GjincBeam: Difference between revisions

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     pixelsize: floating point number in arcseconds (no units)
     pixelsize: floating point number in arcseconds (no units)
     diameter: the diameter of the single dish antenna in meters (no units)
     diameter: the diameter of the single dish antenna in meters (no units)
     samplingFactor: the number of sampled points per telescope FWHM  
     xSamplesPerBeam: the number of sampled points per telescope FWHM beam along the X axis
    ySamplesPerBeam: the number of sampled points per telescope FWHM beam along the Y axis
    xSamplingArcsec: if not None, then use this value instead of xSamplesPerBeam
    ySamplingArcsec: if not None, then use this value instead of ySamplesPerBeam


==Example==
==Examples==
<source lang="python">
<source lang="python">
# In CASA
CASA <3>: au.gjincBeam(115.27)
import analysisUtils as au
Theoretical primary beam FWHP = 52.3039 arcsec
au.gjincBeam(115.27)
Sampled every 10.4608 arcsec (5.000000 points per beam)
Expected effective restoring beam = 54.2091 arcsec
  Out[3]: 54.209121599085897
 
CASA <5>: au.gjincBeam(115.27, xSamplingArcsec=10, ySamplingArcsec=15)
Theoretical primary beam FWHP = 52.3039 arcsec
Sampled every 10 arcsec (5.23039 points per beam) in X
Sampled every 15 arcsec (3.48693 points per beam) in Y
Expected effective restoring beam along X = 54.1741 arcsec
Expected effective restoring beam along Y = 54.5878 arcsec
Geometric mean = 54.3805 arcsec
  Out[5]: 54.380521837034024
</source>
</source>

Latest revision as of 18:30, 27 June 2013

Return to Analysis Utilities

This page documents the gjincBeam function of the Python module analysisUtils.

This function calls the gjinc class to compute the effective restoring beam obtained from the casa command sd_imaging when using the GJINC gridding kernel assuming the GJINC specific parameters are left at their default values. It returns the value in arc seconds.


Usage

au.gjincBeam(frequency, pixelsize=10, diameter=12.0, samplingFactor=2.5)

   frequency: floating point number in GHz (no units)
   pixelsize: floating point number in arcseconds (no units)
   diameter: the diameter of the single dish antenna in meters (no units)
   xSamplesPerBeam: the number of sampled points per telescope FWHM beam along the X axis
   ySamplesPerBeam: the number of sampled points per telescope FWHM beam along the Y axis
   xSamplingArcsec: if not None, then use this value instead of xSamplesPerBeam
   ySamplingArcsec: if not None, then use this value instead of ySamplesPerBeam 

Examples

CASA <3>: au.gjincBeam(115.27)
Theoretical primary beam FWHP = 52.3039 arcsec
Sampled every 10.4608 arcsec (5.000000 points per beam)
Expected effective restoring beam = 54.2091 arcsec
  Out[3]: 54.209121599085897

CASA <5>: au.gjincBeam(115.27, xSamplingArcsec=10, ySamplingArcsec=15)
Theoretical primary beam FWHP = 52.3039 arcsec
Sampled every 10 arcsec (5.23039 points per beam) in X
Sampled every 15 arcsec (3.48693 points per beam) in Y
Expected effective restoring beam along X = 54.1741 arcsec
Expected effective restoring beam along Y = 54.5878 arcsec
Geometric mean = 54.3805 arcsec
  Out[5]: 54.380521837034024