Asteroid taxonomic signatures from photometric phase curves
Abstract
We explore the correlation between an asteroid's taxonomy and photometric phase curve using the H, G_{12} photometric phase function, with the shape of the phase function described by the single parameter G_{12}. We explore the usability of G_{12} in taxonomic classification for individual objects, asteroid families, and dynamical groups. We conclude that the mean values of G_{12} for the considered taxonomic complexes are statistically different, and also discuss the overall shape of the G_{12} distribution for each taxonomic complex. Based on the values of G_{12} for about half a million asteroids, we compute the probabilities of C, S, and X complex membership for each asteroid. For an individual asteroid, these probabilities are rather evenly distributed over all of the complexes, thus preventing meaningful classification. We then present and discuss the G_{12} distributions for asteroid families, and predict the taxonomic complex preponderance for asteroid families given the distribution of G_{12} in each family. For certain asteroid families, the probabilistic prediction of taxonomic complex preponderance can clearly be made. In particular, the C complex preponderant families are the easiest to detect, the Dora and Themis families being prime examples of such families. We continue by presenting the G_{12}based distribution of taxonomic complexes throughout the main asteroid belt in the proper element phase space. The NysaPolana family shows two distinct regions in the proper element space with different G_{12} values dominating in each region. We conclude that the G_{12}based probabilistic distribution of taxonomic complexes through the main belt agrees with the general view of C complex asteroid proportion increasing towards the outer belt. We conclude that the G_{12} photometric parameter cannot be used in determining taxonomic complex for individual asteroids, but it can be utilized in the statistical treatment of asteroid families and different regions of the main asteroid belt.
 Publication:

Icarus
 Pub Date:
 May 2012
 DOI:
 10.1016/j.icarus.2012.02.028
 arXiv:
 arXiv:1202.2270
 Bibcode:
 2012Icar..219..283O
 Keywords:

 Astrophysics  Earth and Planetary Astrophysics
 EPrint:
 submitted to Icarus