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(Note that the following text is purposely restated.)

LEMMS 180º End Design Criteria (as agreed by Engineering Team Meeting)
(Tom Armstrong, 6/1/93)

  1. Optimize for clean coverage of proton spectrum from ~1 to >20 MeV.
  2. Obtain several electron channels, 1 - 10 MeV.
  3. Assume 100 ns time constants (pulse widths).
  4. Accept incidental x-ray responses to obtain (at least) upper limit fluxes.
  5. Specific, refined and optimized design parameters are needed ASAP.
  6. Weight and power constraints may dictate less complexity.
  7. Use ion implant detectors of least variety (in areas and thicknesses) possible (700 m).
  8. Consider reducing D1 from 300 m to 100 m to reduce sensitivity to electrons.
  9. Consider reducing foil thickness from 100 m (A1 equivalent) to lower proton threshold to ~1 MeV.

Figure 1

Figure 2. Detection probability for x-rays

Summary of LEMMS Measurement Characteristics

Detectors Energy range
(MeV/nuc)		 Nuclear
charge
range		 Number of
energy intervals
measured		 Geometric
factor
(cm2  sr)		 Angular
distribution
(samples per
rotation)		 Dynamic range
(cm-2 sr-1 sec-1)
LEMMS A,B,C 0.020-3.4 z>=1 8 0.02 8, 16 >=1-(10)8
  3.4-10.5 z=1 1 0.02 8 0.5-5(10)7
  0.85-3.1 (He) z>=2 1 0.02 8 >=1-5(10)7
  3.1-62.5 (He) z=2 1 0.02 8 0.5-5(10)7
  1.5-10.5 Electrons 1 0.02 8 0.5-5(10)7
E1, E2 0.015-0.200 Electrons 4 0.03 8, 16 <=1.5-5(10)7
F1, F2 0.100-1.0 Electrons 4 0.015 8, 16 <=5-106
C,D >2 Electrons 1 0.5 8 <1-5(10)6
  >11 Electrons 1 0.5 8 <1-5(10)6
  15.5-130 z>=1 3 0.5 8 <0.1-5(10)6

 

Figure 3. Saturnian x-ray spectra computed for observation distances of 10 RS and 50 RS.

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Updated 6/10/08, T. Hunt-Ward
tizby@ftecs.com
Figure reconstruction by T. Manweiler.