Tags:
create new tag
view all tags

20130131 Shift

Plan

  • Detector gate check
  • Charge ramp -> signal correlation for both gate covering whole signal and gate covering only peak (quite narrow)
  • Load Lw optics
  • Roughly minimise background
  • Dispersion measurement / correction
  • BBA QM16,15,14FF
  • Check background
  • Reduce ipangle to < 100urad in both dimension

  • Detector off / switch to OTR mode (change otr switch position!)
  • Laser closed
  • OTR run for size - still no calibration! - relative to last week only
  • Quick OTR quad scan to optimise size at LWIP
  • Iterate with beam tuning and OTR until suitable

  • Switch to LW position on OTR/LW switch

  • Alignment using OTR screen for LW
  • Timing upstairs
  • Verify nothing on OTR camera with RGA only
  • Remove OTR screen
  • Ramp up laser

  • Optimise signal once found
  • Vertical->Phase->Horizontal->repeat

  • Good very long range horizontal scan
  • Vertical scan at peak
  • Vertical scan at various horizontal displacements 0,10,20,50,100um offset horizontally
  • Monitor orbit data to see horizontal position not drifting significantly!
  • Repeat horizontal scans in between if necessary and go to desired horizontal displacement

  • Quadrupole scan vertical
  • Skew quadrupole scan
  • Dispersion measurement / correction

On Shift

  • ATF2 extended by around 1 hour to study IPBSM.

  • set file before our operation set13jan31_1820.dat
  • set file set13jan31_1851.dat background around 3800, angle good at LWIP
  • 100 pulse log before otr - compare with a typical log last shift - 20130131_1852_log.dat

Date 25/01/2013 31/01/2013
ATF ICT 0.86x10^10 0.36x10^10
refc1amp 2054 1130
cherenkov 7609 3594

Using atf ict, there are 9983 ADC counts / 10^10e now and there was 8847 last time - around 12% higher, but quite close.

  • Switch to OTR mode. OTR switch position for otr is 310000. For laser-wire it's 512000
  • Detector off, screen at 5000.

Image immediately with no filter - centred on camera, however the brightness of image is quite low due to low charge. Our initial background correlation scan with atf optics didn't show a strong correlation as the machine was optimised for low charge. Alex retuned linac 8 timing and phase for higher transmission with gun laser intensity now set to 15%. Charge around 0.6x10^10 in the extraction line. Additionally, matching in linac as well as steering to BT to increase transmission so will have to do background comparison later.

Positions saved with OTR image found - 20130131_1932_pos.dat

  • Took access to fix energy meter.
  • Laser focus now at manipulator 8790.
  • Aligned using wire scanner detector and otr screen.
  • Timing was initially bad, but used extra length of cable to achieve necessary phase shift and therefore overlap at 5V in the range of the phase shifter.
  • Switch to high power setup, ramped up power
  • Regen output a bit low - around 10mJ but useable - therefore can go a little lower on flash lamps. Set to 80us delay.
  • Adjusted photodiode gate due to shift in timing. Gate is quite narrow to minimise background so will need to be adjusted when timing is changed a lot.

  • lwScan> 20130131_2144_lws axis=chahor, npulse=5.0, start=1000.0, stop=0.0, nstep=20.0
  • lwScan> 20130131_2152_lws axis=chaver, npulse=5.0, start=300.0, stop=0.0, nstep=15.0
  • lwScan> 20130131_2157_lws axis=chahor, npulse=5.0, start=300.0, stop=700.0, nstep=15.0
  • lwScan> 20130131_2201_lws axis=chaver, npulse=5.0, start=0.0, stop=500.0, nstep=30.0

Horizontal Alignment Vertical Alignment
20130131_2144_lws_xy_fit_plot1.png 20130131_2201_lws_xy_errbar_plot1.png
Phase Scan Pulse Height Phase Scan Pulse Width
20130131_2326_lws_xy_fit_plot1.png 20130131_2326_lws_xy_errbar_plot1.png

