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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:

RM,DM D $[\,\alpha,\delta\,]$ without E-terms (radians)
EQ D Besselian epoch of mean equator and equinox

RETURNED:

RC,DC D $[\,\alpha,\delta\,]$ with E-terms included (radians)

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.


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SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
12 October 1999
E-mail:ptw@star.rl.ac.uk