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SUBROUTINE sla_ADDET (RM, DM, EQ, RC, DC)
*+
* - - - - - -
* A D D E T
* - - - - - -
*
* Add the E-terms (elliptic component of annual aberration)
* to a pre IAU 1976 mean place to conform to the old
* catalogue convention (double precision)
*
* Given:
* RM,DM dp RA,Dec (radians) without E-terms
* EQ dp Besselian epoch of mean equator and equinox
*
* Returned:
* RC,DC dp RA,Dec (radians) with E-terms included
*
* Note:
*
* Most star positions from pre-1984 optical catalogues (or
* derived from astrometry using such stars) embody the
* E-terms. If it is necessary to convert a formal mean
* place (for example a pulsar timing position) to one
* consistent with such a star catalogue, then the RA,Dec
* should be adjusted using this routine.
*
* Reference:
* Explanatory Supplement to the Astronomical Ephemeris,
* section 2D, page 48.
*
* Called: sla_ETRMS, sla_DCS2C, sla_DCC2S, sla_DRANRM, sla_DRANGE
*
* P.T.Wallace Starlink 18 March 1999
*
* Copyright (C) 1999 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION RM,DM,EQ,RC,DC
DOUBLE PRECISION sla_DRANRM
DOUBLE PRECISION A(3),V(3)
INTEGER I
* E-terms vector
CALL sla_ETRMS(EQ,A)
* Spherical to Cartesian
CALL sla_DCS2C(RM,DM,V)
* Include the E-terms
DO I=1,3
V(I)=V(I)+A(I)
END DO
* Cartesian to spherical
CALL sla_DCC2S(V,RC,DC)
* Bring RA into conventional range
RC=sla_DRANRM(RC)
END
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