Trans-Neptunian Objects with Hubble Space Telescope ACS/WFC

TL;DR

This paper presents a new Hubble Space Telescope method for quickly discovering trans-neptunian objects, reports 14 new objects, and analyzes their size distribution and formation history.

Contribution

The paper introduces a rapid search technique for trans-neptunian objects using HST ACS/WFC and reports new discoveries and insights into their size distribution and origins.

Findings

Discovered 14 new trans-neptunian objects in archival HST data.

Size distribution of small objects is similar across populations, supporting collisional evolution.

Identified an equal-mass binary among the discovered objects.

Abstract

We introduce a novel search technique that can identify trans-neptunian objects in three to five exposures of a pointing within a single Hubble Space Telescope orbit. The process is fast enough to allow the discovery of candidates soon after the data are available. This allows sufficient time to schedule follow up observations with HST within a month. We report the discovery of 14 slow-moving objects found within 5\circ of the ecliptic in archival data taken with the Wide Field Channel of the Advanced Camera for Surveys. The luminosity function of these objects is consistent with previous ground-based and space-based results. We show evidence that the size distribution of both high and low inclination populations is similar for objects smaller than 100 km, as expected from collisional evolution models, while their size distribution differ for brighter objects. We suggest the two populations formed in different parts of the protoplanetary disk and after being dynamically mixed have collisionally evolved together. Among the objects discovered there is an equal mass binary with an angular separation ~ 0."53.