6 Conclusions

 The aim of this paper was to present a new and complete series for the nutation of a rigid Earth model using the geophysical approach. The originality of this work is that a completely independent analytical computation method has been established. Using the most precise tidal potential model HW95 (Hartmann & Wenzel 1995a,b) and a single computation method for all nutation terms results in a precise nutation series H96NUT. All contributions up to 0.45 $\mathrm \mu$as were taken into account leading to 699 nutation terms. This is an improvement by one order of magnitude in the truncation threshold comparing with the series of KS90. The underlying theory, the main results, some error estimations and a comparison with other recent nutation series were presented. It has been shown that except for the long-periodic and largest nutation terms this computation method can compete with the traditional method and is a useful validation of the existing nutation series. The nutation series H96NUT for the figure axis, the angular momentum axis and the rotation axis together with a standard Fortran-77 or an ANSI-C program to evaluate these series are available at the URL:
ftp://astro.geo.tu-dresden.de/pub/h96nut.

Acknowledgements

We deeply thank Dr. J.G. Williams (Pasadena), Dr. J. Souchay (Paris), F. Roosbeek and Dr. V. Dehant (Bruxelles) for their various comments and advices to this paper. T.H. and C.R. were supported by the Sonderforschungsbereich 228 (Special Collaborative Programme) of the DFG. The fruitful cooperation with Prof. Wenzel (Karlsruhe) on the tidal potential HW95, without this work could not have been done, is gratefully acknowledged. The comments and corrections of the referee (J. Souchay) improved the paper substantially.