Pipeline for the Detection of Serendipitous Stellar Occultations by Kuiper Belt Objects with the Colibri Fast-Photometry Array

TL;DR

This paper presents the preliminary results of Colibri, a fast-photometry array designed to detect small Kuiper belt objects via stellar occultations, demonstrating a low false positive rate and describing the data processing pipeline and software tools.

Contribution

It introduces Colibri's data processing pipeline, software design, and methods for detecting and analyzing stellar occultations by Kuiper belt objects.

Findings

Detected one false positive event in 4000 star hours

False positive rate matches simulation predictions

No Kuiper belt objects detected in preliminary trials

Abstract

We report results from the preliminary trials of Colibri, a dedicated fast-photometry array for the detection of small Kuiper belt objects through serendipitous stellar occultations. Colibri's novel data processing pipeline analyzed 4000 star hours with two overlapping-field EMCCD cameras, detecting no Kuiper belt objects and one false positive occultation event in a high ecliptic latitude field. No occultations would be expected at these latitudes, allowing these results to provide a control sample for the upcoming main Colibri campaign. The empirical false positive rate found by the processing pipeline is consistent with the 0.002% simulation-determined false positive rate. We also describe Colibri's software design, kernel sets for modeling stellar occultations, and method for retrieving occultation parameters from noisy diffraction curves. Colibri's main campaign will begin in mid-2018, operating at a 40 Hz sampling rate.