IAC 2-29-08

From New IAC Wiki
Jump to navigation Jump to search

Leap Day run

DC setup

This time the Sense wire HV is set to 1500 to start

90/10 ArCo2

HV settings
Wire Volts current ([math]\mu[/math]A)
Sense 1500
Field -750
Guard 750

DC preamp at 5.6 Volts


Beam Line Configuration

A 1/4 inch diameter collimater is placed in the experimental cell just after a Helium bag inserted in the wall. A 2 cm thick scintillator is place over the beam downstream side of the collimator aligned using a laser. A 3mm diameter collimator is placed just before a 1 kG magnet that is after the DC. The 1 kG magnet placed after the drift chambers deflects charged particles onto a large scintillator paddle.

A logic circuit was set up to allow for the following trigger configurations

  1. gun AND (Front Scint OR Rear Scint)
  2. gun AND (Front Scint AND Rear Scint)

Increased beam energy from 10 MeV to 12 MeV due to expected energy loss in front scintillator.


Data was taken with

  1. Metallica's output is recorded in the odd ADC numbered ntuple entries (ADC1, ADC3,ADC5, ...)
  2. Plastika's output is recorded in the EVEN ADC numbered ntuple entries (ADC2,ADC4,ADC6,...)
  3. Wire # 4 is recored in ADC7 for Metalica and 8 for Plastica.
  4. Wire # 3 is beam upstream
  5. The DAQ trigger was gun AND (Front Scint OR Rear Scint). The back scintillator output is in the data stream (ADC14 in C-convention, ADC15 in ntuple) so A software coincidence will be used. The rate with ANDing all signals was time prohibitive.


Exp setup IAC 2 28 08.jpg Exp setup IAC 2 28 08 2.jpg

DC Apparatus 2-2-29-08.jpg DC Apparatus 1-2-29-08.jpg DC Apparatus 1kgMag-2-29-08.jpg DC LaserAlignment-2-29-08.jpg

Runs

Run Description

Decided to increase beam current until up to 10% of events in front scintilaltor pass through magnet after drift chamber and hit back scintillator. Ran in OR mode so a software coincidence can be formed based on measurement in ADC15 (ADC14 in C convention).

Run # Description
431 0" from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
432 0" from feedthrough , Sense wire at 1500 Volts, Metalica (ADC6; C-convention) sees overflows and looks hot on scope compared to Plastika (ADC8: in ntuples),Gun voltage at 1.76
433 -1" from feedthrough (beam should miss chamber), Sense wire at 1500 Volts, I see peds in Plastika but not metalica (Metalica is beam upstream of Plastika), The overflows are due to DC voltage/Gain being too high ,Gun voltage at 1.76
434 1" from feedthrough , Sense wire at 1500 Volts, Gun voltage at 1.76
435 2" from feedthrough , Sense wire at 1500 Volts, Gun voltage at 1.76

Histograms

Change voltage on DC to values used on last day of January run 90/10 ArCo2

Drift Chamber HV

HV settings
Cable # Volts Current (ma)
Sense +1450
Field -725
Guard +725
Front Scint -1127 30 mV threshold
Rear Scint -1153 81 mV Threshold


Run # Scint counts > 70 channels (ADC15) Scint counts/trigger Description
436 2" (-100k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76, Less overflows in Metalica ADC
437 4" (-200k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
438 1" (-50k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76, visually inspected position and confirmed it was 1" from feedthrough
439 0.5" (-25k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
440 0.25" (-12.5k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
441 0.0625" (-9.375k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
442 -5" (+240.625k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76, try to get electrons missing chamber, use ADC14 to cut on electrons hitting back scintillator. ADC7 should be zero if its really an electron.
443 -3" (+140.625k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
444 -2" (+90.625k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
445 -0.5" (+15.625k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
446 -0.25" (+3.125k) from feedthrough , Sense wire at 1450 Volts, Gun voltage at 1.76
447 Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply On, Preamp Power supply at 5.6 V, trigger: gun OR either scintillator
448 Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off
449 Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off, DC preamp off
450 Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off, DC pramp off, Now just trigger on gun pulse, DC HV off


