The KELT Follow-Up Network and Transit False Positive Catalog: Pre-vetted False Positives for TESS

TL;DR

This paper presents a catalog of 1,128 bright stars with transit-like signals identified as false positives through follow-up observations, aiding future exoplanet surveys like TESS in reducing redundant efforts.

Contribution

It provides the first all-sky catalog of astrophysical false positives from KELT data, enhancing the efficiency of exoplanet validation for TESS and other surveys.

Findings

Over 1,600 follow-ups conducted since 2011

More than 20 planets discovered by KELT-FUN

Catalog of 1,128 false positives published

Abstract

The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey for transiting planets orbiting bright stars for over ten years. The KELT images have a pixel scale of ~23"/pixel---very similar to that of NASA's Transiting Exoplanet Survey Satellite (TESS)---as well as a large point spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3'. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with higher spatial resolution, cadence, and photometric precision than the KELT telescopes, as well as spectroscopic observations of the candidate host stars. The KELT-FUN team has followed-up over 1,600 planet candidates since 2011, resulting in more than 20 planet discoveries. Excluding ~450 false alarms of non-astrophysical origin (i.e., instrumental noise or systematics), we present an all-sky catalog of the 1,128 bright stars (6<V<10) that show transit-like features in the KELT light curves, but which were subsequently determined to be astrophysical false positives (FPs) after photometric and/or spectroscopic follow-up observations. The KELT-FUN team continues to pursue KELT and other planet candidates and will eventually follow up certain classes of TESS candidates. The KELT FP catalog will help minimize the duplication of follow-up observations by current and future transit surveys such as TESS.