SLA_ADDET - Add E-terms of Aberration   

ACTION:

Add the E-terms (elliptic component of annual aberration) to a pre IAU 1976 mean place to conform to the old catalogue convention.

CALL:

CALL sla_ADDET (RM, DM, EQ, RC, DC)

GIVEN:

$$[\,\alpha,\delta\,]$$ RM,DM

EQ D Besselian epoch of mean equator and equinox

RETURNED:

$$[\,\alpha,\delta\,]$$ RC,DC

NOTE:

Most star positions from pre-1984 optical catalogues (or obtained by astrometry with respect to such stars) have the E-terms built-in. 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 $[\,\alpha,\delta\,]$ should be adjusted using this routine.

REFERENCE:

Explanatory Supplement to the Astronomical Ephemeris, section 2D, page 48.