21
96 750.55 +- 0.31 82.9 +- 3.51 750.07 +-0.08
99 751.24 +- 0.53 65.25 +- 21.12 748.27 +- 0.09
102 748.18 +- 0.64 -18.33 +- 9.22 747.07+-0.19

QM14FF Current Vertical Sigma Horizontal Sigma Vertical Sigma
77 4.04 +- 0.72 257.3 +- 14.9 3.02 +- 0.21
80 4.71 +- 0.21 228.9 +- 3.9 3.67 +- 0.16
83 5.38 +- 0.34 216.2 +- 3.5 2.77 +- 0.44
84 2.37 +- 0.34 219.1 +- 6.8 2.61 +- 0.13
87 4.30 +- 0.54 201.5 +- 3.0 2.30 +- 0.15
90 3.97 +- 0.50 204.4 +- 8.1 0.73 +- 0.27
93 3.36 +- 0.85 185.2 +- 8.4 3.27 +- 2.02
96 2.80 +- 0.56 175.84 +- 4.51 1.87 +- 0.14
99 5.46 +- 2.00 291.96 +- 23.18 1.64 +- 0.13
102 3.82 +- 0.92 207.72 +- 14.59 2.30 +- 0.30

  • Initial Fit Plot Looks good...:
    20130222_0640_lws_xy_fit_plot1.png

  • Sigma Comparison:
    _sigma_comparison1.png

  • comparison zoom:
    _sigma_comparison1_zoom2.png

  • Horizontal Scan:
    20130222_0716_lws_xy_fit_plot.png

  • 20130222_0818_lws_xy_fit_plot.png:
    20130222_0818_lws_xy_fit_plot.png

  • 20130222_0828_lws_xy_fit_plot.png:
    20130222_0828_lws_xy_fit_plot.png

  • perhaps a little small:
    20130222_0838_lws_xy_fit_plot.png291.96 +-
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng 20130222_0030_dispersion_at_otrs.png r1 manage 12.9 K 21 Feb 2013 - 17:35 LaurieNevay 20130222_0030_dispersion_at_otrs.png
PNGpng 20130222_0210_otr_emittance.png r1 manage 76.3 K 21 Feb 2013 - 17:54 LaurieNevay b
PNGpng 20130222_0215_dispersion_measurement.png r1 manage 79.9 K 21 Feb 2013 - 17:53 LaurieNevay a
PNGpng 20130222_0230_ff_twiss.png r1 manage 26.0 K 21 Feb 2013 - 17:54 LaurieNevay c
PNGpng 20130222_0230_twiss2.png r1 manage 28.3 K 21 Feb 2013 - 17:55 LaurieNevay d
PNGpng 20130222_0255_magmovers.png r1 manage 60.5 K 21 Feb 2013 - 17:56 LaurieNevay e
PNGpng 20130222_0310_lws_xy_errbar_plot.png r1 manage 26.6 K 21 Feb 2013 - 20:48 LaurieNevay Horizontal Alignment
PDFpdf 20130222_0338_lws_xy_errbar_plot1.pdf r1 manage 20.0 K 21 Feb 2013 - 20:49 LaurieNevay PhaseTiming1
PNGpng 20130222_0338_lws_xy_errbar_plot1.png r1 manage 27.2 K 21 Feb 2013 - 21:26 LaurieNevay PhaseTiming1
PDFpdf 20130222_0343_lws_xy_fit_plot.pdf r1 manage 26.5 K 21 Feb 2013 - 20:50 LaurieNevay PhaseTiming2
PDFpdf 20130222_0353_lws_xy_errbar_plot.pdf r1 manage 24.1 K 21 Feb 2013 - 20:51 LaurieNevay Initial Collisions
PDFpdf 20130222_0440_lws_xy_fit_plot.pdf r1 manage 25.7 K 21 Feb 2013 - 20:51 LaurieNevay PhaseTiming3
PNGpng 20130222_0440_lws_xy_fit_plot.png r1 manage 51.4 K 21 Feb 2013 - 21:26 LaurieNevay PhaseTiming2
PNGpng 20130222_0444_lws_xy_errbar_plot.png r1 manage 28.4 K 21 Feb 2013 - 20:52 LaurieNevay verticalalignment
PDFpdf 20130222_0504_lws_xy_errbar_plot.pdf r1 manage 23.9 K 21 Feb 2013 - 20:52 LaurieNevay Collisions Again
PNGpng 20130222_0516_lws_xy_errbar_plot.png r1 manage 30.2 K 21 Feb 2013 - 20:53 LaurieNevay Horizontal
PNGpng 20130222_0522_lws_xy_fit_plot.png r1 manage 51.1 K 21 Feb 2013 - 20:54 LaurieNevay Phase Laserwire Scan
PNGpng 20130222_0526_lws_xy_fit_plot1.png r1 manage 57.7 K 21 Feb 2013 - 20:54 LaurieNevay Non Linear Scan 1
PNGpng 20130222_0543_lws_xy_fit_plot.png r1 manage 58.8 K 21 Feb 2013 - 21:43 LaurieNevay Repeated Nonlinear Scan
PNGpng 20130222_0543_lws_xy_fit_plot1.png r1 manage 59.5 K 21 Feb 2013 - 21:44 LaurieNevay Laser and Charge Normalised
PNGpng 20130222_0543_lws_xy_fit_plot3.png r1 manage 59.5 K 21 Feb 2013 - 21:55 LaurieNevay Fitting again
PNGpng 20130222_0543_sigma_comparison.png r1 manage 72.2 K 21 Feb 2013 - 21:56 LaurieNevay Sigma Comparison
PNGpng 20130222_0559_lws_xy_fit_plot.png r1 manage 55.9 K 21 Feb 2013 - 22:07 LaurieNevay Suspiciously Small...
PNGpng 20130222_0640_lws_xy_fit_plot1.png r1 manage 58.4 K 22 Feb 2013 - 00:40 LaurieNevay Initial Fit Plot Looks good...
PNGpng 20130222_0716_lws_xy_fit_plot.png r1 manage 57.0 K 22 Feb 2013 - 00:43 LaurieNevay Horizontal Scan
PNGpng 20130222_0818_lws_xy_fit_plot.png r1 manage 54.0 K 22 Feb 2013 - 00:44 LaurieNevay  
PNGpng 20130222_0828_lws_xy_fit_plot.png r1 manage 51.4 K 22 Feb 2013 - 00:45 LaurieNevay  
PNGpng 20130222_0838_lws_xy_fit_plot.png r1 manage 52.4 K 22 Feb 2013 - 00:46 LaurieNevay perhaps a little small
PNGpng _sigma_comparison1.png r1 manage 114.0 K 22 Feb 2013 - 00:41 LaurieNevay Sigma Comparison
PNGpng _sigma_comparison1_zoom2.png r1 manage 72.6 K 22 Feb 2013 - 00:42 LaurieNevay comparison zoom
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Topic revision: r9 - 28 Feb 2013 - LaurieNevay

 
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