Fluxscale: Difference between revisions
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Created page with '== Help on fluxscale task: == <pre> Bootstrap the flux density scale from standard calibrators After running gaincal on standard flux density calibrators (with or …' |
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Revision as of 20:43, 16 March 2012
Help on fluxscale task:
Bootstrap the flux density scale from standard calibrators After running gaincal on standard flux density calibrators (with or without a model), and other calibrators with unknown flux densities, fluxscale will determine the flux density of the unknowns calibrators that are most consistent with the standard calibrator antenna gains. Check the log output to make sure that reasonable flux densities are obtained. Keyword arguments: vis -- Name of input visibility file default: none; example: vis='ngc5921.ms' caltable -- Name of input calibration table default: none; example: caltable='ngc5921.gcal' This cal table was obtained from task gaincal. fluxtable -- Name of output, flux-scaled calibration table default: none; example: fluxtable='ngc5921.gcal2' The gains in this table have been adjusted by the derived flux density each calibrator. The MODEL_DATA column has NOT been updated for the flux density of the calibrator. Use setjy to do this if it is a point source. reference -- Reference field name(s) The names of the fields with a known flux densities or visibilties that have been placed in the MODEL column by setjy or ft for a model not in the CASA system. The syntax is similar to field. Hence field index or names can be used. default: none; example: reference='1328+307' transfer -- Transfer field name(s) The names of the fields with unknown flux densities. These should be point-like calibrator sources The syntax is similar to field. Hence source index or names can be used. default: '' = all sources in caltable that are not specified as reference sources. Do not include unknown target sources example: transfer='1445+099, 3C84'; transfer = '0,4' NOTE: All fields in reference and transfer must have solutions in the caltable. append -- Append fluxscaled solutions to the fluxtable. default: False; (will overwrite if already existing) example: append=True refspwmap -- Vector of spectral windows enablings scaling across spectral windows Keyword arguments: vis -- Name of input visibility file default: none; example: vis='ngc5921.ms' caltable -- Name of input calibration table default: none; example: caltable='ngc5921.gcal' This cal table was obtained from task gaincal. fluxtable -- Name of output, flux-scaled calibration table default: none; example: fluxtable='ngc5921.gcal2' The gains in this table have been adjusted by the derived flux density each calibrator. The MODEL_DATA column has NOT been updated for the flux density of the calibrator. Use setjy to do this if it is a point source. reference -- Reference field name(s) The names of the fields with a known flux densities or visibilties that have been placed in the MODEL column by setjy or ft for a model not in the CASA system. The syntax is similar to field. Hence field index or names can be used. default: none; example: reference='1328+307' transfer -- Transfer field name(s) The names of the fields with unknown flux densities. These should be point-like calibrator sources The syntax is similar to field. Hence source index or names can be used. default: '' = all sources in caltable that are not specified as reference sources. Do not include unknown target sources example: transfer='1445+099, 3C84'; transfer = '0,4' NOTE: All fields in reference and transfer must have solutions in the caltable. append -- Append fluxscaled solutions to the fluxtable. default: False; (will overwrite if already existing) example: append=True refspwmap -- Vector of spectral windows enablings scaling across spectral windows default: [-1]==> none. Example with 4 spectral windows: if the reference fields were observed only in spw=1 & 3, and the transfer fields were observed in all 4 spws (0,1,2,3), specify refspwmap=[1,1,3,3]. This will ensure that transfer fields observed in spws 0,1,2,3 will be referenced to reference field solutions only in spw 1 or 3.