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The FLUX program

FLUX is a superset of ASTRO which incorporates a new language (called FLUX) to allow the derivation of fluxes from pointings scans made in single-dish or interferometric modes. One has to use the following sequence:

FLUX\FILE filename
    - Define the entry file 'filename' (produced by PRINT FLUX/OUT)     

FLUX\READ antenna frequency 
    - Read the gaussian fits data from the antenna number 
      'antenna' and the frequency 'frequency'. 

ASTRO\SET FLUX name flux  
    - Attribute the flux value 'flux' to the source (usually a quasar)
      'name'. This optional command is used when no planet measurements is 
      available and/or as a redundant flux check on strong and well known 
      quasars.  Note that this is an ASTRO command.

FLUX\SOLVE name1 [name2 [...]]] 
    - Use the planet or quasar 'name1' as flux reference. For a planet,
      the flux is derived using the gain USB/LSB and the frequency 
      informations:
$Flux(planet) = \frac{S(\nu_{lsb})+ g\times
S(\nu_{usb})}{1+g}$ (Jy)
      Then calculate the fluxes of all sources as described below at the 
      ``gain corrected'' frequency:
$\nu_{flux} = \frac{\nu_{lsb}+ g\times \nu_{usb}}{1+g}$ GHz
         + Correct Azimuth subscan for elevation pointing error
         + Correct Elevation subscan for azimuth pointing error
         + Average both subscans to derive the source intensity 
           (with proper weighting using standard deviations)
         + Average all independant scans on the same source (with 
           proper weighting)
         + Determine the  average antenna efficiency from the list 
           of sources of known flux, with error estimate
         + Determine the unknown fluxes, giving two error estimates:
           Relative (only the noise in the source measurement) and 
           Absolute (which also includes the error on antenna efficiency)

FLUX\PRINT /OUTPUT file [New]
    - Print the date and an information line on the meaning of each column,
      then the fluxes with error bars, the frequency, the antenna number
      and the average antenna efficiency (Jy/K), with error bars.
    - The file can be reopened.
 
FLUX\INDEX filei source/OUTPUT fileo [New]
    - Compute the spectral index of the source 'source' from all the
      data available on that source in the input file 'filei' (result from 
      FLUX\PRINT).
    - Write the results on the output file 'fileo'.
    - The output file can be reopened.



Gildas manager 2018-09-24