A Periodogram of Every Kepler Target and a Common Artifact at ~80 Minutes

TL;DR

This paper provides a comprehensive archive of Kepler mission power spectra, enabling detection of stellar and planetary signals, and identifies a common instrumental artifact at approximately 80 minutes.

Contribution

It introduces a large, publicly available archive of Kepler power spectra and details the detection of a recurring instrumental artifact at ~80 minutes.

Findings

A new archive of over 2.5 million Kepler periodograms is available.

Identification of a common instrumental artifact at ~80 minutes.

Normalized and combined spectra reveal instrumental modes.

Abstract

Studying photometric time series in the frequency domain can serve as a means of detecting rotational modulations, measuring asteroseismic modes and even detecting short-period transiting planets. To our knowledge, there is no prior archive of the NASA Kepler Mission's power spectra and so we present one here to aid the community in searching for such effects. Using DR25 PDC long-cadence Kepler photometry, 2,594,616 individual periodograms are computed using Welch's method with a Nuttall window, where we provide a unique periododogram for each quarter (up to 16) of each star (196,791 in total). Additionally, we normalize the periodograms in the high-frequency end and combine them into channel- and quarter-averaged power spectra to track common instrumental modes occurring onboard the telescope, with a particularly notable feature at ~80 minutes (~200 $\mu$Hz) observed.