Atacama Pathfinder EXperiment APEX
LABOCA Calibration
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Home > Instrumentation > LABOCA > LABOCA Calibration > Array parameters

Array parameters August 2008 (25/07-08/09)

LABOCA was warm between the 3rd and 22nd of July. It was cooled down afterwards and was operational from July 25th until September 7th, when we decided to warm it up to 77K because of a shortage of liquid Helium.

Main parameter file: laboca-2008-08.rcp

Individual scans

Scan #Date Parameter fileArray plotIndividual channel maps
34178 2008-07-26T07:22 Uranus_34178_Laboca.rcp array_34178.pdf beams_34178.pdf
35710 2008-07-31T05:15 Uranus_35710_Laboca.rcp array_35710.pdf beams_35710.pdf
35797 2008-07-31T22:29 Mars_35797_Laboca.rcp array_35797.pdf beams_35797.pdf
37013 2008-08-06T22:58 Mars_37013_Laboca.rcp array_37013.pdf beams_37013.pdf
37213¹ 2008-08-07T18:12 Mars_37213_Laboca.rcp array_37213.pdf beams_37213.pdf
38771 2008-08-15T05:29 Uranus_38771_Laboca.rcp array_38771.pdf beams_38771.pdf
38903¹ 2008-08-15T18:48 Mars_38903_Laboca.rcp array_38903.pdf beams_38903.pdf
39585 2008-08-19T22:27 Mars_39585_Laboca.rcp array_39585.pdf beams_39585.pdf
39814 2008-08-20T08:26 Uranus_39814_Laboca.rcp array_39814.pdf beams_39814.pdf
 ¹ Scan 37213 and 38903 are not usable because of extreme atmospheric instability. They are just listed here for completeness.

Notes on individual channels

Channel #Description
101, 103, 106, 110 Strong cross-talk: 101↔106 (also noisy) & 103↔110.
81, 82, 83, 84, 85, 86, 89, 90, 91, 92, 93, 94, 96, 136, 159, 160 Active channels located in group 4 / cable M. No signal/noisy or cross-talk with channel 83.
6, 184, 192, 220, 257 Bad channels not showing any astronomical signal.
201, 205, 207, 218, 228, 309 Insensitive channels, showing very low signal levels.
98, 179, 191, 202, 219 Suspicious channels (sometimes bad, sometimes not)
241 No proper signal. Picks up signal from channels 248 (strong) and 296 (weak).

channel_flags-2008-08.boa:

# 25 channels not connected to any bolometer
not_connected = [ 29,  33,  35,  40,  64,  66, 124, 135, 142, 144, 146, 151, 158,
                 189, 193, 195, 200, 224, 226, 284, 295, 302, 304, 306, 311 ]
# 20 channels with 1MOhm resistor
resistor = [  15,  16,  87,  88,  95, 139, 143, 145, 149, 150, 157, 178,
             181, 186, 187, 188, 190, 255, 310, 317 ]
# 2 channels sealed with an absorber
blind = [ 4, 163 ]
sealed = blind
# channels showing strong cross-talk
cross = [ 101, 103, 106, 110, 241 ]
# Bad channels (no astronomical signal, noisy or insensitive)
bad = [ 6, 98, 179, 184, 191, 192, 201, 205, 207, 218, 220, 228, 257, 309 ]
# Suspicious channels (sometimes bad, but usually not - check your data)
bad_maybe = [ 202, 219 ]
# Remaining bolometers on cable M / group 4 (bad and/or cross-talk)
cable_M = [ 81, 82, 83, 84, 85, 86, 89, 90, 91, 92, 93, 94, 96, 136, 159, 160 ]
# Cable_M is considered bad
bad = bad + cable_M