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

Array parameters March 2014
(15/03-01/05)

After the technical shutdown during the altiplanic winter, LABOCA was cooled down again and we started with measurements on 15th of March. It was kept cold until mid-May, but only used until the 1st of May.

Main parameter file: laboca-2014-03.rcp

Individual scans

Scan #Date Parameter fileArray plotIndividual channel maps
3507 2014-03-15T04:59 Mars_3507_Laboca.rcp array_3507.pdf beams_3507.pdf
3545 2014-03-15T06:47 Mars_3545_Laboca.rcp array_3545.pdf beams_3545.pdf
3725 2014-03-16T03:35 Mars_3725_Laboca.rcp array_3725.pdf beams_3725.pdf
3760 2014-03-16T05:11 Mars_3760_Laboca.rcp array_3760.pdf beams_3760.pdf
4855 2014-03-20T11:16 Saturn_4855_Laboca.rcp array_4855.pdf beams_4855.pdf
15839 2014-04-22T04:27 Mars_15839_Laboca.rcp array_15839.pdf beams_15839.pdf

Notes on individual channels

Note: Channels which are terminated with a resistor are not listed in the following table.

Compared to last year, channel 257 apparently is recovered (although somewhat noisy). However, the whole group 5 / cable L (close to where the wafer is broken) is now bad (see below), which means we have lost another 20 channels in the northwest corner of the array.

Channel #Description
101, 103, 106, 110 Strong cross-talk: 101↔106 and 103↔110. 101 and 103 may be usable for point sources only.
81, 82, 83, 84, 85, 86, 89, 90, 91, 92, 93, 94, 96, 136, 159, 160 Channels located in group 4 / cable M. These channels usually don't show any astronomical signal and are considered bad.
114, 116, 117, 118, 119, 120, 126, 128, 129, 130, 131, 132, 133, 134, 141, 147, 148, 152, 153, 154, 155, 156 Channels located in group 5 / cable L. These channels don't show astronomical signal (factor 20 below normal) and are considered bad.
177, 179, 180, 182, 183, 184, 185, 191, 192, 201, 202, 203, 205, 207, 217, 218, 220 Channels located in group 7 / cable A. These channels don't show astronomical signal and/or cross-talk and are considered bad.
6, 45, 170, 199, 204, 206, 208, 211, 213, 219, 228, 241, 309 Bad channels, not showing any astronomical signal or very low signal levels, unconnected to groups 4, 5, or 7 above.

channel_flags-2014-03.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 ]
# Bad channels (no/low signal or very high noise)
bad = [ 6,  45,  81,  82,  83,  84,  85,  86,  89,  90,  91,  92,  93,  94,
       96, 114, 116, 117, 118, 119, 120, 126, 128, 129, 130, 131, 132, 133,
      134, 136, 141, 147, 148, 152, 153, 154, 155, 156, 159, 160, 170, 177,
      179, 180, 182, 183, 184, 185, 191, 192, 199, 201, 202, 203, 204, 205,
      206, 207, 208, 211, 213, 217, 218, 219, 220, 228, 241, 309 ]