Kuiper Belt Object Occultations: Expected Rates, False Positives, and Survey Design

TL;DR

This paper develops a new method to evaluate occultation rates and false positives in Kuiper Belt Object surveys, providing insights into optimal survey design and detection thresholds for identifying genuine KBO occultations.

Contribution

It introduces a novel artificial scintillation noise model and analyzes survey parameters to optimize detection of Kuiper Belt Object occultations.

Findings

Diffraction-dominated occultations are critically sampled at 2 Fsu^{-1}.

Maximum occultation detection occurs at solar opposition.

Genuine KBO occultations are rare, requiring >7-8 sigma detection thresholds.

Abstract

A novel method of generating artificial scintillation noise is developed and used to evaluate occultation rates and false positive rates for surveys probing the Kuiper Belt with the method of serendipitous stellar occultations. A thorough examination of survey design shows that: (1) diffraction-dominated occultations are critically (Nyquist) sampled at a rate of 2 Fsu^{-1}, corresponding to 40 s^{-1} for objects at 40 AU, (2) occultation detection rates are maximized when targets are observed at solar opposition, (3) Main Belt Asteroids will produce occultations lightcurves identical to those of Kuiper Belt Objects if target stars are observed at solar elongations of: 116 deg < epsilon < 125 deg, or 131 deg < epsilon < 141 deg, and (4) genuine KBO occultations are likely to be so rare that a detection threshold of >7-8 sigma should be adopted to ensure that viable candidate events can be disentangled from false positives.