The lband wide receiver was replaced in feb03. The cal values were measured on 6mar03. Data was taken from march through sep03 using the interim correlator. Since the correlator can only measure 4 frequency bands simultaneously, two different frequency groups were used :(1175,1300,1375,1415) and (1415,1550,1610,1666). Gain curves were then computed fitting for gain as a function of za (fits using azimuth terms did not improve the fit enough to make a difference). The fitting function (with za in degrees) is:
g(za)=c0 +c1*za + c2*(za14)^2 +c3*(za14)^3where the ^2 and ^3 terms are only applied for za ge 14 degrees.
The plots show the gain fits vs za with the fit residuals.
freq  # of points  fit rms
K/Jy 





















1415Mhz has twice the measurements for the fits since it was included in both frequency groups. The gain increases from 1175 to 1415 Mhz (this could be real or just an error in the cal measurements). Looking at the lbw system performance, you can see that the SEFD is also increasing as you go to higher frequency. Most of the SEFD increase is from Tsys decreasing but some may be from the cal.
Note: The fits using za and az terms are available for comparison. They are not the curves being used.
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