; TRUEP ;--------------------------------------------------------------- ;! determines true antenna polarization from special data sets ;# Task UV Polarization Calibration ;----------------------------------------------------------------------- ;; Copyright (C) 2010-2011 ;; Associated Universities, Inc. Washington DC, USA. ;; ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2 of ;; the License, or (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public ;; License along with this program; if not, write to the Free ;; Software Foundation, Inc., 675 Massachusetts Ave, Cambridge, ;; MA 02139, USA. ;; ;; Correspondence concerning AIPS should be addressed as follows: ;; Internet email: aipsmail@nrao.edu. ;; Postal address: AIPS Project Office ;; National Radio Astronomy Observatory ;; 520 Edgemont Road ;; Charlottesville, VA 22903-2475 USA ;----------------------------------------------------------------------- TRUEP LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC TRUEP: determines true antenna polarization from special data INNAME Normal UV file name (name) INCLASS Normal UV file name (class) INSEQ 0.0 9999.0 Normal UV file name (seq. #) INDISK 0.0 9.0 Normal UV file disk unit # IN2NAME Rotated UV file name IN2CLASS Rotated UV file class IN2SEQ 0.0 9999.0 Rotated UV file seq. # IN2DISK 0.0 9.0 Rotated UV file disk # SOURCES Source name: (1) first file (2) second file, rest ignored QUAL -10.0 Calibrator qualifier -1=>all CALCODE Calibrator code ' '=>all TIMERANG Time range to use SELBAND Bandwidth to select (kHz) SELFREQ Frequency to select (MHz) FREQID Freq. ID to select. SUBARRAY 0.0 1000.0 Sub-array, 0=>all BIF Low IF number to do EIF Highest IF number to do BCHAN 0.0 First channel included ECHAN 0.0 last channel included DOCALIB -1.0 101.0 > 0 calibrate data & weights > 99 do NOT calibrate weights GAINUSE CL (or SN) table to apply DOPOL -1.0 10.0 If >0.5 correct polarization. PDVER PD table to apply (DOPOL>0) BLVER BL table to apply. FLAGVER Flag table version DOBAND -1.0 10.0 If >0.5 apply bandpass cal. Method used depends on value of DOBAND (see HELP file). BPVER Bandpass table version SMOOTH Smoothing function. See HELP SMOOTH for details. SPECTRAL -1.0 1.0 > 0 => do a channel-dependent solution APARM (1) antenna that rotates (2) rotation angle 0 -> 90 (3) = 1 -> display avg data (ignored if SPECTRAL > 0) (4) Freq smoothing type: 0 no (5) Smoothing diameter (6) Smoothing support ---------------------------------------------------------------- TRUEP Task: This task will read the RL and LR data for one source from the first data set and the RL and LR data for a second source from the second data set. It is assumed that the second data set has the horn of one antenna rotated by about 90 degrees. The baselines to this antenna then allow the task to determine the full polarization D terms for all antennas. Adverbs: Data set with normal feed position INNAME.....Input UV file name (name). Standard defaults. INCLASS....Input UV file name (class). Standard defaults. INSEQ......Input UV file name (seq. #). 0 => highest. INDISK.....Disk drive # of input UV file. 0 => any. Data set with rotated feed position IN2NAME....Input UV file name (name). Standard defaults. IN2CLASS...Input UV file name (class). Standard defaults. IN2SEQ.....Input UV file name (seq. #). 0 => highest. IN2DISK....Disk drive # of input UV file. 0 => any. SOURCES....Source names to be used: SOURCE(1) for the first data set and SOURCE(2) for the second data set. SOURCE(2) = ' ' => SOURCE(2) = SOURCE(1)n QUAL.......Qualifier of source to be used. -1 => all. CALCODE....Calibrator code of sources to use. ' '=> all. TIMERANG...Time range of the data to be copied. In order: Start day, hour, min. sec, end day, hour, min. sec. Days relative to ref. date. SELBAND....Bandwidth of data to be selected. If more than one IF is present SELBAND is the width of the first IF required. Units = kHz. For data which contain multiple bandwidths/frequencies the task will insist that some form of selection be made by frequency or bandwidth. SELFREQ....Frequency of data to be selected. If more than one IF is present SELFREQ is the frequency of the first IF required. Units = MHz. FREQID.....Frequency identifier to select (you may determine which is applicable from the OPTYPE='SCAN' listing produced by LISTR). If either SELBAND or SELFREQ are set, their values override that of FREQID. However, setting SELBAND and SELFREQ may result in an ambiguity. In that case, the task will request that you use FREQID. SUBARRAY...Sub-array number to copy. 0=>all. BIF........First IF to include. 