X-ray variability with WFXT: AGNs, transients and more

TL;DR

The WFXT mission is designed to rapidly survey large sky areas, enabling detailed studies of X-ray variability in thousands of AGNs and detection of rare transient phenomena across cosmological distances.

Contribution

This paper estimates WFXT's capabilities in the time domain, highlighting its potential to study X-ray variability and transient sources in unprecedented detail.

Findings

WFXT can monitor thousands of AGNs for variability.

It can detect rare transients like Tidal Disruption Events and faint GRBs.

WFXT's surveys will explore X-ray populations over large cosmological volumes.

Abstract

The Wide Field X-ray Telescope (WFXT) is a proposed mission with a high survey speed, due to the combination of large field of view (FOV) and effective area, i.e. grasp, and sharp PSF across the whole FOV. These characteristics make it suitable to detect a large number of variable and transient X-ray sources during its operating lifetime. Here we present estimates of the WFXT capabilities in the time domain, allowing to study the variability of thousand of AGNs with significant detail, as well as to constrain the rates and properties of hundreds of distant, faint and/or rare objects such as X-ray Flashes/faint GRBs, Tidal Disruption Events, ULXs, Type-I bursts etc. The planned WFXT extragalactic surveys will thus allow to trace variable and transient X-ray populations over large cosmological volumes.