PRIMASS visits Hilda and Cybele groups

Abstract

The Cybele and Hilda dynamical groups delimit the outer edge of the asteroid belt. Their compositional distribution is a key element to constrain evolutionary models of the Solar System. In this paper, we present a compositional analysis of these populations using spectroscopic observations, SDSS and NEOWISE data. As part of the PRIMASS (Primitive Asteroids Spectroscopic Survey), we acquired visible spectra of 18 objects in Hilda or Cybele groups with the Goodman High Throughput Spectrometer at the 4.1m SOAR telescope and 20 near-IR spectra of Hilda objects with Near Infrared Camera Spectrograph at the 3.56m TNG. The sample is enlarged with spectra taken from the literature in order to increase our statistical analysis. The spectra were inspected for aqueous alteration bands and other spectral features that can be linked to compositional constraints. The analysis shows a continuous distribution of compositions from the main-belt to the Cybele, Hilda and Trojan regions. We also identify a population in the Trojans group not present in Hilda or Cybele objects.

26 pages, 10 figures

References in corpus (6)

• Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - preliminary results
• Asteroid families in the first order resonances with Jupiter
• The evolution of asteroids in the jumping-Jupiter migration model
• Compositional study of asteroids in the Erigone collisional family using visible spectroscopy at the 10.4 m GTC
• Astronomical Observations of Volatiles on Asteroids
• The color-magnitude distribution of Hilda asteroids: Comparison with Jupiter Trojans

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