Follow-up observations for the Asteroid Catalog using AKARI Spectroscopic Observations

Abstract

Abstract In the 1–2.5 μm range, spectroscopic observations are made on the AcuA-spec asteroids, the spectra of which were obtained in a continuous covered mode between 2.5–5.0 μm by AKARI. Based on the Bus–DeMeo taxonomy (DeMeo et al. 2009, Icarus, 202, 160), all the AcuA-spec asteroids are classified, using both published and our observational data. Additionally, taking advantage of the Bus–DeMeo taxonomy characteristics, we constrain the characteristic of each spectral type by combining the taxonomy results with the other physical observational data from colorimetry, polarimetry, radar, and radiometry. As a result, it is suggested that certain C-, Cb-, B-type, dark X-, and D-complex asteroids have spectral properties compatible with those of anhydrous interplanetary dust particles with tiny bright material, such as water ice. This supports the proposal regarding the C-complex asteroids (Vernazza et al. 2015, ApJ, 806, 204; 2017, AJ, 153, 72). A combination of the Bus–DeMeo taxonomy for AcuA-spec asteroids with other physical clues, such as the polarimetric inversion angle, radar albedo, and mid-infrared spectroscopic spectra, will be beneficial for surface material constraints from the AcuA-spec asteroid observations.