Usage of makeSimulatedImage

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Uses simobserve and simanalyze to create a simulated ALMA image of a point source at a specified direction and flux density (in Janskys). See also makePtgfile.

Usage:

au.makeSimulatedImage(phasecenter='J2000 16h25m46.98000s -25d27m38.3300s', 
                 sourcecenter='', flux=1.0, freq=690, field='', pointingspacing=2.0, 
                 configuration='alma.out10.cfg', bandwidth='1GHz', niter=100, 
                 imsize=256, mapsize='', integration='10m', totaltime='200m', 
                 cellsize='auto', threshold='10mJy/beam',
                 shape='point', majoraxis=0, minoraxis=0, positionangle=0,
                 refdate='2012/05/21', hourangle='transit', componentList=None,  
                 writefits=False, normalize=False, verbose=False, analyze=True,
                 ptgfile='', levels=[0.5], weighting='natural', user_pwv='auto', vis=None)
Input parameters:
  • phasecenter: required argument, example: 'J2000 06h00m00.00s -04d00m00.0s'. Colon delimiters are also accepted. J2000 is prepended if missing.
    • can also be specified as 'auto', in which case the position is read from the top line of the ptgfile
  • sourcecenter: if not specified, then assumed to be same as phasecenter
  • flux: floating point flux density of point source (in Jy)
  • freq: floating point frequency (in GHz)
  • field: field name to use for simobserve project directory name
  • configuration: anything in /usr/lib64/casapy/data/alma/simmos/
  • bandwidth: floating point value in GHz
  • imsize: integer value in pixels for simanalyze (image will be square)
  • mapsize: '' or floating point value in arcsec for simobserve (mapped area will be square)
  • totaltime: e.g. '200m' for 200 minutes
  • integration: e.g. '20s' for 200 seconds
  • cellsize: floating point value or 'auto' (use ~5 pixels per beam based on longest baseline of configuration)
  • pointingspacing: units of primary beam, default = 2.0 (i.e. no mosaic)
  • threshold: string value for CLEAN (e.g. '10mJy/beam')
  • shape: 'point' or 'disk'
  • majoraxis: floating point value in arcsec (e.g. 0.90)
  • minoraxis: floating point value in arcsec
  • positionangle: floating value in degrees (e.g. -20)
  • refdate: 'YYYY/MM/DD'
  • hourangle: 'transit' or '-3h'
  • componentList: use the specified component list file instead of phasecenter, shape & size
  • writefits: if True, then also generate FITS images
  • normalize: runs normalizeImage at the end to ensure peak flux of Gaussian
  • analyze: if False, then don't run simanalyze (i.e. only create the ms)
  • ptgfile: if specified, then set setpointing=False and pass this parameter to simobserve
  • levels: contour levels to show in the .flux image (for mosaics)
  • weighting: 'natural' or 'briggs' (simanalyze uses robust=0.5)
  • user_pwv: a value mm or 'auto' to choose ALMA defaults per frequency band
  • vis: if specified and phasecenter=='auto', then use the pointings of all field IDs in the measurement set with the specified field name. If specified and freq=='auto', use the representative frequency. Also use the refdate and configuration of the vis.

Examples:

1. Here is an example that simulates an existing observation of a planet.
au.makeSimulatedImage(vis='uid___A002_Xa56b1d_X174.ms',field='Uranus',integration='30s',totaltime='210s',phasecenter='auto',majoraxis='3.52arcsec',shape='disk')

2.Here is an example that simulates the wrong position used for the phase calibrator 1625-254 in the ALMA Band 9 SV dataset of IRAS16293-2422.
au.makeSimulatedImage(phasecenter='J2000 16h25m46.98000s -25d27m38.3300s', 
                sourcecenter='J2000 16h25m46.891639s -25d27m38.326880s', flux=1.0, freq=690,field='1625')
2012-06-12 18:56:52     WARN    componentlist::close    componentlist closed
Images left in: 1625.makeimage/1625.makeimage.alma.out10.image and 1625.makeimage/1625.makeimage.alma.out10.psf
Pngs left in: 1625.makeimage/1625.makeimage.alma.out10.image.png and 1625.makeimage/1625.makeimage.alma.out10.psf.png

1625.makeimage.alma.out10.image.png
-- ToddHunter - 2012-06-12
Topic revision: r14 - 2015-07-19, ToddHunter
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