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.help rvlsrk Jun99 "Slalib Package"
.nf

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

.fi
.endhelp