Proton Calorimetry/Experimental Runs/2016/Aug2-3: Difference between revisions

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=== LeCroy scope data ===
=== LeCroy scope data ===
Pulse parameters:
* ~500 mV
*Threshold of ~.77 mV.
*Note: Slight reflection seen at ~350 ns after main pulse, which is equivalent to ~10 m (given that the speed of light in a cable is ~4 ns/m).


== Day 2 (August 3rd) ==
== Day 2 (August 3rd) ==


Scope 2: LeCroy HDO6104 [http://teledynelecroy.com/oscilloscope/oscilloscopemodel.aspx?modelid=7170&capid=102&mid=504], Datasheet {{PDFlink | [http://cdn.teledynelecroy.com/files/pdf/hdo6000_oscilloscope_datasheet.pdf ] |1.4 MB}}
Scope 2: LeCroy HDO6104 [http://teledynelecroy.com/oscilloscope/oscilloscopemodel.aspx?modelid=7170&capid=102&mid=504], Datasheet {{PDFlink | [http://cdn.teledynelecroy.com/files/pdf/hdo6000_oscilloscope_datasheet.pdf ] |1.4 MB}}

Revision as of 19:14, 17 August 2016

Dose calibration at Clatterbridge: 0.9 Gy per monitor unit (MU) at 60 MeV.

Day 1 (August 2nd)

Wheel calibration

  • Wheel segments are each ~4 mm.
  • Distance between collimator exit (downstream face of collimator) and the start of the wheel (the upstream face) is 37.5 mm.
  • Distance between the black box edge and upstream edge of the wheel is 41 mm.

Electronic equipment setup:

  • DC offset: -30 mV
  • Record length: 456 ns
  • Threshold: 40 LSB
  • Trigger: 194 mV
  • Gate offset: 10 ns
  • Pre-trigger: 50 ns
  • Charge sensitivity: 20 fc/LSB
High voltage
(V)		 Trigger Rate & additional information Collimator size & beam information Wheel step position Data recorded Run number Comments
-900 ST

Beam off:

  • I: 150.51 μ

Beam on:

  • Rate: 300 kHz on startup.
  • Rate: 25 kHz at -100 mV.
 1.98 mm

Beam startup:

  • Arc current: 750 mV
  • Gas source: 0.67 cc/min

Beam settings change:

  • Arc current: 50 μ
  • Gas source: 0.39 cc/min
  • Dose rate: 0.1 MU/min
 N/A [startup] Beam startup and calibration
-900 ST 0 ADC 01 ~7,000 events in peak
-900 ST 0 waveforms 03 ~7,000 events in peak
-900 ST 20 ADC 05 ~7,000 events in peak
-900 ST 40 ADC 06 ~7,000 events in peak
-900 ST 60 ADC 07 ~7,000 events in peak
-900 ST 80 ADC 08 ~7,000 events in peak
-900 ST 100 ADC 09 ~7,000 events in peak
-900 ST 100 waveforms
(~0.5 GB)		 11 Beam dropped. Repeat in Run 13.
-900 ST 100 waveforms
(~1 GB)		 13 Repeat of Run 10.
-900 ST 120 ADC 14 ~7,000 events in peak
-900 ST 140 ADC 15 ~7,000 events in peak
-900 ST 160 ADC 16 ~6,000 events in peak
-900 ST 130 ADC 17 ~7,000 events in peak
-900 ST 150 ADC 18 ~6,000 events in peak
-900 ST 165 (Just before Bragg peak, which is at wheel step 166.) ADC 19 ~6,000 events in peak.
-900 ST 170 ADC 20 Beam dropped. ~4,000 events in peak. Repeat in Run 21.
-900 ST 170 ADC 21 Repeat of Run 20. ~4,000 events in peak.
-900 ST 173 (Bragg peak fall-off area.) ADC 22 Beam dropped. Repeat in Run 23.
-900 ST 173 ADC 23 Repeat of Run 22. ~1.800 events in peak
-900 ST 175 ADC 24
-900 ST 179 ADC 25 ~30 events in peak. No "peak" apparent; potentially only secondaries.
-900 ST 167 (Tip of Bragg peak.) ADC 26 ~7,000 events in peak.
-900 ST Rate: 25 kHz (1,000 events in 45 ms) 0 ADC 27 ~7,000 events in peak. Back to starting point on calibration wheel to compare with Run 01.
BEAM OFF.
Integrated dose: Dose A: 36.7 MU. Dose B: 36.6 MU.
Total beam time run: 99 min.
-900 ST 0 ADC 28 Background run. Acquisition left over lunch. ~140 events in peak.


[LUNCH] - approx. 1 hr.


