Recommended coupling efficiencies for the various GREAT observing cycles
|
Date of flight series |
Source |
θd["] |
ηf |
ηs(l) |
θmb["] |
Notes |
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|
L1 |
L2 <LFA> |
M |
H <HFA> |
L1 |
L2 LFA |
M |
H HFA |
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|
Observing Cycle: Early Science |
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|
Apr 2011 - Nov 2011 |
Mars |
5.1 |
0.95 |
0.55(.03)* |
0.51(.02) |
0.58 |
|
20.12
|
|
|
|
lacking sensitivity to determine Qmb on Mars with L2 |
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|
Jupiter |
46x43 |
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|
Observing Cycle 1: |
re-work of common optics, change of scatter cone (reducing to medium size) |
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|
Apr 2013 - Feb 2014 |
Jupiter |
34x32 |
0.97 |
0.67(.02) |
0.65(.02) |
0.70(.02) |
|
|
|
|
|
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|
Observing Cycle 2: |
|
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|
May 2014 |
Mars |
13.4 |
0.97 |
0.70 0.65 |
0.67 0.69 |
|
0.67(.01) |
19.13 |
14.1 |
11.04 |
6.6 |
first time access to Mars with all channels |
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|
Jan 2015 |
Jupiter |
44x41 |
|
|
|
cold load temperature corrected |
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|
Observing Cycle 3: |
commissioning of upGREAT-LFA (May 2015) |
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|
May 2015 |
Jupiter |
36x34 |
0.97 |
0.64
|
0.69 |
|
0.67 |
|
|
|
|
L1 operated in parallel to LFA, new cc cold load |
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|
Jul 2015 |
Saturn |
16x18 |
|
|
|
relative calibration on Saturn(5) |
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|
Dec 2015 |
Jupiter Mars |
36x34 5.1 |
0.97 |
0.69 |
0.68 |
|
0.69 |
14.8 |
|
6.1 |
configurations: L1/LFA L2/H |
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|
Observing Cycle 4: |
commissioning of upGREAT-HFA (Oct 2016) |
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|
May 2016 |
Jupiter |
39×37 |
0.97 |
0.66 |
<0.65>H <0.65>V |
|
|
19.1 |
14.8 |
|
|
configuration: L1/LFA6 |
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|
Oct 2016 |
Mars |
7.2 |
0.97 |
|
0.69 |
|
<0.63>V |
|
|
14.4 |
|
6.3 |
configuration: HFA/L2 |
||
|
Nov 2016 |
Mars |
7.2 |
0.97 |
0.69 |
<0.65>H <0.65>V |
|
|
|
19.8 |
15.1 |
|
|
configuration: L1/LFA |
||
|
Jan 2017 |
Mars |
5.0 |
0.97 |
0.65 |
<0.65>H <0.63>V |
|
|
|
19.3 |
14.0 |
|
|
configuration: L1/LFA |
||
|
Observing Cycle 5: |
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|
June 2017 |
Jupiter |
40×38 |
0.97 |
|
<0.70>H <0.69>V |
|
|
|
|
|
configuration: LFA/HFA |
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Addendum:
* Uncertainties in brackets describe the variation between measurements (if more than one was performed), not allowing for systematic calibration errors
1. Reference frequencies are 1400 (L1), 1900 (L2), 2500 (M), 4744 (H). Within a given receiver band, beams scale with 1/frequency.
2. Revisiting the Mars data with 2D fits and the Lellouch temperature profile across the planet resulted in a beamwidth of 19.8" (02/15)
3. The narrow beam width of L1 and L2 reflects a rather shallow illumination pattern on the subreflector (~10 dB).
4. The M-channel has not been measured, we interpolate to 11.0"
5. During the NZ deployment neither Mars nor Jupiter was visible. Relative calibration on Saturn showed that couplings have not changed since early 2015.
6. Efficiencies quoted for the array is the average from all pixels, per polarization (H,V). The beam width was determined on the central pixel.