pmt calibration / greenhouses bryan musolf. pmt calibration
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PMT Calibration / Greenhouses
Bryan Musolf
PMT Calibration
7/31/11 Bryan Musolf - Fermilab 3
Goals
• Transform raw data into graphs for 30 PMTs
• Observe how the gain and # of photoelectrons (PE) change as a LED intensity changes
• Observe how the gain and # of PE change as high voltage changes
• Find the stable region of each PMT by analyzing the noise
• Extrapolate PMT data
• Ensure the linearity of each PMT
• Further test the PMTs
7/31/11 Bryan Musolf - Fermilab 4
LED intensity• Increasing the LED intensity while keeping the high voltage constant
PE vs. Bias Voltage
0
20
40
60
80
100
120
140
160
180
6 8 10 12 14 16 18 20
Bias Voltage (V)
PE
PE (1000V)
PE (1100V)
PE (1200V)
Gain vs. Bias Voltage
0
2
4
6
8
10
12
14
6 8 10 12 14 16 18 20
Bias Voltage (V)
Gain (E7)
Gain (1000V)
Gain (1100V)
Gain (1200V)
As the PMTs become saturated the PE cannot be measured accurately
As the PE cannot be measured the gain is no longer constant
7/31/11 Bryan Musolf - Fermilab 5
High Voltage• Increasing the high voltage while keeping the LED intensity constant
Noise / Gain / Spec Gain vs. High Voltage
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
900 1100 1300 1500 1700
High Voltage (V)
Noise / Gain / Spec Gain
Gain
Spec Gain
PE vs. High Voltage
0
0.5
1
1.5
2
2.5
900 1000 1100 1200 1300 1400 1500 1600 1700 1800
High Voltage (V)
PE PE
Comparing the experimental gain vs. the specification gain from the company
Approximately1 PE should be hitting the PMT for these tests. This plot ensured that.
7/31/11 Bryan Musolf - Fermilab 6
Noise counts / min and Extrapolation• We then added the noise counts / min to find the stable region of each
PMT• We also extrapolated the data to find the high voltage that would give
us a gain of 5E7Noise / Gain / Spec Gain vs. High Voltage
1000
10000
100000
1E+06
1E+07
1E+08
1E+09
1E+10
1E+11
900 1100 1300 1500 1700
High Voltage (V)
Noise / Gain / Spec Gain
Noise counts / Min
Gain
Spec Gain
Extrapolation
Our gain of 5E7 is right in the stable region of the PMT
7/31/11 Bryan Musolf - Fermilab 7
All 30 PMT• Spec gain vs. high voltage and gain vs. high voltage for all 30 PMT
Gain vs. High Voltage for all 30 PMT
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
900 1000 1100 1200 1300 1400 1500 1600 1700 1800
High Voltage (V)
Gain
PMT01
PMT02
PMT03
PMT04
PMT05
PMT06
PMT07
PMT08
PMT09
PMT10
PMT11
PMT12
PMT13
PMT14
PMT15
PMT16
PMT17
PMT18
PMT19
PMT20
PMT21
PMT22
PMT23
PMT24
PMT25
PMT26
PMT27
PMT28
PMT29
PMT30
Spec Gain vs. High Voltage for all 30 PMT
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
900 1000 1100 1200 1300 1400 1500 1600 1700 1800
High Voltage
Spec Gain
PMT01
PMT02
PMT03
PMT04
PMT05
PMT06
PMT07
PMT08
PMT09
PMT10
PMT11
PMT12
PMT13
PMT14
PMT15
PMT16
PMT17
PMT18
PMT19
PMT20
PMT21
PMT22
PMT23
PMT24
PMT25
PMT26
PMT27
PMT28
PMT29
PMT 30
Our measured gain closely reflects the spec gain given to us by the company
Gain plot starts to break down when PMTs start to become saturated
7/31/11 Bryan Musolf - Fermilab 8
All 30 PMT• Noise vs. high voltage and the extrapolation for all 30 PMT
Noise / min vs. High Voltage for all 30 PMT
100
1000
10000
100000
1000000
10000000
100000000
900 1100 1300 1500 1700
High Voltage (V)
Noise Counts / min
PMT01PMT02PMT03PMT04PMT05PMT06PMT07PMT08PMT09PMT10PMT11PMT12PMT13PMT14PMT15PMT16PMT17PMT18PMT19PMT20PMT21PMT22PMT23PMT24PMT25PMT26PMT27PMT28PMT29PMT30
Extrapolation vs. High Voltage
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
1.00E+11
1.00E+12
900 1000 1100 1200 1300 1400 1500 1600 1700 1800
High Voltage
Extrapolation
PMT01
PMT02
PMT03
PMT04
PMT05
PMT06
PMT07
PMT08
PMT09
PMT10
PMT11
PMT12
PMT13
PMT14
PMT15
PMT16
PMT17
PMT18
PMT19
PMT20
PMT21
PMT22
PMT23
PMT24
PMT25
PMT26
PMT27
PMT28
PMT29
PMT30
We have some very nice PMTs!!
