English

OSSOS II: A Sharp Transition in the Absolute Magnitude Distribution of the Kuiper Belt's Scattering Population

Earth and Planetary Astrophysics 2016-02-03 v2

Abstract

We measure the absolute magnitude, HH, distribution, dN(H)10αHdN(H) \propto 10^{\alpha H} of the scattering Trans-Neptunian Objects (TNOs) as a proxy for their size-frequency distribution. We show that the H-distribution of the scattering TNOs is not consistent with a single-slope distribution, but must transition around Hg9H_g \sim 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 Canada-France Ecliptic Plane Survey (CFEPS, Petit et al. 2011), Alexandersen et al. (2014), and the Outer Solar System Origins Survey (OSSOS, Bannister et al. 2016), all of which provide well characterized 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 number of scattering TNOs is (2.4-8.3)×105\times 10^5 for Hr<12H_r < 12. A divot HH-distribution is seen in a variety of formation scenarios and may explain several puzzles in Kuiper Belt science. We find that a divot HH-distribution simultaneously explains the observed scattering TNO, Neptune Trojan, Plutino, and Centaur HH-distributions while simultaneously predicting a large enough scattering TNO population to act as the sole supply of the Jupiter-Family Comets.

Keywords

Cite

@article{arxiv.1511.02896,
  title  = {OSSOS II: A Sharp Transition in the Absolute Magnitude Distribution of the Kuiper Belt's Scattering Population},
  author = {C. Shankman and J. J. Kavelaars and B. J. Gladman and M. Alexandersen and N. Kaib and J. -M. Petit and M. T. Bannister and Y. -T Chen and S. Gwyn and M. Jakubik and K. Volk},
  journal= {arXiv preprint arXiv:1511.02896},
  year   = {2016}
}