Run # r436 r437 r438 r439 r440 r441 r442 r443 r444 r445 r446
Distance(inch) 2" 4" 1" 0.5" 0.25" 0.0625" -5" -3" -2" -0.5 -0.25"
ADC15 ADC15 r436 r447.gif ADC15 r436 r447 1.gif ADC15 r437 r447.gif ADC15 r437 r447 1.gif ADC15 r438 r447.gif ADC15 r438 r447 1.gif ADC15 r439 r447.gif ADC15 r439 r447 1.gif ADC15 r440 r447.gif ADC15 r440 r447 1.gif ADC15 r441 r447.gif ADC15 r441 r447 1.gif ADC15 r442 r447.gif ADC15 r442 r447 1.gif ADC15 r443 r447.gif ADC15 r443 r447 1.gif ADC15 r444 r447.gif ADC15 r444 r447 1.gif ADC15 r445 r447.gif ADC15 r445 r447 1.gif ADC15 r446 r447.gif ADC15 r446 r447 1.gif
3 ADC3 r436 with cut landau fit.gif ADC3 r437 with cut landau fit.gif ADC3 r438 with cut landau fit.gif ADC3 r439 with cut landau fit.gif ADC3 r440 with cut landau fit.gif ADC3 r441 with cut landau fit.gif ADC3 r442 with cut landau fit.gif ADC3 r443 with cut landau fit.gif ADC3 r444 with cut landau fit.gif ADC3 r445 with cut landau fit.gif ADC3 r446 with cut landau fit.gif
4 ADC4 r436 with cut landau fit.gif ADC4 r437 with cut landau fit.gif ADC4 r438 with cut landau fit.gif ADC4 r439 with cut landau fit.gif ADC4 r440 with cut landau fit.gif ADC4 r441 with cut landau fit.gif ADC4 r442 with cut landau fit.gif ADC4 r443 with cut landau fit.gif ADC4 r444 with cut landau fit.gif ADC4 r445 with cut landau fit.gif ADC4 r446 with cut landau fit.gif
5 ADC5 r436 with cut landau fit.gif ADC5 r437 with cut landau fit.gif ADC5 r438 with cut landau fit.gif ADC5 r439 with cut landau fit.gif ADC5 r440 with cut landau fit.gif ADC5 r441 with cut landau fit.gif ADC5 r442 with cut landau fit.gif ADC5 r443 with cut landau fit.gif ADC5 r444 with cut landau fit.gif ADC5 r445 with cut landau fit.gif ADC5 r446 with cut landau fit.gif
6 ADC6 r436 with cut gauss fit.gif ADC6 r437 with cut gauss fit.gif ADC6 r438 with cut gauss fit.gif ADC6 r439 with cut gauss fit.gif ADC6 r440 with cut gauss fit.gif ADC6 r441 with cut gauss fit.gif ADC6 r442 with cut gauss fit.gif ADC6 r443 with cut gauss fit.gif ADC6 r444 with cut gauss fit.gif ADC6 r445 with cut gauss fit.gif ADC6 r446 with cut gauss fit.gif
7 ADC7 r436 with cut landau fit.gif ADC7 r437 with cut landau fit.gif ADC7 r438 with cut landau fit.gif ADC7 r439 with cut landau fit.gif ADC7 r440 with cut landau fit.gif ADC7 r441 with cut landau fit.gif ADC7 r442 with cut landau fit.gif ADC7 r443 with cut landau fit.gif ADC7 r444 with cut landau fit.gif ADC7 r445 with cut landau fit.gif ADC7 r446 with cut landau fit.gif
8 ADC8 r436 with cut landau fit.gif ADC8 r437 with cut landau fit.gif ADC8 r438 with cut landau fit.gif ADC8 r439 with cut landau fit.gif ADC8 r440 with cut landau fit.gif ADC8 r441 with cut landau fit.gif ADC8 r442 with cut landau fit.gif ADC8 r443 with cut landau fit.gif ADC8 r444 with cut landau fit.gif ADC8 r445 with cut landau fit.gif ADC8 r446 with cut landau fit.gif
9 ADC9 r436 with cut landau fit.gif ADC9 r437 with cut gauss fit.gif ADC9 r438 with cut gauss fit.gif ADC9 r439 with cut gauss fit.gif ADC9 r440 with cut gauss fit.gif ADC9 r441 with cut gauss fit.gif ADC9 r442 with cut gauss fit.gif ADC9 r443 with cut gauss fit.gif ADC9 r444 with cut gauss fit.gif ADC9 r445 with cut gauss fit.gif ADC9 r446 with cut gauss fit.gif