  • Collisions found! Small, but there

  • lwPos> Positions saved 20130131_2205_pos
  • lwPos> Positions saved 20130131_2228_pos
  • lwScan> 20130131_2326_lws axis=phasev, npulse=10.0, start=0.0, stop=5.0, nstep=20.0
  • lwScan> 20130131_2332_lws axis=phasev, npulse=10.0, start=10.0, stop=0.0, nstep=30.0
  • lwScan> 20130131_2341_lws axis=chaver, npulse=5.0, start=-200.0, stop=200.0, nstep=30.0
  • lwScan> 20130131_2348_lws axis=chaver, npulse=5.0, start=50.0, stop=-100.0, nstep=30.0
  • lwPos> Positions saved 20130131_2350_pos
  • lwScan> 20130201_0001_lws axis=chaver, npulse=10.0, start=-50.0, stop=150.0, nstep=40.0
  • lwScan> 20130201_0009_lws axis=chaver, npulse=10.0, start=-50.0, stop=150.0, nstep=40.0

20130201_0009_lws_xy_fit_plot.png

First Scan

  • lwScan> 20130201_0014_lws axis=phasev, npulse=10.0, start=2.5, stop=7.5, nstep=20.0
  • lwScan> 20130201_0018_lws axis=chaver, npulse=10.0, start=-10.0, stop=50.0, nstep=30.0
  • lwPos> Positions saved 20130201_0025_pos
  • lwScan> 20130201_0026_lws axis=chahor, npulse=10.0, start=800.0, stop=200.0, nstep=50.0

20130201_0041_lws_xy_errbar_plot.png

First horizontal Scan

  • lwScan> 20130201_0041_lws axis=chahor, npulse=10.0, start=1500.0, stop=-1000.0, nstep=40.0
  • lwScan> 20130201_0056_lws axis=chaver, npulse=10.0, start=-85.0, stop=115.0, nstep=41.0
  • lwScan> 20130201_0107_lws axis=chaver, npulse=20.0, start=-85.0, stop=115.0, nstep=41.0
  • lwScan> 20130201_0133_lws axis=chaver, npulse=20.0, start=0.0, stop=30.0, nstep=20.0
  • lwScan> 20130201_0142_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0145_lws axis=chaver, npulse=3.0, start=0.0, stop=30.0, nstep=20
  • lwScan> 20130201_0146_lws axis=chaver, npulse=30.0, start=-85.9473475391, stop=114.052652461, nstep=21.0

File access over network incredibly slow - scripts can't access files! Running firefox over ssh seems to worsen this. Closed it so no easy scan updates for now. Will update tomorrow.

Tweaked green output of laser and average pulse energy went up around 30%. Alex also needed to flip the phase of Modulator #0, which made us loose beam for a wee bit. Reoptimise afterwards. Vertical, phase, horizontal and repeat. Horizontal position has moved slightly to 323. Best vertical is still around 15 - very close to chamber 0 and bpm 0 with relatively flat beam.

  • Vertical scan at 0223 - sigma 2.41 +- 0.49. Signal to noise around 5:1.

  • Logs for laser energy correlation and charge correlation - sweep laser energy and machine charge over 1000 pulse logs.

20130201_0107_lws_xy_fit_plot1.png

1st Proper LW Scan

20130201_0233_log_bpm_plot_local7.png

Local BPMs

Correlations

Laser Energy and Photodiode Cherenkov vs Laser Energy
20130201_0233_log_xy_scatter_plot4.png 20130201_0233_log_xy_scatter_plot7.png
Cherenkov vs Laser Photodiode Cherenkov Charge Correlation
20130201_0233_log_xy_scatter_plot8.png 20130201_0240_log_xy_scatter_plot4.png

Many scans between 2am and 3am, however beam became more and more unstable. Fukuda-san tuned, which greatly improved transmission and doubled charge, but was intermittent so stopped scanning and waited. However, signal was barely noticeable about 0.5 hours later and in the end spent from 4am to 6am trying to recover signal.

