Simultaneous observations of the northern TESS sectors by the Zwicky Transient Facility

TL;DR

This paper describes the Zwicky Transient Facility's nightly observations of all 13 northern TESS sectors in 2019-2020, providing valuable time-domain data for variability studies and TESS field analysis.

Contribution

It details the ZTF survey strategy for observing TESS sectors, including data products and observational parameters, enhancing the TESS data with ground-based optical observations.

Findings

ZTF observed all 13 northern TESS sectors nightly in 2019-2020.

Data includes $g$ and $r$ band images with a limiting magnitude of ~20.6.

Multiple data products are released, including alerts and light curves.

Abstract

The Zwicky Transient Facility (ZTF) is conducting a nightly public survey of all 13 TESS northern sectors in 2019-2020. ZTF will observe the portions of the current TESS sectors visible from Palomar Observatory each night. Each ZTF pointing will have one exposure each with $g$ and $r$ filters, totaling two images per night. ZTF is also making additional nightly $g$- and $r$-band observations of denser stellar regions (e.g. near the Galactic Plane) to better facilitate variability studies of Galactic objects. The limiting magnitude of the ZTF observations is $\approx$20.6 and ZTF saturates at magnitude $\approx$13. ZTF will release data from TESS fields in three forms: nightly alerts distributed by established ZTF brokers, nightly alerts converted to JSON format are distributed via ZTF's bucket on Google Cloud as a tarball, and monthly photometric light curves also distributed via Google Cloud.