The TAOS Project: Results From Seven Years of Survey Data

TL;DR

This paper reports seven years of TAOS survey data searching for small Kuiper Belt Objects, resulting in no detections but setting upper limits on their size distribution.

Contribution

It provides the first long-term survey results for small KBOs, establishing upper limits on their abundance and size distribution slope.

Findings

No occultation events detected in seven years

Set 95% confidence upper limits on KBO size distribution

Constrained the slope of the faint end of the KBO size distribution

Abstract

The Taiwanese-American Occultation Survey (TAOS) aims to detect serendipitous occultations of stars by small (about 1 km diameter) objects in the Kuiper Belt and beyond. Such events are very rare (<0.001 events per star per year) and short in duration (about 200 ms), so many stars must be monitored at a high readout cadence. TAOS monitors typically around 500 stars simultaneously at a 5 Hz readout cadence with four telescopes located at Lulin Observatory in central Taiwan. In this paper, we report the results of the search for small Kuiper Belt Objects (KBOs) in seven years of data. No occultation events were found, resulting in a 95% c.l. upper limit on the slope of the faint end of the KBO size distribution of q = 3.34 to 3.82, depending on the surface density at the break in the size distribution at a diameter of about 90 km.