OSSOS. II. A Sharp Transition in the Absolute Magnitude Distribution of the Kuiper Belt’s Scattering Population
Abstract
We measure the absolute magnitude, H, distribution, dN(H) ∝ 10^{ αH }, of the scattering TransNeptunian Objects (TNOs) as a proxy for their sizefrequency distribution. We show that the Hdistribution of the scattering TNOs is not consistent with a singleslope distribution, but must transition around H _{ g } ̃ 9 to either a knee with a shallow slope or to a divot, which is a differential drop followed by second exponential distribution. Our analysis is based on a sample of 22 scattering TNOs drawn from three different TNO surveys—the CanadaFrance Ecliptic Plane Survey, Alexandersen et al., and the Outer Solar System Origins Survey, all of which provide wellcharacterized detection thresholds—combined with a cosmogonic model for the formation of the scattering TNO population. Our measured absolute magnitude distribution result is independent of the choice of cosmogonic model. Based on our analysis, we estimate that the number of scattering TNOs is (2.48.3) × 10^{5} for H _{ r } < 12. A divot Hdistribution is seen in a variety of formation scenarios and may explain several puzzles in Kuiper Belt science. We find that a divot Hdistribution simultaneously explains the observed scattering TNO, Neptune Trojan, Plutino, and Centaur Hdistributions while simultaneously predicting a large enough scattering TNO population to act as the sole supply of the JupiterFamily Comets.
 Publication:

The Astronomical Journal
 Pub Date:
 February 2016
 DOI:
 10.3847/00046256/151/2/31
 arXiv:
 arXiv:1511.02896
 Bibcode:
 2016AJ....151...31S
 Keywords:

 comets: general;
 Kuiper Belt: general;
 Astrophysics  Earth and Planetary Astrophysics
 EPrint:
 doi:10.3847/00046256/151/2/31