Systematics-insensitive Periodogram for finding periods in TESS observations of long-period rotators

TL;DR

This paper introduces a Python tool designed to accurately detect long-period stellar rotation signals in TESS data, especially for targets observed continuously in the CVZ, by reducing instrument systematics.

Contribution

The paper presents a new systematics-insensitive periodogram method tailored for long-period rotation detection in TESS CVZ observations.

Findings

Effective in extracting long rotation periods from TESS CVZ data

Mitigates instrument systematics in period detection

Provides a user-friendly Python package

Abstract

NASA's TESS mission \citep{tess} has produced high precision photometry of millions of stars to the community. The majority of TESS observations have a duration of $\approx$27 days, corresponding to a single observation during a TESS sector. A small subset of TESS targets are observed for multiple sectors, with approximately 1-2\% of targets falling in the Continuous Viewing Zone (CVZ) during the prime mission \citep{yield}, where targets are observed continuously for a year. These targets are highly valuable for extracting long period rotation rates, which can be linked to stellar ages. We present a pip installable Python tool for extracting long period rotation rates in the TESS CVZ, while simultaneously mitigating instrument systematics.