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+ REAL FUNCTION slRVLK (R2000, D2000)
+*+
+* - - - - - - -
+* R V L K
+* - - - - - - -
+*
+* Velocity component in a given direction due to the Sun's motion
+* with respect to an adopted kinematic Local Standard of Rest.
+*
+* (single precision)
+*
+* Given:
+* R2000,D2000 r J2000.0 mean RA,Dec (radians)
+*
+* Result:
+* Component of "standard" solar motion in direction R2000,D2000 (km/s)
+*
+* Sign convention:
+* The result is +ve when the Sun is receding from the given point on
+* the sky.
+*
+* Note: The Local Standard of Rest used here is one of several
+* "kinematical" LSRs in common use. A kinematical LSR is the
+* mean standard of rest of specified star catalogues or stellar
+* populations. The Sun's motion with respect to a kinematical
+* LSR is known as the "standard" solar motion.
+*
+* There is another sort of LSR, the "dynamical" LSR, which is a
+* point in the vicinity of the Sun which is in a circular orbit
+* around the Galactic centre. The Sun's motion with respect to
+* the dynamical LSR is called the "peculiar" solar motion. To
+* obtain a radial velocity correction with respect to the
+* dynamical LSR use the routine slRVLD.
+*
+* Reference: Delhaye (1965), in "Stars and Stellar Systems", vol 5,
+* p73.
+*
+* Called:
+* slCS2C, slVDV
+*
+* P.T.Wallace Starlink 11 March 1994
+*
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+*
+* License:
+* 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 (see SLA_CONDITIONS); if not, write to the
+* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+* Boston, MA 02110-1301 USA
+*
+* Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+*-
+
+ IMPLICIT NONE
+
+ REAL R2000,D2000
+
+ REAL VA(3), VB(3)
+
+ REAL slVDV
+
+*
+* Standard solar motion (from Methods of Experimental Physics, ed Meeks,
+* vol 12, part C, sec 6.1.5.2, p281):
+*
+* 20 km/s towards RA 18h Dec +30d (1900).
+*
+* The solar motion is expressed here in the form of a J2000.0
+* equatorial Cartesian vector:
+*
+* VA(1) = X = -SPEED*COS(RA)*COS(DEC)
+* VA(2) = Y = -SPEED*SIN(RA)*COS(DEC)
+* VA(3) = Z = -SPEED*SIN(DEC)
+
+ DATA VA / -0.29000, +17.31726, -10.00141 /
+
+
+
+* Convert given J2000 RA,Dec to x,y,z
+ CALL slCS2C(R2000,D2000,VB)
+
+* Compute dot product with solar motion vector
+ slRVLK=slVDV(VA,VB)
+
+ END