; CXIMAGR ;--------------------------------------------------------------- ;! Grid UV data into a complex image, Fourier transform, Clean ;# PROCEDURE UV IMAGING ;----------------------------------------------------------------------- ;; Copyright (C) 2020 ;; 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 ;----------------------------------------------------------------------- CXIMAGR LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC CXIMAGR: Task to make and Clean complex images INNAME UV data (name). INCLASS UV data (class). INSEQ 0.0 9999.0 UV data (seq. #). 0 => high INDISK Disk unit #. 0 => any OUTNAME Image data (name). OUTSEQ 0.0 9999.0 Image data (seq. #). 0=>high OUTDISK Disk unit #. 0 => any BIF 0.0 100.0 Lowest IF number 0=1 EIF 0.0 100.0 Highest IF number BCHAN 0.0 2048.0 Low channel number 0=>1 ECHAN 0.0 2048.0 High channel number DPARM Control info: (7) > 0 => do NOT divide by the summed weights (8) > 0 -> use XTYPE, YTYPE and interpolate to grid (10) Use data weight to the power 1/DPARM(10) SCALR3 -1. 1. > 0 => do not grid Hermitian IMSIZE 1.0 16384.0 Output image size in x,y CELLSIZE 0.000001 Cell size (arc sec) DOROBUST -1.0 1.0 > 0 use ROBUST weighting ROBUST -5.0 5.0 Brigg's robustness parameter NITER Maximum # of CLEAN components <= 0 -> no CXCLN GAIN 0.0 2.0 CLEAN loop gain FLUX 0.0 Min. residual in window (Jy) BMAJ FWHM(asec) maj. axis CLEAN restoring beam. 0 -> proc will fit QBM001 BMIN FWHM(asec) min. axis CLEAN restoring beam. BPA -360.0 360.0 CLEAN beam position angle NBOXES 0.0 50.0 Number of boxes for CLEAN CLBOX 0.0 4096.0 Four coordinates for each box BADDISK Disk to avoid for scratch. ---------------------------------------------------------------- CXIMAG Type: Procedure Use: Grids UV data to make images in U and V of the real and imaginary parts of the data and of the sampling function using UVIMG. Then it runs FFT on these "images" to make complex map-plane images. Finally, and optonally, it runs CXCLN. The u-v plane images are assigned classes CXreal, CXimag, and CXbeam. The mape plane images are given classes QIM001, UIM001, QBM001, UBM001, QCL001, and UCL001. (These classes are to satisfy the requirements of CXCLN.) The input data should be a single-source, fully calibrated data set. All included spectral channels will be "averaged". DPARM(8) was added to signal your intention to use convolving functions when interpolating to the grid. This may be desirable for this operation. The spheroidal convolving function is used. DOROBUST was added to allow for ROBUST-tempered uniform weighting. Adverbs: INNAME.....UV file name (name). Standard defaults. INCLASS....UV file name (class). Standard defaults. INSEQ......UV file name (seq. #). 0 => highest. INDISK.....Disk unit #. 0 => any. OUTNAME....Image file name (name). Standard defaults. OUTSEQ.....Image file name (seq. #). 0 => highest. OUTDISK....Output disk unit #. Standard defaults. BIF........Lowest IF to grid. IF will be axis 4. EIF........Highest IF to grid. 0 => highest. BCHAN......First channel to grid. 0 => 1. ECHAN......Last channel to grid. 0 => highest. DPARM......Control info: (1-6, 9 set by proc) (7) > 0 => do NOT divide by the count (or sum of convolution weights). Makes image a convolution such as done by IMAGR, UVMAP, et al. <= 0 => do divide by the sum of counts or convolution function weights in each cell. Makes image an interpolation of the data. (8) > 0 => use spheroidal convolution function rather than a 1-cell pillbox. <= 0 => put each sample at the nearest grid cell. (10) > 0 => use data weight when gridding to the power 1/DPARM(10) NOTE WELL: data weights are ignored if DPARM(10) is not set! SCALR3.....> 0 -> do NOT grid the Hermitian point of the visibility IMSIZE.....X,Y output image size, NO DEFAULT, power of 2 strongly recommended CELLSIZE...The "Q" and "U" image cell sizes in seconds of arc. NO DEFAULT. DOROBUST...> 0 => Do uniform -> natural weighting If > 0, then DPARM(7) is set to 1 so that weighting is done by this process rather than normalizing by counts or sum of weights. ROBUST.....Brigg's robustmess parameter. -4 uniform, 4 natural See help file for details. GAIN........The CLEAN loop gain. 0 => 0.10 NITER.......CLEAN iteration limit. <= 0 -> no CXCLN FLUX........Stop CLEAN when abs(resid. image max in CLEAN window) < FLUX (Jy). BMAJ........The FWHM (asec) major axis of the restoring beam. The parameters of the restoring beam should be provided. If <= 0, the procedure will try JMFIT on the QBM001 image. BMIN........The FWHM (asec) minor axis of the restoring beam. BPA.........The position angle in the unrotated image of BMAJ. NBOXES......Number (<=50) of rectangular search boxes. 0 => 1 CLBOX.......A 4x50 array with the BLC and TRC of each box. 0 => use inner quarter of input map (first box) 0 => ignore box (boxes 2 - 50) BADDISK....Disk numbers to avoid for scratch files. Scratch files may be created by the sorting routines if calibration or flagging is applied. ----------------------------------------------------------------