A Quick Test on Rotation Period Clustering for the Small Members of the Koronis Family

TL;DR

This study investigates rotation period clustering among small Koronis family asteroids to explore the presence of the Slivan state, finding no clear clustering for smaller objects possibly due to collisional effects.

Contribution

It introduces a method to separate prograde and retrograde rotators in the Koronis family based on dispersion in semimajor axis and assesses clustering in small asteroids using PTF/iPTF data.

Findings

No rotation period clustering observed for H > 12 mag asteroids.

Intermittent collisional processes may disrupt Yarkovsky-driven clustering.

Pole orientation measurements are needed to confirm results.

Abstract

Rotation period clustering in prograde/retrograde rotators might indicate the preliminary indication of the Slivan state in the Koronis family as a result of the YORP effect. We follow the general scenario of dispersion in semimajor axis of the asteroid family members to separate prograde and retrograde rotators in the Koronis family. From the available rotation periods obtained from PTF/iPTF, we can not found the rotation period clustering of objects with H grater than 12 mag in the Koronis family. This could be the result of the intermittent collisional process of small asteroids (D less than ~20 km) which leads to astray Yarkovsky drifting. Measurement of the pole orientations of our sample will verify our preliminary result and validate our method.