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+ REAL FUNCTION sla_RVLSRD (R2000, D2000)
+*+
+* - - - - - - -
+* R V L S R D
+* - - - - - - -
+*
+* Velocity component in a given direction due to the Sun's motion
+* with respect to the dynamical Local Standard of Rest.
+*
+* (single precision)
+*
+* Given:
+* R2000,D2000 r J2000.0 mean RA,Dec (radians)
+*
+* Result:
+* Component of "peculiar" 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 the "dynamical" LSR,
+* 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.
+*
+* There is another type of LSR, called a "kinematical" LSR. A
+* kinematical LSR is the mean standard of rest of specified star
+* catalogues or stellar populations, and several slightly
+* different kinematical LSRs are in use. The Sun's motion with
+* respect to an agreed kinematical LSR is known as the "standard"
+* solar motion. To obtain a radial velocity correction with
+* respect to an adopted kinematical LSR use the routine sla_RVLSRK.
+*
+* Reference: Delhaye (1965), in "Stars and Stellar Systems", vol 5,
+* p73.
+*
+* Called:
+* sla_CS2C, sla_VDV
+*
+* P.T.Wallace Starlink 9 March 1994
+*
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+ IMPLICIT NONE
+
+ REAL R2000,D2000
+
+ REAL VA(3), VB(3)
+
+ REAL sla_VDV
+
+*
+* Peculiar solar motion from Delhaye 1965: in Galactic Cartesian
+* coordinates (+9,+12,+7) km/s. This corresponds to about 16.6 km/s
+* towards Galactic coordinates L2 = 53 deg, B2 = +25 deg, or RA,Dec
+* 17 49 58.7 +28 07 04 J2000.
+*
+* 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 / +0.63823, +14.58542, -7.80116 /
+
+
+
+* Convert given J2000 RA,Dec to x,y,z
+ CALL sla_CS2C(R2000,D2000,VB)
+
+* Compute dot product with solar motion vector
+ sla_RVLSRD=sla_VDV(VA,VB)
+
+ END