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Cassini MIMI Investigation at Fundamental Technologies

 

 Historical MIMI Memos and Notes

 

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
Σ = 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
Σ = 6 channels

 

3. α Particles

 

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

 

4. Z>= 3-Particles

 

D14 · D21 · D23   ~=  35 - 70 MeV 
D14 · D21 · D23   ~=  70 - 140 MeV
Σ = 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 = 100μ Al
Absorber 2 = 300μ Si     Detector D1
Absorber 3 = 5000μ Si     Detector D2
Absorber 4 = 300μ Si    Detector D3
Absorber 5 = 3000μ brass
Absorber 6 = 500μ Si    Detector C1
Absorber 7 = 3000μ  Pt
Absorber 8 = 1000μ Si    Detector B1

ρPt=21.45 g/cm3
ρAu=19.32 g/cm
t=3000μ     Pt =3000 · (21.45/19.32) Au
                      =3307μ Au

100μ = 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 8/8/19, Cameron Crane

QUICK FACTS

Manufacturer: The Cassini spacecraft was manufactured by NASA's Jet Propulsion Laboratory, and the Huygens Probe was manufactured by Thales Alenia Space.

Mission Duration: The Cassini-Huygens mission launched on October 15 1997, and ended on September 15 2017.

Destination: Cassini's destination was Saturn and its moons. The destination of the Huygens Probe's was Saturn's moon Titan.

Orbit: Cassini orbited Saturn for 13 years before diving between its rings and colliding with the planet on September 15th, 2017.