SLA_PREBN - Precession Matrix (FK4)   

ACTION:

Generate the matrix of precession between two epochs, using the old, pre IAU 1976, Bessel-Newcomb model, in Andoyer's formulation.

CALL:

CALL sla_PREBN (BEP0, BEP1, RMATP)

GIVEN:

BEP0 beginning Besselian epoch

BEP1 D ending Besselian epoch

RETURNED:

RMATP precession matrix

NOTE:

The matrix is in the sense:

v₁ = M$\cdot$v₀

where v₁ is the star vector relative to the mean equator and equinox of epoch BEP1, M is the $3\times3$ matrix RMATP and v₀ is the star vector relative to the mean equator and equinox of epoch BEP0.

REFERENCE:

Smith et al., 1989. Astr.J. 97, 269.