10 ADC10 r436 with cut landau fit.gif ADC10 r437 with cut landau fit.gif ADC10 r438 with cut landau fit.gif ADC10 r439 with cut landau fit.gif ADC10 r440 with cut landau fit.gif ADC10 r441 with cut landau fit.gif ADC10 r442 with cut landau fit.gif ADC10 r443 with cut landau fit.gif ADC10 r444 with cut landau fit.gif ADC10 r445 with cut landau fit.gif ADC10 r446 with cut landau fit.gif
11 ADC11 r436 with cut landau fit.gif ADC11 r437 with cut landau fit.gif ADC11 r438 with cut landau fit.gif ADC11 r439 with cut landau fit.gif ADC11 r440 with cut landau fit.gif ADC11 r441 with cut landau fit.gif ADC11 r442 with cut landau fit.gif ADC11 r443 with cut landau fit.gif ADC11 r444 with cut landau fit.gif ADC11 r445 with cut landau fit.gif ADC11 r446 with cut landau fit.gif
12 ADC12 r436 with cut landau fit.gif ADC12 r437 with cut landau fit.gif ADC12 r438 with cut landau fit.gif ADC12 r439 with cut landau fit.gif ADC12 r440 with cut landau fit.gif ADC12 r441 with cut landau fit.gif ADC12 r442 with cut landau fit.gif ADC12 r443 with cut landau fit.gif ADC12 r444 with cut landau fit.gif ADC12 r445 with cut landau fit.gif ADC12 r446 with cut landau fit.gif
ADC3 Mean Value ADC4 Mean Value ADC5 Mean Value ADC6 Mean Value ADC7 Mean Value ADC8 Mean Value ADC9 Mean Value ADC10 Mean Value ADC11 Mean Value ADC12 Mean Value
Distance(inch)
2" 311.7+/-8.9 (607.4) 452.4+/-8.8 457.6+/-11.4 (781.3) 986.4+/-4.0 (996.6) 314.8+/-7.5 (582.8) 342.6+/-8.7 (602.8) ? 336.7+/-7.4 (613.6) 344.9+/-9.4 (634.8) 477.3+/-10.1 (773.6)
4" 459.2+/-16.0 (848) 619+/-14.4 (1033) 667.2+/-18.4 (1109) 1029+/-4.8 (1037) 413+/-10.9 (764.3) 490.5+/-13.7 (896.3) ? 451.3+/-12.6 (803.9) 502.5+/-14.3 (891.4) 647.7+/-15.9 (1040)
1" 477.6+/-17.9 (933.1) 617.9+/-14.0 (997) 666.5+/-17.5 (1049) 1116+/-6.3 (1122) 448.1+/-11.8 (834.2) 509.4+/-16.1 (912.8) ? 478.8+/-12.8 (837.5) 501+/-16.4 (930) 644.7+/-16.1 (1065)
0.5" 501.5+/-17.2 (9483) 655.2+/-16.0 (1045) 641.2+/-18.2 (1085) 1079+/-5.0 (1082) 465.5+/-11.8 (844.3) 542.7+/-17.1 (936.2) ? 481.1+/-13.6 (834.2) 536.9+/-14.7 (918.2) 662+/-16.5 (1070)
0.25" 437.6+/-15.0 (849.3) 587.1+/-14.0 (1012) 653.5+/-17.9 (1074) 1011+/-4.6 (1021) 409.6+/-11.8 (770.6) 481.9+/-15.1 (864.1) ? 450.3+/-13.1 (773.3) 478.3+/-16.7 (886.7) 598.2+/-16.0 (1005)
0.0625" 474.9+/-23.9 (838.8) 628+/-26.6 (999.2) 609.1+/-28.9 (1036) 1021+/-8.2 (1032) 451.3+/-15.5 (771.1) 477.7+/-21.4 (902.2) ? 467.3+/-24.4 (817.7) 497+/-24.5 (875.5) 656.4+/-30.7 (1076)
-5" 138.3+/-9.5 (470.4) 302.2+/-4.9 (592.1) 295.9+/-5.6 (606.9) 788.6+/-3.8 (786.1) 235.7+/-3.6 (468) 201.6+/-4.8 (464) ? 197.7+/-3.6 (435.8) 156.1+/-12.6 (497) 319.3+/-5.0 (606.2)
-3" 67.38+/-14.25 (551.5) 310.8+/-3.7 (637.5) 334.1+/-4.6 (692.6) 732.5+/-1.6 (733.8) 248.3+/-2.8 (547.7) 184.4+/-4.8 (535.3) ? 187+/-3.5 (497.6) 210+/-3.9 (564.8) 332.5+/-3.7 (660.2)
-2" 99.18+/-20.43 (669.9) 373.5+/-5.7 (763.3) 415+/-6.6 (830.2) 750.6+/-2.0 (753.8) 299.6+/-4.2 (661.4) 238+/-6.6 (657.7) ? 219.9+/-5.2 (580.2) 235.5+/-7.4 (672.6) 400.9+/-5.2 (772)
-0.5" 137.7+/-16.5 (695.5) 400.8+/-5.2 (810) 455.6+/-6.4 (896.7) 760.9+/-1.9 (763) 308.9+/-4.0 (681.5) 259.9+/-6.5 (699.5) ? 238.1+/-5.7 (627.6) 266.6+/-6.8 (710.8) 431.2+/-5.2 (829.6)
-0.25" 215+/-16.3 (776.2) 436.2+/-6.2 (871.1) 498.3+/-7.5 (966) 772.7+/-2.1 (777.7) 349.5+/-5.2 (766.4) 304.8+/-7.9 (762.1) ? 276.8+/-6.3 (674.6) 309.7+/-8.0 (781.6) 489.2+/-6.4 (920.7)

