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Cassini MIMI Pages

Fax to E. Kirsch, S. Livi, B. Wilkin, and D. Mitchell, from T. Armstrong, 11/17/92

Program calculation of ion responses for your proposed MIMI 180º end detectors. I can easily adjust the logic, thicknesses, thresholds, etc. Please check that this is what you intended. I may have misread. Let me know what next.

Kirsch Proposal for MIMI 180º End, as of Sept. 29-Oct. 1 Team Meeting at CESR:

ABSORBER NAME Foil D1 D2 D3 Brass C B
ABSORBER THICKNESSES, MICRONS 100.0 300.0 5000.0 300.0 2860.0 500.0 985.0
ABSORBER MATERIAL ALUM. SILICON SILICON SILICON NICKEL SILICON SILICON
THICKNESS VARIATION, MICRONS 0.0 10.0 0.0 10.0 0.0 10.0 10.0
CONICAL HALF ANGLE, DEGREES 22.5 22.5 22.5 22.5 22.5 22.5 22.5
DETECTOR NOISE, MEV 0.0 0.015 0.0  0.015 0.0 0.010 0.010
ELECTRONIC NOISE, MEV 0.0 0.0 0.0 0.0 0.0 0.0 0.0
NUMBER OF THRESHOLDS SET 0.0 5.0 5.0 1.0 0.0 2.0 3.0
THRESHOLD LEVEL NO. MEV    1 0.0 0.025
D11		 0.026
D21		 0.025
D31		 0.0 0.025
C1		 0.100
B1
THRESHOLD LEVEL NO. MEV    2 0.0 0.110
D12		 0.200
D2X		 0.0 0.0 0.200
C2		 1.000
B2
THRESHOLD LEVEL NO. MEV    3 0.0 0.200
D13 		1.900
D22		 0.0 0.0 0.0 10.00
B3
THRESHOLD LEVEL NO. MEV    4 0.0 7.500
D14		 35.00
D23		 0.0 0.0 0.0 0.0
THRESHOLD LEVEL NO. MEV    5 0.0 30.00
D15		 150.0
D24 		0.0 0.0 0.0 0.0
AVERAGE PROJECTED DEPTH, MIC 104.0 311.9 5197.8 311.9 2973.2 519.8 1024.0
EST.RMS VARN.PROJ.DEPTH, MIC 4.1 12.4 206.0 12.4 117.8 20.6 40.6
NET RMS THICKNESS VARN. (MIC) 4.1 15.9 206.0 15.9 117.8 22.9 41.8
LOWER LIMIT THICKNESS (MIC) 99.8 296.0 4991.8 296.0 2855.3 496.9 982.2
UPPER LIMIT THICKNESS (MIC) 108.1 327.8 5403.8 327.8 3091.0 542.7 1065.8

Fax reply from E. Kirsch, 12/9/92

I thank you very much for the program calculations concerning the LEMMS high energy detector. In the meantime I have improved the design and discussed it also with B. Wilken and S. Livi.

Could you please run the program once more for the new logic and the absorber and discriminator thresholds which I have listed separately.

Thank you very much.

LEMMS B-C-D Detectors

1. Electrons and X-rays

D11· D12 · D21 · D2x = e- = 375 - 550 keV
D11· D12 · D2x · D22 = e- = 0.550 - 2.25 MeV
D11· D12 · D22 · D23 · D31= e- = 2.25 - 3.85 MeV
D11· D12 · D21 · D31 · C11 · B11 = 7.5 - 19.65 MeV
D11· D12 · D21 = e-, X = 25 - 200 keV = single rate D11
S = 5 channels

2. Protons and X-rays

D11· D13 · D21 · D22 = 7 - 8.9 MeV    p
D11· D13 · D22 · D23 · D31 = 8.9 - 35 MeV   p
D11· D13 · D31 · C11  = 35 - 60 MeV   p
D11· D13 · D21 · C11 · B11 = 55 - 100 MeV   p
D11· D13 · D21 · D31 · C12 = 55 - 500 MeV   p
D11· D21 · D22 · D31 = X = 25 - 200 keV    X = single rate D21
S = 6 channels

3. a Particles

D13· D14 · D21 · D23 = a = 28 - 63 MeV 
D13· D14 · D23 · D31 = a = 63 - 130 MeV 
D13· D14 · D31 · C11 = a = 130 - 230 MeV 
S = 3 channels

4. Z>= 3-Particles

D14 · D21 · D23   ~=  35 - 70 MeV 
D14 · D21 · D23   ~=  70 - 140 MeV
S = 2 channels

5. Single rates D31, C11

Total: 18 channels

Discriminator Thresholds

D11 = 0.025 MeV D21 = 0.025 MeV D31 = 0.025 MeV
D12 = 0.2 MeV D2x = 0.2 MeV C11 = 0.025 MeV
D13 = 7.5 MeV D22 = 2.0 MeV C12 = 0.25 MeV
D14 = 30 MeV D23 = 35 MeV B11 = 0.025 MeV

Absorber 1 = 100m Al
Absorber 2 = 300m Si     Detector D1
Absorber 3 = 5000m Si     Detector D2
Absorber 4 = 300m Si    Detector D3
Absorber 5 = 3000m brass
Absorber 6 = 500m Si    Detector C1
Absorber 7 = 3000m  Pt
Absorber 8 = 1000m Si    Detector B1

rPt=21.45 g/cm3
rAu=19.32 g/cm
t=3000m     Pt =3000 · (21.45/19.32) Au
                      =3307m Au

100m = 100 x 10-4 cm = 0.01 cm

.3 cm Brass = 2.55 g/cm2 [8.5 g/cm2=r]

Nickel = 8.9 g/cm3
t = 2.55 g/cm2 / 8.9 g/cm3 = .286 cm

Additional Figures

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Updated 6/9/08, T. Hunt-Ward
tizby@ftecs.com
Figure reconstruction by T. Manweiler.