20130201_0253_lws_xy_fit_plot.png

Tuning During a Scan!!!

Tried many scans. In a similar location. Due to the tuning, the beam had shifted in position by around 200um in both dimensions and by around 100urad in angle in both dimensions. Reset to where it was before, but still nothing.

Turned down laser and aligned spatially using otr screen again and wire scanner detector. Best vertical setting was around chamber vertical at +170um - around 130um different from before.

  • 06:00

Still no signal after many scans. Restart whole process. OTR images show beam is similar to best setting earlier. Go to timing, then spatial alignment and then try for collisions again.

Found timing was out quite a bit. Perhaps the machine had changed or the laser had slipped. Realigned laser-wire spatially and temporally. Found collisions again quickly. Optimised quickly.

  • High resolution vertical scan - 1.32 +- 0.14um
  • 1000 pulse logs on peak with and without laser
  • Long range horizontal scan
  • Ultra high resolution scan - 100 points, 40 samples

20130201_0641_lws_xy_fit_plot2.png

High Resolution LW Scan

20130201_0707_lws_xy_fit_plot2.png

Long Range Horizontal

  • Set file saved for machine - set13feb01_0659.dat

Quad Scan

QM14FF Current File Plot
-80.00 20130201_0828_lws 20130201_0828_lws_xy_fit_plot1.png
-85.00 20130201_0817_lws 20130201_0817_lws_xy_fit_plot1.png
-90.655 20130201_0800_lws 20130201_0800_lws_xy_fit_plot3.png
-95.00 20130201_0847_lws 20130201_0847_lws_xy_fit_plot.png
-100.00 20130201_0859_lws 20130201_0859_lws_xy_fit_plot4.png

Both laserwire and otr at the same points. A quick vertical scan was made at each new magnet current for the laserwire as the beam moved vertically slightly.

