[evlatests] Changing Fluxes for 3C48, 3C138, 3C147

[Rick Perley]

     The '2019 Flux Densities' observation is reduced.  The data were 
taken Jan31/Feb 01 under ideal conditions.  Besides monitoring the 
standard sources, emphasis was on finding southern calibrators.  As 
usual the major goal was uncovering various system issues.  Come to the 
Thursday meeting if you want to learn about these ...

     The 'standard' source 3C48 is known to have undergone a major 
flare, starting a bit more than a year ago.  The effects of this are 
quite obvious in the results.  But I find that both 3C138 and 3C147 have 
also increased, although not by the same factor as 3C48.

     All fluxes are based on 3C286.  As a check, 3C295 compared to 3C286 
-- no change within the errors (less than 1%, except at Q-band).

     Below are the ratios of the current fluxes for 3C48, 3C138 and 
3C147 compared to their 'Perley-Butler' values from 2013.

Note that at P-band, all ratios are 1.00 (to 1%).

     Freq (MHz)    3C48    3C138    3C147

-----------------------------------------------------

     1022             1.00    1.00    1.00

     1465            1.00    1.00    1.00

     1865            1.00    0.99    1.00

     2565             1.01    1.00    1.01

     3565            1.01    1.00    1.01

     4885            1.02    1.02    1.01

     6680            1.03    1.02    1.01

     8435            1.05    1.03    1.02

     11320          1.08    1.05    1.03

     14065          1.12    1.05    1.04

     16564          1.14    1.06    1.04

     19064          1.18    1.07    1.05

     25564          1.25    1.08    1.06

     32064          1.32    1.09    1.08

     37064          1.37    1.09    1.07

     42064          1.42    1.10    1.07

     48064         1.42    1.11    1.03

----------------------------------------------------------

     Accuracies are better than 1%, except at 48064 GHz (likely 3% or so).