Abstract
Context. Information about shapes and spin states of individual asteroids is important for the study of the whole asteroid population.
For asteroids from the main belt, most of the shape models available now have been reconstructed from disk-integrated photometry by the lightcurve inversion method. Aims.
We want to significantly enlarge the current sample (similar to 350) of available asteroid models. Methods.
We use the lightcurve inversion method to derive new shape models and spin states of asteroids from the sparse-in-time photometry compiled in the Lowell Photometric Database. To speed up the time-consuming process of scanning the period parameter space through the use of convex shape models, we use the distributed computing project Asteroids@home, running on the Berkeley Open Infrastructure for Network Computing (BOINC) platform.
This way, the period-search interval is divided into hundreds of smaller intervals. These intervals are scanned separately by different volunteers and then joined together.
We also use an alternative, faster, approach when searching the best-lit period by using a model of triaxial ellipsoid. By this, we can independently confirm periods found with convex models and also find rotation periods for some of those asteroids for which the convex-model approach gives too many solutions.
Results. From the analysis of Lowell photometric data of the first 100 000 numbered asteroids, we derived 328 new models.