The Pan-Starrs 1 Discoveries of Five New Neptune Trojans

Abstract

In this work, we report the detection of seven Neptune Trojans (NTs) in the Pan-STARRS 1 (PS1) survey. Five of these are new discoveries, consisting of four L4 Trojans and one L5 Trojan. Our orbital simulations show that the L5 Trojan stably librates for only several million years. This suggests that the L5 Trojan must be of recent capture origin. On the other hand, all four new L4 Trojans stably occupy the 1:1 resonance with Neptune for more than 1 Gyr. They can, therefore, be of primordial origin. Our survey simulation results show that the inclination width of the NT population should be between 7°and 27°at >95% confidence, and most likely ∼11°. In this paper, we describe the PS1 survey, the Outer Solar System pipeline, the confirming observations, and the orbital/physical properties of the new NTs.

A dearth of small members in the Haumea family revealed by OSSOS

“…These objects are: 2014 LO 28 , 2014YB 50 , 2015FN 345 , 2013RM 98 , 2014 , and 2014 QW 441 , see Table 1. All are within the brightness limit to which Pan-STARRS is reported to be complete (m w =22.5) (Lin et al 2016), or m r ∼ 22.0. We exclude 2010 OO 127 , because of its possible resonance modification and lack of observations in w band.…”

“…To quantify the effect of the completeness limit, we used the OSSOS Survey Simulator to test a very simple model of the Pan-STARRS1 'The Solar System Survey'. No pointing and depth per observing region is provided by the Pan-STARRS1 survey at this time, however the Solar System Survey covers the majority of the ecliptic plane to ±30 • to a limiting magnitude of m w =22.5 (Lin et al 2016). Based on reported Pan-STARRS1 survey limiting magnitude in w, we use a limiting magnitude of m r ∼ 22.05 for Haumea family members for all survey regions.…”