Full History List

  • lwLog> 20130130_1746_log npulse=1000.0
  • lwPos> Positions saved 20130131_1552_pos
  • lwLog> 20130131_1818_log npulse=1000.0
  • lwLog> 20130131_1852_log npulse=100.0
  • lwPos> Positions saved 20130131_1932_pos
  • lwScan> 20130131_2144_lws axis=chahor, npulse=5.0, start=1000.0, stop=0.0, nstep=20.0
  • lwScan> 20130131_2152_lws axis=chaver, npulse=5.0, start=300.0, stop=0.0, nstep=15.0
  • lwScan> 20130131_2157_lws axis=chahor, npulse=5.0, start=300.0, stop=700.0, nstep=15.0
  • lwScan> 20130131_2201_lws axis=chaver, npulse=5.0, start=0.0, stop=500.0, nstep=30.0
  • lwPos> Positions saved 20130131_2205_pos
  • lwPos> Positions saved 20130131_2228_pos
  • lwScan> 20130131_2326_lws axis=phasev, npulse=10.0, start=0.0, stop=5.0, nstep=20.0
  • lwScan> 20130131_2332_lws axis=phasev, npulse=10.0, start=10.0, stop=0.0, nstep=30.0
  • lwScan> 20130131_2341_lws axis=chaver, npulse=5.0, start=-200.0, stop=200.0, nstep=30.0
  • lwScan> 20130131_2348_lws axis=chaver, npulse=5.0, start=50.0, stop=-100.0, nstep=30.0
  • lwPos> Positions saved 20130131_2350_pos
  • lwScan> 20130201_0001_lws axis=chaver, npulse=10.0, start=-50.0, stop=150.0, nstep=40.0
  • lwScan> 20130201_0009_lws axis=chaver, npulse=10.0, start=-50.0, stop=150.0, nstep=40.0
  • lwScan> 20130201_0014_lws axis=phasev, npulse=10.0, start=2.5, stop=7.5, nstep=20.0
  • lwScan> 20130201_0018_lws axis=chaver, npulse=10.0, start=-10.0, stop=50.0, nstep=30.0
  • lwPos> Positions saved 20130201_0025_pos
  • lwScan> 20130201_0026_lws axis=chahor, npulse=10.0, start=800.0, stop=200.0, nstep=50.0
  • lwScan> 20130201_0041_lws axis=chahor, npulse=10.0, start=1500.0, stop=-1000.0, nstep=40.0
  • lwScan> 20130201_0056_lws axis=chaver, npulse=10.0, start=-85.0, stop=115.0, nstep=41.0
  • lwScan> 20130201_0107_lws axis=chaver, npulse=20.0, start=-85.0, stop=115.0, nstep=41.0
  • lwScan> 20130201_0133_lws axis=chaver, npulse=20.0, start=0.0, stop=30.0, nstep=20.0
  • lwScan> 20130201_0142_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0145_lws axis=chaver, npulse=3.0, start=0.0, stop=30.0, nstep=20
  • lwScan> 20130201_0146_lws axis=chaver, npulse=30.0, start=-85.9473475391, stop=114.052652461, nstep=21.0
  • lwScan> 20130201_0154_lws axis=chaver, npulse=3.0, start=0.0, stop=30.0, nstep=20
  • lwScan> 20130201_0155_lws axis=chaver, npulse=20.0, start=-84.7835504914, stop=115.216449509, nstep=41.0
  • lwScan> 20130201_0203_lws axis=chahor, npulse=20.0, start=1000.0, stop=-500.0, nstep=40.0
  • lwScan> 20130201_0223_lws axis=chaver, npulse=20.0, start=-85.0, stop=115.0, nstep=41.0
  • lwLog> 20130201_0233_log npulse=1000.0
  • lwLog> 20130201_0240_log npulse=1000.0
  • lwScan> 20130201_0247_lws axis=chaver, npulse=20.0, start=-85.0, stop=115.0, nstep=41.0
  • lwScan> 20130201_0253_lws axis=chaver, npulse=20.0, start=-82.7, stop=117.3, nstep=101.0
  • lwLog> 20130201_0257_log npulse=100.0
  • lwScan> 20130201_0344_lws axis=chaver, npulse=20.0, start=-20.0, stop=50.0, nstep=40.0
  • lwScan> 20130201_0350_lws axis=phasev, npulse=20.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0355_lws axis=chahor, npulse=10.0, start=-500.0, stop=1000.0, nstep=30.0
  • lwScan> 20130201_0407_lws axis=chaver, npulse=10.0, start=50.0, stop=-50.0, nstep=30.0
  • lwScan> 20130201_0410_lws axis=chaver, npulse=10.0, start=10.0, stop=25.0, nstep=10.0
  • lwScan> 20130201_0427_lws axis=chaver, npulse=10.0, start=10.0, stop=25.0, nstep=10.0
  • lwScan> 20130201_0433_lws axis=chaver, npulse=10.0, start=10.0, stop=25.0, nstep=10.0