0 -> 1. EIF........Last IF to include. 0 -> BIF. Give these if you want task to loop over IF. BCHAN......First channel to copy. 0=>all. ECHAN......Highest channel to copy. 0=>all higher than BCHAN Channels are averaged unless SPECTRAL > 0 DOCALIB....If true (>0), calibrate the data using information in the specified Cal (CL) table for multi-source or SN table for single-source data. Also calibrate the weights unless DOCALIB > 99 (use this for old non-physical weights). GAINUSE....version number of the CL table to apply to multi-source files or the SN table for single source files. 0 => highest. DOPOL......If > 0 then correct data for instrumental polarization as represented in the AN or PD table. This correction is only useful if PCAL has been run or feed polarization parameters have been otherwise obtained. See HELP DOPOL for available correction modes: 1 is normal, 2 and 3 are for VLBI. 1-3 use a PD table if available; 6, 7, 8 are the same but use the AN (continuum solution) even if a PD table is present. PDVER......PD table to apply if PCAL was run with SPECTRAL true and 0 < DOPOL < 6. <= 0 => highest. BLVER......Version number of the baseline based calibration (BL) table to apply. <0 => apply no BL table, 0 => highest. FLAGVER....specifies the version of the flagging table to be applied. 0 => highest numbered table. <0 => no flagging to be applied. DOBAND.....If true (>0) then correct the data for the shape of the antenna bandpasses using the BP table specified by BPVER. The correction has five modes: (a) if DOBAND=1 all entries for an antenna in the table are averaged together before correcting the data. (b) if DOBAND=2 the entry nearest in time (including solution weights) is used to correct the data. (c) if DOBAND=3 the table entries are interpolated in time (using solution weights) and the data are then corrected. (d) if DOBAND=4 the entry nearest in time (ignoring solution weights) is used to correct the data. (e) if DOBAND=5 the table entries are interpolated in time (ignoring solution weights) and the data are then corrected. IMAGR uses DOBAND as the nearest integer; 0.1 is therefore "false". BPVER......Specifies the version of the BP table to be applied 0 => highest numbered table. <0 => no bandpass correction to be applied. SMOOTH.....Specifies the type of spectral smoothing to be applied to a uv database . The default is not to apply any smoothing. The elements of SMOOTH are as follows: SMOOTH(1) = type of smoothing to apply: 0 => no smoothing To smooth before applying bandpass calibration 1 => Hanning, 2 => Gaussian, 3 => Boxcar, 4 => Sinc To smooth after applying bandpass calibration 5 => Hanning, 6 => Gaussian, 7 => Boxcar, 8 => Sinc SMOOTH(2) = the "diameter" of the function, i.e. width between first nulls of Hanning triangle and sinc function, FWHM of Gaussian, width of Boxcar. Defaults (if < 0.1) are 4, 2, 2 and 3 channels for SMOOTH(1) = 1 - 4 and 5 - 8, resp. SMOOTH(3) = the diameter over which the convolving function has value - in channels. Defaults: 1,3,1,4 times SMOOTH(2) used when input SMOOTH(3) < net SMOOTH(2). SPECTRAL...Average spectral channels unless SPECTRAL > 0. In that case, write a new PD table. APARM......(1) Antenna having the rotated feed. (2) Estimate of rotation angle. 0 => 90 degrees. (3) = 1 => display averaged data also (ignored if SPECTRAL > 0) (4) Type of smoothing to apply after the fit 0 => no smoothing 1 => Hanning 2 => Gaussian 3 => Boxcar 4 => Sinc (i.e. sin(x)/x) (5) Diameter in channels of the smoothing function: i.e. width between first nulls of Hanning triangle and sinc function, FWHM of Gaussian, width of Boxcar. Defaults (if < 0.1) are 4, 2, 2 and 3 channels for APARM(4) = 1 - 4. (6) the diameter over which the convolving function has value - in channels. Defaults: 1, 3, 1, 4 times APARM(5) used when input APARM(6) < net APARM(5). ----------------------------------------------------------------