THE CANADA-FRANCE ECLIPTIC PLANE SURVEY—FULL DATA RELEASE: THE ORBITAL STRUCTURE OF THE KUIPER BELT

Abstract

We report the orbital distribution of the trans-neptunian objects (TNOs)\ndiscovered during the Canada-France Ecliptic Plane Survey, whose discovery\nphase ran from early 2003 until early 2007. The follow-up observations started\njust after the first discoveries and extended until late 2009. We obtained\ncharacterized observations of 321 sq.deg. of sky to depths in the range g ~\n23.5--24.4 AB mag. We provide a database of 169 TNOs with high-precision\ndynamical classification and known discovery efficiency. Using this database,\nwe find that the classical belt is a complex region with sub-structures that go\nbeyond the usual splitting of inner (interior to 3:2 mean-motion resonance\n[MMR]), outer (exterior to 2:1 MMR), and main (in between). The main classical\nbelt (a=40--47 AU) needs to be modeled with at least three components: the\n`hot' component with a wide inclination distribution and two `cold' components\n(stirred and kernel) with much narrower inclination distributions. The hot\ncomponent must have a significantly shallower absolute magnitude (Hg)\ndistribution than the other two components. With 95% confidence, there are\n8000+1800-1600 objects in the main belt with Hg <= 8.0, of which 50% are from\nthe hot component, 40% from the stirred component and 10% from the kernel; the\nhot component's fraction drops rapidly with increasing Hg. Because of this, the\napparent population fractions depend on the depth and ecliptic latitude of a\ntrans-neptunian survey. The stirred and kernel components are limited to only a\nportion of the main belt, while we find that the hot component is consistent\nwith a smooth extension throughout the inner, main and outer regions of the\nclassical belt; the inner and outer belts are consistent with containing only\nhot-component objects. The Hg <= 8.0 TNO population estimates are 400 for the\ninner belt and 10,000 for the outer belt within a factor of two.\n