  • lwScan> 20130201_0437_lws axis=chaver, npulse=10.0, start=-50.0, stop=100.0, nstep=25.0
  • lwScan> 20130201_0440_lws axis=chaver, npulse=10.0, start=40.0, stop=70.0, nstep=10.0
  • lwScan> 20130201_0441_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0448_lws axis=chaver, npulse=10.0, start=-100.0, stop=100.0, nstep=40.0
  • lwScan> 20130201_0454_lws axis=chaver, npulse=10.0, start=-100.0, stop=100.0, nstep=40.0
  • lwScan> 20130201_0458_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=30.0
  • lwScan> 20130201_0508_lws axis=chaver, npulse=10.0, start=-200.0, stop=400.0, nstep=50.0
  • lwScan> 20130201_0514_lws axis=chahor, npulse=10.0, start=500.0, stop=0.0, nstep=20.0
  • lwScan> 20130201_0521_lws axis=chaver, npulse=10.0, start=100.0, stop=200.0, nstep=20.0
  • lwPos> Positions saved 20130201_0536_pos
  • lwScan> 20130201_0601_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0604_lws axis=phasev, npulse=10.0, start=0.0, stop=10.0, nstep=20.0
  • lwScan> 20130201_0613_lws axis=chaver, npulse=5.0, start=-300.0, stop=300.0, nstep=20.0
  • lwScan> 20130201_0619_lws axis=chaver, npulse=10.0, start=20.0, stop=80.0, nstep=25.0
  • lwScan> 20130201_0621_lws axis=chaver, npulse=10.0, start=-49.0, stop=151.0, nstep=26.0
  • lwScan> 20130201_0625_lws axis=phasev, npulse=10.0, start=3.0, stop=6.0, nstep=9.0
  • lwScan> 20130201_0627_lws axis=chahor, npulse=10.0, start=1000.0, stop=-500.0, nstep=30.0
  • lwScan> 20130201_0635_lws axis=chaver, npulse=10.0, start=-49.0, stop=151.0, nstep=51.0
  • lwScan> 20130201_0641_lws axis=chaver, npulse=20.0, start=-49.0, stop=151.0, nstep=101.0
  • lwLog> 20130201_0655_log npulse=1000.0
  • lwPos> Positions saved 20130201_0700_pos
  • lwLog> 20130201_0700_log npulse=1000.0
  • lwScan> 20130201_0707_lws axis=chahor, npulse=10.0, start=1500.0, stop=-1500.0, nstep=100.0
  • lwScan> 20130201_0730_lws axis=chaver, npulse=3.0, start=38.0, stop=68.0, nstep=20
  • lwScan> 20130201_0731_lws axis=chaver, npulse=50.0, start=-49.2210809384, stop=150.778919062, nstep=101.0
  • lwScan> 20130201_0731_lws axis=chaver, npulse=50.0, start=-47.0, stop=153.0, nstep=101.0
  • lwScan> 20130201_0731_lws axis=chaver, npulse=50.0, start=-47.0, stop=153.0, nstep=101.0
  • lwScan> 20130201_0800_lws axis=chaver, npulse=20.0, start=-47.0, stop=153.0, nstep=71.0
  • lwScan> 20130201_0813_lws axis=chaver, npulse=10.0, start=0.0, stop=25.0, nstep=10.0
  • lwScan> 20130201_0814_lws axis=chaver, npulse=10.0, start=-79.0, stop=121.0, nstep=11.0
  • lwScan> 20130201_0817_lws axis=chaver, npulse=20.0, start=-79.0, stop=121.0, nstep=71.0
  • lwScan> 20130201_0827_lws axis=chaver, npulse=10.0, start=0.0, stop=-20.0, nstep=10.0
  • lwScan> 20130201_0828_lws axis=chaver, npulse=20.0, start=-106.3, stop=93.7, nstep=71.0
  • lwScan> 20130201_0840_lws axis=chaver, npulse=10.0, start=0.0, stop=-110.0, nstep=25.0
  • lwScan> 20130201_0843_lws axis=chaver, npulse=10.0, start=0.0, stop=-20.0, nstep=10.0
  • lwScan> 20130201_0846_lws axis=chaver, npulse=10.0, start=40.0, stop=80.0, nstep=10.0
  • lwScan> 20130201_0847_lws axis=chaver, npulse=20.0, start=-24.0, stop=176.0, nstep=71.0
  • lwScan> 20130201_0858_lws axis=chaver, npulse=10.0, start=90.0, stop=110.0, nstep=10.0
  • lwScan> 20130201_0859_lws axis=chaver, npulse=20.0, start=0.0, stop=200.0, nstep=71.0
  • lwScan> 20130201_0910_lws axis=chaver, npulse=10.0, start=0.0, stop=-10.0, nstep=5.0
  • lwLog> 20130201_0911_log npulse=500.0
  • lwLog> 20130201_0914_log npulse=500.0
  • lwPos> Positions saved 20130201_0932_pos

Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng 20130131_2144_lws_xy_fit_plot1.png r1 manage 54.6 K 07 Feb 2013 - 04:12 LaurieNevay Horizontal Alignment
PNGpng 20130131_2201_lws_xy_errbar_plot1.png r1 manage 31.9 K 07 Feb 2013 - 04:13 LaurieNevay Vertical Alignment
PNGpng 20130131_2326_lws_xy_errbar_plot1.png r1 manage 22.7 K 07 Feb 2013 - 04:15 LaurieNevay Phase Scan Pulse Width
PNGpng 20130131_2326_lws_xy_fit_plot1.png r1 manage 48.9 K 07 Feb 2013 - 04:14 LaurieNevay Phase Scan
PNGpng 20130201_0009_lws_xy_fit_plot.png r1 manage 49.1 K 07 Feb 2013 - 04:16 LaurieNevay First Scan
PNGpng 20130201_0041_lws_xy_errbar_plot.png r1 manage 25.2 K 31 Jan 2013 - 15:55 KonstantinKruchinin Horizontal Scan
PNGpng 20130201_0107_lws_xy_fit_plot1.png r1 manage 42.1 K 07 Feb 2013 - 04:17 LaurieNevay 1st Proper LW Scan
PNGpng 20130201_0233_log_bpm_plot_local7.png r1 manage 162.4 K 07 Feb 2013 - 04:18 LaurieNevay Local BPMs
PNGpng 20130201_0233_log_xy_scatter_plot4.png r1 manage 51.0 K 07 Feb 2013 - 04:19 LaurieNevay Laser Energy and Photodiode Calibration
PNGpng 20130201_0233_log_xy_scatter_plot7.png r1 manage 44.6 K 07 Feb 2013 - 04:20 LaurieNevay Cherenkov vs Laser Energy
PNGpng 20130201_0233_log_xy_scatter_plot8.png r1 manage 44.2 K 07 Feb 2013 - 04:20 LaurieNevay Cherenkov vs Laser Photodiode
PNGpng 20130201_0240_log_xy_scatter_plot4.png r1 manage 49.1 K 07 Feb 2013 - 04:21 LaurieNevay Cherenkov Charge Correlation
PNGpng 20130201_0253_lws_xy_fit_plot.png r1 manage 46.7 K 07 Feb 2013 - 04:22 LaurieNevay Tuning During a Scan!!!
PNGpng 20130201_0641_lws_xy_fit_plot2.png r1 manage 56.8 K 07 Feb 2013 - 04:23 LaurieNevay High Resolution LW Scan
PNGpng 20130201_0707_lws_xy_errbar_plot.png r1 manage 33.5 K 04 Feb 2013 - 22:31 LaurieNevay 0707 Horizontal Scan
PNGpng 20130201_0707_lws_xy_fit_plot2.png r1 manage 61.1 K 07 Feb 2013 - 04:23 LaurieNevay Long Range Horizontal
PNGpng 20130201_0800_lws_xy_fit_plot3.png r1 manage 55.7 K 07 Feb 2013 - 04:25 LaurieNevay -90A
PNGpng 20130201_0817_lws_xy_fit_plot1.png r1 manage 54.9 K 07 Feb 2013 - 04:27 LaurieNevay -85A
PNGpng 20130201_0828_lws_xy_fit_plot1.png r1 manage 55.1 K 07 Feb 2013 - 04:28 LaurieNevay -80A
PNGpng 20130201_0847_lws_xy_fit_plot.png r1 manage 43.9 K 07 Feb 2013 - 04:29 LaurieNevay -95A
PNGpng 20130201_0859_lws_xy_fit_plot4.png r1 manage 55.7 K 07 Feb 2013 - 04:29 LaurieNevay -100A
Edit | Attach | Watch | Print version | History: r13 < r12 < r11 < r10 < r9 | Backlinks | Raw View | Raw edit | More topic actions

Physics WebpagesRHUL WebpagesCampus Connect • Royal Holloway, University of London, Egham, Surrey TW20 0EX; Tel/Fax +44 (0)1784 434455/437520

Topic revision: r13 - 07 Feb 2013 - LaurieNevay

 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 2008-2025 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding RHUL Physics Department TWiki? Send feedback