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.help fk5hz Jun99 "Slalib Package"
.nf

      SUBROUTINE slF5HZ (R5,D5,EPOCH,RH,DH)

     - - - - - -
      F 5 H Z
     - - - - - -

  Transform an FK5 (J2000) star position into the frame of the
  Hipparcos catalogue, assuming zero Hipparcos proper motion.

  (double precision)

  This routine converts a star position from the FK5 system to
  the Hipparcos system, in such a way that the Hipparcos proper
  motion is zero.  Because such a star has, in general, a non-zero
  proper motion in the FK5 system, the routine requires the epoch
  at which the position in the FK5 system was determined.

  Given:
     R5        d      FK5 RA (radians), equinox J2000, epoch EPOCH
     D5        d      FK5 Dec (radians), equinox J2000, epoch EPOCH
     EPOCH     d      Julian epoch (TDB)

  Returned (all Hipparcos):
     RH        d      RA (radians)
     DH        d      Dec (radians)

  Called:  slDS2C, slDAVM, slDIMV, slDMXV, slDC2S

  Notes:

  1)  The FK5 to Hipparcos transformation consists of a pure
      rotation and spin;  zonal errors in the FK5 catalogue are
      not taken into account.

  2)  The published orientation and spin components are interpreted
      as "axial vectors".  An axial vector points at the pole of the
      rotation and its length is the amount of rotation in radians.

  3)  See also slFK5H, slHFK5, slHF5Z.

  Reference:

     M.Feissel & F.Mignard, Astron. Astrophys. 331, L33-L36 (1998).

  P.T.Wallace   Starlink   7 October 1998

  Copyright (C) 1998 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

.fi
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