Various aspects of numerical determination of nutation constants. II - an improved nutation series for the deformable earth

The errors in the IAU nutation series detected by VLBI are examined. A new, consistent nutation series is derived for application in real data analysis. A model is proposed in which Wahr's (1981) normal mode expansion is retained and Wahr's numerical coefficients are revised, based on various geophysical mechanisms and in accordance with VLBI observations. This revised model is used to derive the whole new nutation series for the deformable earth from the nutation series for the rigid earth derived by Zhu et al. (1989). Tables of the final series are presented, including 130 terms when amplitudes less than 0.05 marcsec are neglected.