; HORUS ;--------------------------------------------------------------- ;! makes images from unsorted UV data, applying any calibration ;# Task Imaging AP ;----------------------------------------------------------------------- ;; Copyright (C) 1995-1997, 1999-2000, 2004, 2006, 2008 ;; 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 ;----------------------------------------------------------------------- HORUS LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC HORUS Task to calibrate and image data INNAME Input UV file name (name) INCLASS Input UV file name (class) INSEQ 0.0 9999.0 Input UV file name (seq. #) INDISK 0.0 9.0 Input UV file disk unit # SOURCES Source list QUAL -10.0 Calibrator qualifier -1=>all TIMERANG Time range to use UVRANGE 0. Min & max baseline (klambda) STOKES Stokes type to image OPTYPE 'SUM ' or 'LINE' SELBAND Bandwidth to select (kHz) SELFREQ Frequency to select (MHz) FREQID Freq. ID to select. BIF 0.0 100.0 Lowest IF number 0=>all EIF 0.0 100.0 Highest IF number 0=>all BCHAN 0.0 2048.0 Lowest channel number 0=>all ECHAN 0.0 2048.0 Highest channel number CHINC Channel incr. between maps. SUBARRAY 0.0 1000.0 Subarray, 0=>all 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 correct polarization. BLVER BL table to apply. FLAGVER Flag table version DOBAND -1.0 10.0 If >0 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. OUTNAME Output image name 1st 4 char. used. OUTSEQ -1.0 9999.0 Output image seq. # OUTDISK 0.0 9.0 Output image disk unit #. IMSIZE 32. 4096. Image size (X,Y) is pixels CELLSIZE 1.E-12 (X,Y) size of grid in asec SHIFT (X,Y) image shift in asec UVTAPER 0. (U,V) gaussian taper units are kilolambda UVWTFN UV dist. weight function blank => uniform UVBOX 0. 128. Additional rows and columns used in weighting. Use 0. ZEROSP 0-spacing fluxes and weights XTYPE 0. 10. Conv. function type in x default spheroidal YTYPE 0. 10. Conv. function type in y default spheroidal XPARM Conv. function parms for x YPARM Conv. function parms for y GUARD -1.0 0.9 x,y guard band fractional radius BADDISK 0.0 9999.0 Disks to avoid for scratch ---------------------------------------------------------------- HORUS Task: Image a data set with optional application of calibration and editing. Multiple sources may be processed in a single run. HORUS will process either "XY" or "TB" sorted data but the maximum size of the image which can be produced from TB ordered data is limited by the size of the "AP". A 64kword AP can make a 128x128 image. Adverbs: 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. SOURCES....Source list. One output file will be made per source. '*' = all; a "-" before a source name means all except ANY source named. QUAL.......Only sources with a source qualifier number in the SU table matching QUAL will be used if QUAL is not -1. TIMERANG...Time range of the data to be imaged. In order: Start day, hour, min. sec, end day, hour, min. sec. Days relative to ref. date. UVRANGE....(Minimum,Maximum) baseline (kilolambda) in map. STOKES.....The desired Stokes type of the output data: 'I','V','Q','U','R', or 'L'. Anything else => 'I' OPTYPE.....The type of image, 'SUM' = all channels in the same image, 'LINE' = each channel in a separate plane. For 'LINE' only IF=BIF is processed. All others are set to 'LINE' if there is more than one frequency channel or 'SUM ' if not. 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 overide that of FREQID. However, setting SELBAND and SELFREQ may result in an ambiguity. In that case, the task will request that you use FREQID. BIF........First IF to image. 0 => 1. EIF........Highest IF to image. 0=>all higher than BIF in SUM mode. EIF is forced to BIF in LINE mode (with a warning if EIF was changed). BCHAN......First channel to image. 0 => 1. ECHAN......Highest channel to image. 0 => all higher than BCHAN. CHINC......Number of input planes to skip between maps. (0=>1) SUBARRAY...Subarray number to image. 0=>all. 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 multisource 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 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. BLVER......Version number of the baseline based calibration (BL) table to appply. <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. BPVER......Specifies the version of the BP table to be applied plotted (if APARM(8)=2) or applied (if DOBAND > 0 and APARM(8) .NE. 2). 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). OUTNAME....1st 4 characters of the output image name. The following 8 are the 1st 8 of the source name. OUTSEQ.....Output image name (seq. #). 0 => highest unique OUTDISK....Disk drive # of output image. 0 => highest with space for the file. IMSIZE.....(X,Y) image size in pixels. Must be a power of 2 on each side from 32X32 to 4096X4096. For TB ordered data the actual limit depends on the amount of "AP" memory available. CELLSIZE...(X,Y) pixel separation in asec. SHIFT......(X,Y) shift of map center from phase center in asec. Map center = Phase center + shift. If X>0 & Y>0, source shifts to south-west (down & right). See HELP SHIFT. Shifts are in arc seconds at the initial reference position making RA = RA0 + SHIFT(1)/cos(DEC) and DEC = DEC0 + SHIFT(2). UVTAPER....(U,V) gaussian taper (kilolambda) at 30% level UVWTFN.....Weighting function of (u-v) place. blank=>Uniform; 'NA'=>Natural UVBOX......(U,V) box size for smoothing. Only used if data XY sorted. ZEROSP.....Zero-spacing value of I,Q,U,V, Weight XTYPE......Convolution function type in X-direction 1=Pillbox, 2=exponential, 3=Sinc, 4=Exp*Sinc, 5=Spheroidal, 6=exp*BESSJ1(x)/x. <= 0 or > 5 -> 5. YTYPE.....Convolution function type in Y-direction XPARM.....Array containing parameters for XTYPE. See HELP UVnTYPE when n=convolution type. YPARM.....Array containing parameters for YTYPE. GUARD.....Fraction of the x and y radius for which uv samples are not allowed. < 0 => just enough to avoid mathematical errors in the convolution. 0 => 0.3 * SQRT(taper weight at 0.3 from edge). BADDISK....A list of disks on which scratch files are not to be placed. This will not affect the output file. ---------------------------------------------------------------- HORUS: Task to make images from uv data with optional calibration and editing. Documentor: W. D. Cotton Related Programs: All calibration routines Horus was the son of the Eqyptian god and goddess Osirus and Isis. Osirus was the first Egyptian king, a just and wise ruler who invented civilization and agriculture. His evil brother Set was jealous of Osirus and wanted his throne and his wife/sister. Set killed Osirus and chopped his body into 17 pieces and threw them into the Nile. Isis collected all of his parts except his penis which had been eaten by crabs. She made a copy of his missing member and reassembled and embalmed his body. With the help of the mummy, she conceived Horus to avenge his father's death and to assume his throne. She then raised him in a marsh to protect his from his uncle. After a long and undecisive war, Set took the matter to court - a tribunal of the gods. The gods were unable to decide if the issue should be settled on the basis of might or right. After the trial had lasted for 80 years, the gods started bickering. The minor god Baba taunted presiding god Ra-Harakhte (who was becoming senile) that "Your shrine is empty!" and he went into a snit and wouldn't come back until his daughter Hathor exposed herself to him. Isis then tricked Set into making statments which were damaging to his case and a decision was reached in Horus' favor. Horus then married Hathor and assumed the throne of Osirus. After his death was thus avenged, Osirus was resurrected and became the king of the underworld (near present day Libya) and the judge of the dead. The pharoahs of Egypt thereafter claimed to be the living incarnation of Horus. (ref. V. Ions, 1982, "Egyptian Mythology", Peter Bedrick Books, New York)