Recommended coupling efficiencies for the various GREAT observing cycles

Date of flight series

Source

θd["]

ηf

ηs(l)

θmb["]

  Notes

L1

L2

<LFA>

M

H

<HFA>

L1

L2

LFA

M

H

HFA

Observing Cycle: Early Science

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

Jupiter

46x43

Observing Cycle 1:

re-work of common optics, change of scatter cone (reducing to medium size)

Apr 2013 - Feb 2014

Jupiter

34x32

0.97

 0.67(.02) 

 0.65(.02) 

 0.70(.02) 

 

 

 

 

 

Observing Cycle 2:

 

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 

Jan 2015

Jupiter

44x41

 

 

 

cold load temperature corrected 

Observing Cycle 3:

commissioning of upGREAT-LFA (May 2015)

May 2015

Jupiter

36x34

 0.97 

0.64

 

  

 0.69 

 

 

 0.67 

 

 

 

 

L1 operated in parallel to LFA, new cc cold load

Jul 2015

Saturn

16x18

 

 

 

relative calibration on Saturn(5)

Dec 2015

Jupiter

Mars

36x34

5.1

0.97

0.69

 

 0.68 

 

 

0.69

 

14.8

 

 

6.1

configurations: L1/LFA

                        L2/H

Observing Cycle 4:

commissioning of upGREAT-HFA (Oct 2016)

May 2016

Jupiter   

39×37

0.97

0.66

<0.65>H

<0.65>V

 

 

19.1

14.8

 

 

configuration: L1/LFA6

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:

June 2017

Jupiter   

40×38

0.97

 

<0.70>H

<0.69>V

 

 

 

 

 

configuration: LFA/HFA

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.

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