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Fundamental Technologies

Galileo Spacecraft Pages

LEMMS Channel Descriptions

Channel Name	Species	Energy Range (MeV)	Readout Interval^b (in 1/3 s)	Logic
A0	Z ≥ 1	0.022-0.042	1	A1 (A2 B1)
A1	Z ≥ 1	0.042-0.065	1	A2 (A3 B1)
A2	Z ≥ 1	0.065-0.120	2	A3 (A4 B1)
A3	Z ≥ 1	0.120-0.280	2	A4 (A5 B1)
A4	Z ≥ 1	0.280-0.515	2	A5 (A6 B1)
A5	Z ≥ 1	0.515-0.825	2	A6 (A7 B1)
A6	Z ≥ 1	0.825-1.68	2	A7 (A8 B1)
A7	Z ≥ 1	1.68-3.20	2	A8 (A9 B1)
A8	Z ≥ 2	3.50-12.4	4	A9 (B1 C2)
B0	Z = 1	3.20-10.1	4	A7 B1 (C2)
B1	electrons	~1.5-10.5	4	A2 (A4) B1 (B2 C2)
B2	Z = 2	16.0-100	4	A8 B3 (C2)
DC0	Z ≥ 2	14.5-33.5	4	(B1) D2 (C1)
DC1	Z ≥ 2	51-59	4	(B1) C2 D1
DC2	electrons	>~2	4	(B1) D1* (D2)
DC3	electrons	>~11	4	(B1) C1 (C2) D1
E0	electrons	0.015-0.029	1	E11 (E12 E2)
E1	electrons	0.029-0.042	1	E12 (E13 E2)
E2	electrons	0.042-0.055	2	E13 (E14 E2)
E3	electrons	0.055-0.093	2	E14 (E15 E2)
F0^a	electrons	0.093-0.188	2	E15 (E16 E2); F11 (F12 F2)
F1	electrons	0.174-0.304	2	F12 (F13 F2)
F2	electrons	0.304-0.527	2	F13 (F14 F2)
F3	electrons	0.527-0.884	2	F14 (F15 F2)
AS	singles	all counts in detector	8	A1
BS	singles	all counts in detector	4	B1
CS	singles	all counts in detector	4	C1
DS	singles	all counts in detector	4	D1
EB1	background	sidewise penetrators	4	E16 (E2)
EB2	background	E1E2 coincidences	4	E11 E2
FB1	background	sidewise penetrators	4	F15 (F2)
FB2	background	F1F2 coincidences	4	F11 F2

*D1 per telecon McEntire, 4/12/94
^a Channel F0 is the sum of ~100-200 keV events seen in detectors E1 and F1.
^b At nominal 3 RPM: 1/3 s = 60 readouts/spin, 6° 'sectors'; 2/3 s = 30 readouts/spin, 12° 'sectors';
4/3 s = 15 readouts/spin, 24° 'sectors.'

LEMMS PHA is accumulated for 2/3 s every 4.66s. There are 46 linear channels and 1 high-energy channel.
Sequence is: 11 spectra from Det. A (20-290 at 6.4 keV/ch); 1 spectra from Det. E1 (15-190 keV at 4.5 keV/ch); 1 spectra from Det. F1 (80-890 keV at 20.1 keV/ch). This sequence is 60 2/3 s long, and repeats.

Updated 9/13/05, T. Hunt-Ward
tizby@ftecs.com