The efficiencies of the 45-m radiotelescope 2009-2010

Measured between Dec. 2009 and Apr. 2010

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Receiver  Frequency   HPBW     Aperture    Main beam  Calib.     EL.   comment
            (GHz)   (arcsec)   effic(%)    effic(%)   source
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S80          86     18.7+-0.1   37+-2      45+-3     Mars	51-55
                                                     3C273      55-56 
            110     15.3  0.2   26  2      34  2     Mars     	33-36
                                                     3C454.3    57-55
            115     15.9  0.2   19  1      30  2     Mars	40-44
                                                     3C454.3    50-48

S100         86     18.4  0.1	42  2	   49  3     Mars	51-55
                                                     3C273      55-56
            110     15.0  0.2	29  2	   38  2     Mars	33-36
                                                     3C454.3    57-55
            115     14.9  0.2	23  1	   32  2     Mars	40-44
                                                     3C454.3    50-48

T100(H)      86     19.2  0.3	38  2	   49  4     Mars	55-61
                                                     3C273      56
            110     16.5  0.1	26  2	   41  3     Mars 	31-40
                                                     3C273      48-45             
            115     15.6  0.2	25  1	   38  3     Mars	45-42
                                                     3C273      45-42

T100(V)      86     18.9  0.2	38  2	   47  3     Mars	55-61
                                                     3C273      56
            110     15.4  0.2	31  2      42  3     Mars	31-40
                                                     3C273      48-45
            115     14.4  0.2	29  1      38  3     Mars	45-42
                                                     3C273      45-42
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The error of the efficiencies is mainly due to uncertainty of brightness temperature of the planet.

Brightness Temperatures (T_b) of the Source (We used temperatures compiled by Shibata 1990)
Saturn
- 115 GHz 155+-11 K (Interpolation of the values at 2.1 mm and 3.1 mm)
- 110 GHz 153+-11 K (Interpolation of the values at 2.1 mm and 3.1 mm)
- 86 GHz 153+-5 K
Diameter of the Planet
- Diameters of the planet are taken from Japanese Ephemeris. In the case of Saturn, the diameters in the polar and equatorial directions are significantly different. In Japanese Ephemeris, only the radius in the polar direction is listed. Therefore, a correction is done with the ratio (1.12) of the diameters in the two directions.
- The effective diameter is calculated with a formula below:
  2 x (1.12 x polar radius x polar radius)^1/2.
References
- Shibata, Internal Memorandum: Brightness temperatures of Venus, Mars, and Saturn (1990)
- Japanese Ephemeris, Maritime Safety Agency of Japan (2008)

2008-03-13 nro45mrt @ NRO