313 New asteroid rotation periods from palomar transient factory observations

Abstract

A new asteroid rotation period survey has been carried out by using the Palomar Transient Factory (PTF). Twelve consecutive PTF fields, which covered an area of 87 deg2 in the ecliptic plane, were observed in the R band with a cadence of ∼20 minutes during 2013 February 15-18. We detected 2500 known asteroids with a diameter range of 0.5 km ≤D ≤ 200 km. Of these, 313 objects had highly reliable rotation periods and exhibited the "spin barrier" at ∼2 hr. In contrast to the flat spin-rate distribution of the asteroids with 3 km ≤D ≤ 15 km shown by Pravec et al., our results deviated somewhat from a Maxwellian distribution and showed a decrease at the spin rate greater than 5 rev day-1. One superfast rotator candidate and two possible binary asteroids were also found in this work. © 2014. The American Astronomical Society. All rights reserved..