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20:00 Access for laser-wire alignment.

Beam on 22:30

Set File set12jun15_2250.dat

20120615 Shift

LN, SB, AA, YK, PK

Access from 8pm to 10:30pm to align LW and check with high power. Everything ok. Installed energy meter post ip and connected to BPM cable for use with NI digitiser.

Loading set file 12may22_0904.dat - last set file from end of last shift. Leave beginning of extraction line as it is - more recent extraction and only change matching section to achieve small beam size at our location.

TD2 for ADC gates had been changed! Reset to nominal value. Background around 6000 ADC counts for charge of around 0.4 x 10^10 (1000 ADC counts on REFC1:amp). This is approximately the same background level as before but with half the charge - therefore double the background level. Switched straight to OTR to confirm beam size before tuning. Usually, the background can be reduced by tweaking the quadrupoles post LWIP slightly making large differences to background.

Set file set12jun15_2359.dat

OTR found. Lower wavelength filter better, but lower transmissiona and lower QE of camera.

Vertical Beam size from OTR 2.1um. Background around 4500 ADC counts on LW Detector with 10dB Attenuation.

Used screen to profile laser beam and observed using APD detector. Laser beam focus location is 9050um (within 10um). Horizontal and vertical alignment performed. Best Location H:300um V:670um. Phase scan showed overlap around 0 and 10V at the edge of the voltage controlled phase shifter's range. Therefore, I removed the 10cm cable previously introduced for extra phase

  • lwScan> 20120616_0224_lws axis=phasev, npulse=5.0, start=0.0, stop=10.0, nstep=30.0
  • lwScan> 20120616_0227_lws axis=phasev, npulse=5.0, start=0.0, stop=10.0, nstep=30.0
  • lwScan> 20120616_0236_lws axis=phasev, npulse=5.0, start=0.0, stop=10.0, nstep=30.0
  • lwScan> 20120616_0248_lws axis=chaver, npulse=2.0, start=600.0, stop=700.0, nstep=30.0
  • lwScan> 20120616_0253_lws axis=chaver, npulse=2.0, start=640.0, stop=720.0, nstep=30.0
  • lwScan> 20120616_0258_lws axis=chaver, npulse=3.0, start=582.0, stop=782.0, nstep=51.0
  • lwScan> 20120616_0303_lws axis=chahor, npulse=3.0, start=1000.0, stop=-800.0, nstep=60.0
  • lwScan> 20120616_0316_lws axis=phasev, npulse=5.0, start=0.0, stop=10.0, nstep=30.0
  • lwLog> 20120616_0321_log npulse=200.0 - on peak correlation
  • lwLog> 20120616_0324_log npulse=200.0 - off peak and no laser correlation

On peak correlation log shows 0.54 correlation between charge and signal Off peak correlation log shows 0.897 correlation between charge and signal

Vertical scans for different laser focus positions using chamber horizontal motion

  • lwScan> 20120616_0337_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=208
  • lwScan> 20120616_0409_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=0

Changed to 4dB of attenution
Large modulation again - scan really horrible - timing. Increased delay by 1 RF bucket and now phase scanning.

  • lwScan> 20120616_0419_lws axis=phasev, npulse=5.0, start=0.0, stop=10.0, nstep=30.0
  • lwScan> 20120616_0426_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=-0.6
  • lwScan> 20120616_0437_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor= 100
  • lwScan> 20120616_0449_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=-100
  • lwScan> 20120616_0459_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=-200
  • lwScan> 20120616_0510_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=300
  • lwScan> 20120616_0518_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; chahor=400
  • lwScan> 20120616_0528_lws axis=chaver, npulse=5.0, start=581.0, stop=781.0, nstep=101.0 ; chahor=500
  • lwScan> 20120616_0538_lws axis=chaver, npulse=5.0, start=581.0, stop=781.0, nstep=101.0

20120616_WaistMontage.jpg

Background and laser correlation study

  • lwLog> 20120616_0613_log npulse=500.0 - about 1.5um off peak
  • lwLog> 20120616_0620_log npulse=500.0 - on peak
  • lwLog> 20120616_0626_log npulse=500.0 - about 5um off peak (background, laser off)

Scan at centre reproducibility

  • lwScan> 20120616_0633_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0 ; problem with gun RF, radn interlock, reset then ok
  • lwScan> 20120616_0647_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0
  • lwScan> 20120616_0655_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0

Quadrupele scan

Quad quick vertical quick horizontal data
-89.2620     20120616_0655_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0
-79.2620 v=686, sv=4.53 h=207, sh=207 20120616_0734_lws axis=chaver, npulse=5.0, start=586.0, stop=786.0, nstep=101.0
-81.260 v=673, sv=5.06 h=199, sh=201 20120616_0758_lws axis=chaver, npulse=5.0, start=573.0, stop=773.0, nstep=101.0
-83.260 v=677, sv=6.76 h=193, sh=206 20120616_0820_lws axis=chaver, npulse=5.0, start=577.0, stop=777.0, nstep=101.0
-85.260 v=679, sv=6.44 h=184, sh=209 20120616_0841_lws axis=chaver, npulse=5.0, start=579.0, stop=779.0, nstep=101.0
-87.260 v=681, sv=3.81 h=253, sh=217 20120616_0911_lws axis=chaver, npulse=5.0, start=581.0, stop=781.0, nstep=101.0
-89.260 v=683, sv=8.12 h=213, sh=192 20120616_0934_lws axis=chaver, npulse=5.0, start=583.0, stop=783.0, nstep=101.0
-91.260 v=684, sv=3.90 h=226, sh=212 20120616_0957_lws axis=chaver, npulse=5.0, start=584.0, stop=784.0, nstep=101.0

Background and laser correlation study

  • lwLog> 20120616_1006_log npulse=500.0
  • lwLog> 20120616_1011_log npulse=500.0

  • lwPos> Positions saved 20120616_1011_pos
  • set12jun16_1012.dat

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Topic revision: r1 - 16 Jun 2012 - StewartBoogert

 
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