313 new asteroid rotation periods from Palomar Transient Factory observations

TL;DR

This study used Palomar Transient Factory observations to determine rotation periods for 313 asteroids, revealing a spin barrier at 2 hours, deviations from Maxwellian distribution, and identifying potential super-fast rotators and binaries.

Contribution

First large-scale asteroid rotation survey using PTF data, providing new rotation periods and insights into asteroid spin rate distributions and binary candidates.

Findings

313 asteroids with reliable rotation periods identified

Detected the spin barrier at approximately 2 hours

Observed deviations from Maxwellian spin rate distribution

Abstract

A new asteroid rotation period survey have been carried out by using the Palomar Transient Factory (PTF). Twelve consecutive PTF fields, which covered an area of 87 deg$^2$ in the ecliptic plane, were observed in $R$ band with a cadence of $\sim$20 min during February 15--18, 2013. We detected 2500 known asteroids with a diameter range of 0.5 km $\leq D \leq$ 200 km. Of these, 313 objects had highly reliable rotation periods and exhibited the "spin barrier" at $\sim2$ hours. In contrast to the flat spin rate distribution of the asteroids with 3 km $\leq D \leq$ 15 km shown by Pravec et al. (2008), our results deviated somewhat from a Maxwellian distribution and showed a decrease at the spin rate greater than 5 rev/day. One super-fast-rotator candidate and two possible binary asteroids were also found in this work.