; UVFIXPRM ;--------------------------------------------------------------- ;! Parameter adverb array for task UVFIX ;# ADVERB UV ;----------------------------------------------------------------------- ;; Copyright (C) 1995, 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 ;----------------------------------------------------------------------- UVFIXPRM LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC ---------------------------------------------------------------- UVFIXPRM Type: Adverb (Real(20)) Use: The task specific parameters for UVFIX. Specifies geometry and time information. Null value: Usually 0. Tasks: HAFIX....Recomputes u,v,w when time is hour angle (UVdata is output of TI2HA) UVFIX....Recomputes u, v, and w with optional tangent point shift. Details: 1 => array type, 0=VLA, 1=VLBI, 2=other. 2 => array number, 0 => loop over all. 3+4 => array BX, meters. (proper defaults for UVFIXPRM(1)= 5+6 => array BY, meters. 0 or 1) 7+8 => array BZ, meters. Here X is in the direction of the intersection of the meridian of the reference location (long=0 for earth centered) and the equator; Y is 90 deg. EAST along the equator from X; Z is in the direction of the N. pole. Note that: BX = UVFIXPRM(3) + UVFIXPRM(4), BY = UVFIXPRM(5) + UVFIXPRM(6), BZ = UVFIXPRM(7) + UVFIXPRM(8). The addition of two parameters allows the coordinates to be specified with more precision than a single adverb allows; on a 32-bit machines adverb values are only accurate to 7 significant digits. The array center is changed only if the two values are not zero - set set 10**-20 if 0 is desired. NOTE: EVLA uses the earth center (0,0,0). 11 => UT1-UTC in seconds. Default = value in AN file. (Use the default!) 12 => (uv data time)-UTC in seconds. Default = value in AN file under keyword DATUTC or, for the VLA (not EVLA), use the accumulated leap seconds.. (Use the default!) Accurate values for both UT1-UTC and IAT-UTC can be obtained from USNO Bulletin no. 7. A table of leap seconds is maintained in AIPS. 13 => Clock error. **** N.B. FILLM was corrected on 6 July 2007 in version 31DEC07 to write data times centered within the integration. Do not use this option for data loaded with that or later versions. **** For data loaded with earlier versions of FILLM, the time labels are in error by half of the MODCOMP online averaging time. Usually 5 seconds. (no default). The clock error is subtracted from times in the file. EVLA times are not in error. 14 => Frequency in Hz. If <= 0, the value in the AN, FQ, and SU files will be used. 15 OB table number; 0 => 1 16 The antenna number of the orbiting antenna; 0=>there is no an orbiting antenna; It is assumed that there is at most one orbiting antenna. Parameters #15 and #16 are not used for conventional (ground based) interferometry. Thus zeros are normally desirable. 17 Besselian epoch of data. When converting B1950 to J2000, the coordinates must first be converted to the observation date and then converted to J2000. 0 => 1979.3 which is okay for most VLA data. 18 0 => include differential aberration(Lorentz factor) 1 => not includes differential aberration(Lorentz factor) 20 > 0 => Do not recompute U, V, W. Users of the ATCA may want this option since the recomputation changes -NCP to -SIN projection for the U,V,W coordinates. Under all other circumstances, this option is not desirable. ----------------------------------------------------------------