The extrapolation data will allow us to set high voltages to get specific gains
7/31/11 Bryan Musolf - Fermilab 9
All 30 PMT• Gain / Spec gain / Noise layered
Gain / Spec Gain / Noise vs. High Voltage
1.00E+03
1.00E+04
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
1.00E+11
900 1000 1100 1200 1300 1400 1500 1600 1700 1800High Voltage (V)
Gain / Spec Gain / Noise
Gain01 Gain02
Gain03 Gain04
Gain05 Gain06
Gain07 Gain08
Gain09 Gain10
Gain11 Gain12
Gain13 Gain14
Gain15 Gain16
Gain17 Gain18
Gain19 Gain20
Gain21 Gain22
Gain23 Gain24
Gain25 Gain26
Gain27 Gain28
Gain29 Gain30
Spec01 Spec02
Spec03 Spec04
Spec05 Spec06
Spec07 Spec08
Spec09 Spec10
Spec11 Spec12
Spec13 Spec14
Spec15 Spec16Spec17 Spec18
Spec19 Spec20
Spec21 Spec22
Spec23 Spec24
Spec25 Spec26
Spec27 Spec28
Spec29 Spec30
Noise01 Noise02
Noise03 Noise04
Noise05 Noise06
Noise07 Noise08
Noise09 Noise10
Noise11 Noise12
Noise13 Noise14
Noise15 Noise16
Noise17 Noise18
Noise19 Noise20
Noise21 Noise22
Noise23 Noise24
Noise25 Noise26
Noise27 Noise28
Noise29 Noise30
7/31/11 Bryan Musolf - Fermilab 10
Further testing• We found that some of the PMT bases were broken and
needed to be repaired
• In particular, R1 seemed to be the problem on most
7/31/11 Bryan Musolf - Fermilab 11
Further Testing• After fixing the bases we needed to make sure the PMT
bases could withstand the LAr we would be using them in
7/31/11 Bryan Musolf - Fermilab 12
Further Testing• We also needed to make some splitters so we could
connect the PMTs to a high voltage source and an oscilloscope to take measurements
Needless to say, I got a little bit more efficient!
7/31/11 Bryan Musolf - Fermilab 13
Further Testing
• We ran one test in liquid nitrogen
• Everything held up and we got a nice signal
• Testing in liquid nitrogen or LAr will be ready soon
Greenhouses
7/31/11 Bryan Musolf - Fermilab 15
The idea• Our thought is to coat greenhouses with a
scintillator called bis-MSB to shift the ultraviolet light into blue light
• This blue light should help the plants produce “chlorophyll a” which is used in oxygenic photosynthesis
• We need to make sure the bis-MSB will not affect transmittance and will effectively absorb UV light and emit blue light
• My plots will be illustrating the absorption / emittance of the different greenhouse lids
7/31/11 Bryan Musolf - Fermilab 16
Emission pre growing• We used a control, 3% bis-MSB, and 0.3% bis-MSB
• We tested 3 different absorption wavelengthsEmission pre growing (300nm)
0
200
400
600
800
1000
1200
1400
1600
200 300 400 500
Wavelength
Intensity
3%
0.30%
Control
Emission pre growing (350nm)
0
200
400
600
800
1000
1200
1400
1600
200 250 300 350 400 450 500 550
Wavelength
Intensity
3%
0.30%
Control
Emission pre growing (400nm)
0
2000
4000
6000
8000
10000
12000
200 300 400 500
Wavelength
Intensity
3%
0.30%
Control3
As expected, an absorption of 350nm has the most efficient emittance of blue light
Oddly enough, a lower concentration (0.3%) has a more efficient emittance to blue light
7/31/11 Bryan Musolf - Fermilab 17
Emission post growing• After approximately 5 weeks of growing we retested the absorption /
emittance of the three lids again
• We used the same three wavelengthsEmission post growing (300nm)
0
500
1000
1500
2000
2500
3000
200 300 400 500
Wavelength
Intensity
3%
0.30%
Control
Emission post growing (350nm)
0
500
1000
1500
2000
2500
3000
200 250 300 350 400 450 500 550
Wavelength
Intensity
3%
0.30%
Control
Emission post growing (400nm)
0
2000
4000
6000
8000
10000
12000
200 300 400 500
Wavelength
Intensity
3%
0.30%
Control
It seems as if our bis-MSB has been destroyed!
7/31/11 Bryan Musolf - Fermilab 18
Finding the problem• Our next idea is to find out what / when the bis-MSB gets destroyed
• Our idea is to expose three samples to the outside elements and compare their emission / absorption spectrum to three samples that have remained unexposed
Initial emission of outside and inside samples (300nm)
-200
0
200
400
600
800
1000
1200
200 300 400 500
Wavelength
Intensity
Outside sample (3%)
Outside sample (0.3%)
Outside sample(Control)
Inside sample (3%)
Inside sample (0.3%)
Inside sample(Control)
7/31/11 Bryan Musolf - Fermilab 19
Finding the problem• We will be taking the emission / absorption spectrum of the samples
each day to find when the samples lost the bis-MSB or possibly what may have destroyed the bis-MSB
Initial emmision of outside and inside samples (350nm)
0
1000
2000
3000
4000
5000
6000
200 300 400 500
Wavelength
Intensity
Ouside Sample (3%)
Outside sample (0.3%)
Ouside sample (Control)
Inside sample (3%)
Inside sample (0.3%)
Inside sample (Control)
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