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The efficiencies of the 45-m radiotelescope 2007-2008

Effective for period between Dec. 2007 - June 2008 (Measured between Nov. and Dec. 2007)

-------------------------------------------------------------------------------
Receiver  Frequency   HPBW     Aperture    Main beam  Calib.     EL.   comment
            (GHz)   (arcsec)   effic(%)    effic(%)   source
-------------------------------------------------------------------------------
S40          43     38.5+-0.1   57+-3      73+-4     Mars        45-51
                                                     3C454.3     63-68

             49     33.3  0.2   57  3      72  4     Mars        59-68
                                                     3C454.3     55-59

S80          86     18.4  0.1   36  2      42  2     Mars        70-71
                                                     3C454.3     38-41

            110     15.3  0.2   27  2      35  2     Mars        52-59
                                                     3C454.3     28-29

            115     14.8  0.3   20  1      27  2     Mars        72-73
                                                     3C454.3     54-55

S100         86     18.2  0.1   38  2      44  2     Mars        54-58
                                                     3C454.3     29-33

            110     14.9  0.1   31  2      40  2     Mars        70-71
                                                     3C454.3     38-40

            115     14.9  0.1   23  1      32  2     Mars        72-73
                                                     3C454.3     54-56
----------------------------------------------------------------------------

The error of the efficiencies is mainly due to uncertainty of brightness temperature of the planet. The error of the efficiencies and beam sizes corresponds to one sigma.

1. Brightness Temperatures (T_b) of Sources
   • Mars 210 K (assumed based on compiled data by Shibata, 5 % error is also assumed)
   • The brightness temperature of Mars is known to change depending on the distance to the Sun (R). According to Ulich (1981), the approximate formula to obtain effective T_b is T_b(effective) = T_b x (1.524 AU / R)^1/2. The value of R is taken from Japanese Ephemeris.
2. Diameter of the Planet
   • It is taken from Japanese Ephemeris.
3. References
   • Shibata, Internal Memorandum: Brightness temperatures of Venus, Mars, and Saturn (1990)
   • Ulich, Astron. J., 86, 1619 (1981)
   • Japanese Ephemeris, Maritime Safety Agency of Japan (2007)

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