Analysis for Cellinoid shape model in inverse process from lightcurves

摘要

Based on the special shape first introduced by Alberto Cellino, which consists of eight ellipsoidal octants with the constraint that adjacent octants must have two identical semi-axes, an efficient algorithm to derive the physical parameters, such as the rotational period, pole orientation, and overall shape from either lightcurves or sparse photometric data of asteroids, is developed by Lu et al. and named as 'Cellinoid' shape model. For thoroughly investigating the relationship between the morphology of the synthetic lightcurves generated by the Cellinoid shape and its six semi-axes as well as rotational period and pole, the numerical tests are implemented to compare the synthetic lightcurves generated by three Cellinoid models with different parameters in this article. Furthermore, from the synthetic lightcurves generated by two convex shape models of (6) Hebe and (4179) Toutatis, the inverse process based on Cellinoid shape model is applied to search the best-fit parameters. Especially, for better simulating the real observations, the synthetic lightcurves are generated under the orbit limit of the two asteroids. By comparing the results derived from synthetic lightcurves observed in one apparition and multiple apparitions, the performance of Cellinoid shape model is confirmed and the suggestions for observations are presented. Finally, the whole process is also applied to real observed lightcurves of (433) Eros and the derived results are consistent with the known results.