Wide-field investigation of the Kuiper Belt

• Main Author: Trujillo, Chadwick Aaron
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2000
• Subjects: Astrophysics
• ISBN: 0599834838; 9780599834835

Two wide-field surveys have been conducted for Kuiper Belt Objects (KBOs) and Centaurs using the largest close-packed CCD Mosaic cameras in the world. The first is a wide-field ecliptic survey of 157 square degrees to limiting red magnitude 21.1, responsible for the discovery of 3 KBOs and 1 Centaur. The second is a much deeper survey of 76 square degrees to limiting red magnitude 23.7, which found 86 KBOs. Data were analysed using the same software methods, and a maximum-likelihood simulation was used to debias the observations in a consistent manner. Fundamental quantities describing the Kuiper Belt are derived from these data: size distribution, inclination distribution, radial extent, and total mass. We find that the KBOs follow a differential power law size distribution with index q = 3.8 (+0.3, −0.4; 1σ = 68.27% confidence), consistent with the crushed rock size distributions measured in hypervelocity impact experiments. In addition, the debiased inclinations of the Classical KBOs are consistent with a thick Gaussian distribution with half-width 20 (+8, −2; 1σ) degrees. The Scattered KBOs are consistent with a Gaussian model with half-width 11 (+6, −3; 1σ) degrees, with modal inclination 20 (+9, −4; 1σ) degrees. The inclination measurements indicate that the KBOs are in a highly erosive state, with velocity dispersions of 1 to 2 kilometers per second. Strong evidence is presented for a truncation of the Classical KBOs at heliocentric distances beyond 50 AU. The total number and mass of the Scattered KBOs is about 3 times larger than that of the Classical KBOs, with a combined mass from the two populations of about 0.3 Earth masses.