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LABOCA Calibration
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Array parameters September 2013
(12/09-24/11)

LABOCA was cooled down again on September 11th, and has been used more or less continuously afterwards until the end of the Swedish time block on 24th of November. It was then warmed up for the summer shutdown and will be available again in March 2014.

Main parameter file: laboca-2013-09.rcp

Individual scans

Scan #Date Parameter fileArray plotIndividual channel maps
59258 2013-09-12T05:17 Uranus_59258_Laboca.rcp array_59258.pdf beams_59258.pdf
59588 2013-09-13T04:56 Uranus_59588_Laboca.rcp array_59588.pdf beams_59588.pdf
61012¹ 2013-09-18T03:29 Uranus_61012_Laboca.rcp array_61012.pdf beams_61012.pdf
61026¹ 2013-09-18T04:18 Neptune_61026_Laboca.rcp array_61026.pdf beams_61026.pdf
61237 2013-09-19T04:04 Uranus_61237_Laboca.rcp array_61237.pdf beams_61237.pdf
61527² 2013-09-20T12:13 Mars_61527_Laboca.rcp array_61527.pdf beams_61527.pdf
62470 2013-09-24T04:06 Uranus_62470_Laboca.rcp array_62470.pdf beams_62470.pdf
64129 2013-09-29T12:43 Mars_64129_Laboca.rcp array_64129.pdf beams_64129.pdf
65265 2013-10-02T12:04 Mars_65265_Laboca.rcp array_65265.pdf beams_65265.pdf
74479 2013-10-24T04:17 Uranus_74479_Laboca.rcp array_74479.pdf beams_74479.pdf
75905 2013-10-29T11:26 Mars_75905_Laboca.rcp array_75905.pdf beams_75905.pdf
80814 2013-11-14T01:45 Uranus_80814_Laboca.rcp array_80814.pdf beams_80814.pdf
 ¹ These scans are not considered for the averaged parameter file because of their relatively low S/N.
 ² This scan is not considered for the averaged parameter file because LABOCA warmed up before the map was finished.

Notes on individual channels

Note: Channels which are terminated with a resistor are not listed in the following table anymore.
Also, from 2013 onward channel #241 is listed under "bad channels" and not under "cross-talk", since the cross-talkers may be usable for point sources, while #241 is not usable at all.

Compared to earlier this year, channel 257 is now consistently bad. Also, channel 170 seems to be unusable after about mid-September.

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.
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 are considered bad.
6, 45, 114, 133, 199, 204, 206, 208, 211, 213, 219, 228, 241, 257, 309 Bad channels, not showing any astronomical signal or very low signal levels, unconnected to groups 4 or 7 above.
65, 77, 170 Variable channels. While 65 and 77 are usually usable, 170 is considered bad after mid-September.

channel_flags-2013-09.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, 133, 136, 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, 257, 309 ]