PMMA modulator block cross-check

PMMA modulator blocks of thickness equivalent to particular steps of calibration wheel inserted into beamline at location of wheel (just downstream of nozzle) and upstream inside modulator box to cross-check against data obtained earlier using calibration wheel.

High voltage
(V)		 Trigger Rate & additional information Collimator size & beam information PMMA thickness
(mm)		 Position of PMMA block Data recorded Run number Comments
BEAM ON.
Dose monitor operation reset.
-900 ST Rate: 20 kHz Threshold: 40 LSB 0 (No PMMA. Calibration wheel removed.) N/A ADC 29 ~7,000 events in peak
-900 ST 0 N/A waveforms
(~1.2 GB)		 31
-900 ST Rate: ~25 kHz 7.24 mm (corresponding to wheel step 40; 8.3 mm water) Same position the calibration wheel was. ADC 32 ~7,000 events in peak
-900 ST 7.24 mm Same position the calibration wheel was. waveforms
(~1 GB)		 34
-900 ST Rate: ~12 kHz 7.24 mm Upsteam in usual position inside modulator box. ADC 35 ~7,000 events in peak. Beam misbehaviour (shifting) starting with this run and onwards.
-900 ST 7.24 mm Upsteam in usual position inside modulator box. waveforms
(~1.1 GB)		 36
-900 ST ADC: ~4373
After beam shift
Rate: ~20 kHz		 13.4 mm (corresponding to wheel step 80; 15.6 mm water) Same position the calibration wheel was. ADC 37 ~7,000 events in peak
-900 ST 13.4 mm Same position the calibration wheel was. waveforms
(~1 GB)		 38
-900 ST Rate: ~7 kHz
ADC: ~4900
After beam shift		 13.4 mm Upsteam in usual position inside modulator box. ADC 39 ~5,000 events in peak
-900 ST 13.4 mm Upsteam in usual position inside modulator box. waveforms
(~1 GB)		 40
BEAM OFF.
Integrated dose: Dose A: 6.7 MU. Dose B: 6.9 MU.
Total beam time run: 94.19 min.


Rate tests

All PMMA absorbers removed from beam. 1.98 mm collimator still in place.

High voltage
(V)		 Trigger Rate & additional information Collimator size & beam information Data recorded Run number Comments
BEAM ON.
Dose monitor operation reset.
-900 ST Rate: 20 kHz
Foil current: 0.005 nA
Arc current: 50 μA		 ADC 41 ~7,000 events in peak. No absorbers in beam.
-900 ST waveforms
(~1 GB)		 42
-900 ST Rate: 50 kHz
Foil current: 0.0125 nA
Arc current: 75 μA		 ADC 43 ~7,000 events in peak. Increased arc current to up the rate.
-900 ST waveforms
(~1 GB)		 44
-900 ST Dose rate: 0.4 - 0.5.
Before rate drop
  • Rate: 85 kHz
  • Foil current: 0.0250 nA
  • Arc current: 150;μA
  • I: 150.5;μA

After rate drop

  • Rate: 90 kHz
  • Foil current: 0.0300 nA
  • Arc current: 200;μA
 ADC 45 ~10,000 events in peak.
-900 ST waveforms
(~1.6 GB)		 46
-900 ST Rate: 140 kHz
Foil current: 0.0500 nA
Arc current: 400 μA		 ADC 47 ~15,000 events in peak. Increased arc current to up the rate.
-900 ST Foil current: Dropped from ~0.0450 nA to 0.0370 nA waveforms
(~1.6 GB)		 48
-900 ST Rate: 250 kHz
Foil current: Dropped from 0.1080 nA to 0.1050 nA
Arc current: 800 μA
I: 151.3 μA		 ADC 49 ~15,000 events in peak. Increased arc current to up the rate.
-900 ST Foil current and rate went down over time. Arc current down to 700 μA waveforms
(~2 GB)		 50
-900 ST Rate: 300 kHz (scope)
Foil current: 0.25-0.27 nA --> 500 kHz (extrapolated)
I: 170.5 μA
Arc current: 1.2 mA		 ADC 51 ~300 events in peak. Pile-up seen in ADC spectrum.
-900 ST Foil current: 0.20-0.27 nA
I: 171.2 μA		 waveforms
(~2 GB)		 53
BEAM OFF.
Integrated dose: Dose A: 134.7 MU. Dose B: 134.2 MU.
Total beam time run: 92.22 min.

LeCroy scope data

Pulse parameters:

  • ~500 mV
  • Threshold of ~.77 mV.
  • Note: Slight reflection seen at ~350 ns after main pulse, which is equivalent to ~10 m (given that the speed of light in a cable is ~4 ns/m).

Day 2 (August 3rd)

Scope 2: LeCroy HDO6104 [1], Datasheet Template:PDFlink

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