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

Array parameters April 2008 (09/04-04/05)

After the modifications and tests made in February 2008, LABOCA was let warm up. It was cooled down again on 8th April, and stayed cold until we discovered sensitivity problems in the beginning of May.

Main parameter file: laboca-2008-04.rcp

Individual scans

Scan #Date Parameter fileArray plotIndividual channel maps
9281 2008-04-18T00:05 Mars_9281_Laboca.rcp array_9281.pdf beams_9281.pdf
9555 2008-04-18T23:27 Mars_9555_Laboca.rcp array_9555.pdf beams_9555.pdf
10406 2008-04-21T23:52 Mars_10406_Laboca.rcp array_10406.pdf beams_10406.pdf
12887 2008-05-02T23:15 Mars_12887_Laboca.rcp array_12887.pdf beams_12887.pdf

Notes on individual channels

Channel #Description
101, 103, 106, 110 Strong cross-talk: 101↔106 & 103↔110.
81, 82, 83, 84-91, 92, 93-96, 135, 136, 142, 145, 150, 151, 157-160 Channels located in group 4 / cable M. 82, 83, 85, 86, and 92 are considered bad, the other active channels pick up signal from channel 92 (cross-talk).
6, 179, 184, 201, 205, 207, 218, 228, 309 Bad (noisy or insensitive) channels.
167, 191, 192 Channels that are bad in some of the maps, but not all.
241 No proper signal. Picks up signal from channels 248 (strong) and 296 (weak).

channel_flags-2008-04.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
# 5 channels show strong cross-talk
cross = [ 101, 103, 106, 110, 241 ]
# Bad channels (no or very weak astronomical signal)
bad = [ 6, 82, 83, 85, 86, 92, 179, 184, 201, 205, 207, 218, 228, 309 ]
# Variable channels (sometimes bad, sometimes not)
bad_maybe = [ 167, 191, 192 ]
# Remaining bolometers on cable M / group 4 (affected by cross-talk)
cable_M = [ 81, 84, 89, 90, 91, 93, 94, 96, 136, 159, 160 ]