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      REAL FUNCTION slRVLD (R2000, D2000)

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      R V L D
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  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 slRVLK.

  Reference:  Delhaye (1965), in "Stars and Stellar Systems", vol 5,
              p73.

  Called:
     slCS2C, slVDV

  P.T.Wallace   Starlink   9 March 1994

  Copyright (C) 1995 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

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