ADC output -vs- distance Plots

Metalica's output is shown in BLACK and Plastika in RED.
Wire #2

Distance vs mean value of ADC3 ADC4.jpgDistance vs mean value of ADC3 ADC4 1.jpg

Wire #3

Distance vs mean value of ADC5 ADC6.jpgDistance vs mean value of ADC5 ADC6 1.jpg

Wire #4

Distance vs mean value of ADC7 ADC8.jpgDistance vs mean value of ADC7 ADC8 1.jpg

Wire # 6

Distance vs mean value of ADC11 ADC12.jpgDistance vs mean value of ADC11 ADC12 1.jpg

Observations

A BIASED fit to Wire #4

BiasedFit2Wire4 2-29-08.jpg

A dependence of the DC's measured charge as a function of position was NOT observed; the slopes are consistent with zero. Plastika outputs 50 ADC channels (100 fC / channel) more than Metalica. Is this because it was behind Metalica?

A Landau fit to the charge distributions of Wire 4 for Metalica and Plastika, when the beam is 4 inches away from the feed through, gave a sigma of 122 for Metalica and a sigma of 160 for Plastika. The sigma of Landau fits to Plastika's ADC spectrum were always 30% larger than Metalica as you can see from the histograms above. The exception is at the 2" measurement position in which the sigmas differed by 10%.



Media:Wire_position_ADC3_xmgrace.txt
Media:Wire_position_ADC4_xmgrace.txt
Media:Wire_position_ADC5_xmgrace.txt
Media:Wire_position_ADC6_xmgrace.txt
Media:Wire_position_ADC7_xmgrace.txt
Media:Wire_position_ADC8_xmgrace.txt
Media:Wire_position_ADC10_xmgrace.txt
Media:Wire_position_ADC11_xmgrace.txt
Media:Wire_position_ADC12_xmgrace.txt

Gain change

The histograms below represent a comparison between two runs with different Drift chamber HV settings.


ADC # r434_r438 HV = 1500 r435_r436 HV = + 1450
15 R434 r438 ADC15.gif R435 r436 ADC15 1.gif
4 R434 r438 ADC4.gif R435 r436 ADC4.gif
5 R434 r438 ADC5.gif R435 r436 ADC5.gif
6 R434 r438 ADC6.gif R435 r436 ADC6.gif
7 R434 r438 ADC7.gif R435 r436 ADC7.gif
8 R434 r438 ADC8.gif R435 r436 ADC8.gif
10 R434 r438 ADC10.gif R435 r436 ADC10.gif
11 R434 r438 ADC11.gif R435 r436 ADC11.gif
12 R434 r438 ADC12.gif R435 r436 ADC12.gif

The histograms below have following cut: ADC15>70 and ADC15<100.

ADC # r434_r438(ADC15>70 && ADC15<100) r435_r436(ADC15>70 && ADC15<100)
4 R434 r438 ADC4 with cut.gif R435 r436 ADC4 with cut.gif
5 R434 r438 ADC5 with cut.gif R435 r436 ADC5 with cut.gif
6 R434 r438 ADC6 with cut.gif R435 r436 ADC6 with cut.gif
7 R434 r438 ADC7 with cut.gif R435 r436 ADC7 with cut.gif
8 R434 r438 ADC8 with cut.gif R435 r436 ADC8 with cut.gif
10 R434 r438 ADC10 with cut.gif R435 r436 ADC10 with cut.gif
11 R434 r438 ADC11 with cut.gif R435 r436 ADC11 with cut.gif
12 R434 r438 ADC12 with cut.gif R435 r436 ADC12 with cut.gif

Rear Scint Pedestal

Run # Scint Histogram Wire #4 Description
447 R447 ADC15.gif R447 ADC7.gif Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply On, Preamp Power supply at 5.6 V, trigger: gun OR either scintillator
448 R448 ADC15.gif R448 ADC7.gif Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off
449 R449 ADC15.gif R449 ADC7.gif Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off, DC preamp off
450 R450 ADC15.gif R450 ADC7.gif Beam turned off, Pedestal run, Sense wire at 1450 Volts, Translator Power supply Off, DC preamp off, Now just trigger on gun pulse, DC HV off
Observations
The pedestal for the last scintilator is below channel 70. There seems to be a lot of noise around channel 150.
turning the DC amplifier off increases the noise on the line (no more differential amplification).


Go Back