High-Spatial-Resolution K-Band Imaging of Select K2 Campaign Fields

TL;DR

This paper presents high-resolution K-band infrared images of K2 mission fields, enabling better vetting of exoplanet candidates and characterization of observed galaxies by resolving blending issues caused by Kepler's pixel scale.

Contribution

The study provides the first high-spatial-resolution near-infrared imaging of select K2 fields, improving target vetting and galaxy characterization capabilities.

Findings

High-resolution K-band images resolve blending issues in K2 data

Enhanced vetting of exoplanet candidates through nearby star identification

Improved galaxy size, color, and type estimation in K2 fields

Abstract

NASA's K2 mission began observing fields along the ecliptic plane in 2014. Each observing campaign lasts approximately 80 days, during which high-precision optical photometry of select astrophysical targets is collected by the Kepler spacecraft. Due to the 4 arcsec pixel scale of the Kepler photometer, significant blending between the observed targets can occur (especially in dense fields close to the Galactic plane). We undertook a program to use the Wide Field Camera (WFCAM) on the 3.8 m United Kingdom InfraRed Telescope (UKIRT) to collect high-spatial-resolution near-infrared images of targets in select K2 campaign fields, which we report here. These 0.4 arcsec resolution K-band images offer the opportunity to perform a variety of science, including vetting exoplanet candidates by identifying nearby stars blended with the target star and estimating the size, color, and type of galaxies observed by K2.