Optimal Value |
Range |
Instrument value |
Instrument value |
Instrument value | |||||||||||||||||||
Instrument name: | MIRAC2 |
OSCIR |
MIRLIN | ||||||||||||||||||||
P.I. of instrument | W. Hoffmann |
C. Telesco |
M. Ressler | ||||||||||||||||||||
Focal ratio | f/40 |
f/36 or f/45 |
f/35 or longer | ||||||||||||||||||||
Expected exit pupil position (in front of focal plane) | 19.14 m |
8.8 m |
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Position of focal plane with respect to mounting surface | 162 mm |
123-273 mm |
~25 mm |
280 mm |
95 mm | ||||||||||||||||||
Field of view | <= 174" |
12" |
9" x 9" |
17" | |||||||||||||||||||
Mass | <= 1000 kg |
~35 kg |
80 kg |
45 kg | |||||||||||||||||||
Bending moment | <= 470 kg m |
~10 kg m |
75 kg m |
? | |||||||||||||||||||
Rotational moment | <= 7900 kg m^2 |
? |
150 kg m^2 |
? | |||||||||||||||||||
Out-of-balance moment | <= 12 kg m^2/s^2 |
? |
will counterweight to minimize |
will counterweight to minimize | |||||||||||||||||||
Maximum diameter | <= 1.75 m |
~0.8 m |
1.3 m |
0.72 m | |||||||||||||||||||
Maximum length | <= 1.0 m |
~0.8 m |
0.6 m |
0.69 m | |||||||||||||||||||
Required cabling through telescope cable wrap:
| |||||||||||||||||||||||
Cable length through wrap | 100 m |
OK |
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Dimensions of electronics rack on telescope | 10x10x20 cm |
25x25x110 cm |
60x40x40 cm | ||||||||||||||||||||
Length of cable between instrument and nearby electronics rack | 5 m |
<= 1.8 m |
1.2 m | ||||||||||||||||||||
Computer interface | ethernet (thinnet) or serial |
ethernet and/or serial |
Ethernet and serial |
Ethernet | |||||||||||||||||||
Cooling requirements: glycol | 4.9 l/min |
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LN2 | ... |
12 + 4 l/day |
yes |
30 l + 5 l/day | |||||||||||||||||||
LHe | ... |
12 + 6 l/day |
yes |
20 l + 10 l/day | |||||||||||||||||||
Electrical power requirements (commercial and clean) | <= 1 kW |
standard (UPS) |
<= 1 kW | ||||||||||||||||||||
Chopping requirements (for proposal) | 2" @ 10 Hz |
<= 32" |
5" @ 5 Hz |
20" @ 5 Hz |
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Mounting hole pattern #1: dia. of bolt pattern = 18 in (457.2 mm), 1/2-13 bolts, 7 locations at ± (15°, 60°, 120°, 180°) from vertical |
... |
std IRTF |
either |
OK | |||||||||||||||||||
Mounting hole pattern #2: dia. of bolt pattern = 24 in (610 mm), 3/8-16 bolts, 12 locations at ±(15°, 45°, 75°, 105°, 135°, 165°) from vertical |
preferred (allows more rotational freedom when mounting) | ... |