Synergies between the Cherenkov Telescope Array and THESEUS

TL;DR

This paper discusses the complementary capabilities of the Cherenkov Telescope Array (CTA) and the THESEUS mission in advancing gamma-ray and X-ray transient astronomy through their combined observational strengths.

Contribution

It highlights the potential scientific synergies between CTA and THESEUS, emphasizing how THESEUS's X-ray monitoring can enhance CTA's gamma-ray transient observations.

Findings

CTA's rapid response improves transient detection

THESEUS provides precise localization for CTA follow-ups

Combined observations will expand understanding of high-energy transients

Abstract

The Cherenkov Telescope Array (CTA) is designed to be the next major observatory operating in the Very High Energy (VHE, $\gtrsim 100$ GeV) gamma-ray band. It will build on the imaging atmospheric Cherenkov technique but will go much further in terms of performance than current instruments. Its sensitivity at short timescales and the rapid repointing system will make CTA a perfect facility to observe the gamma-ray transient sky. In this respect, the synergies between CTA and other multi-wavelength and multi-messenger facilities are expected to further enhance CTA's scientific scope. Thanks to its characteristics, THESEUS will perform an unprecedented monitoring of the X-ray variable sky, detecting, localising, and identifying transients. It will provide external triggers and accurate location for the CTA follow-up of transients, and their broadband characterisation, playing a key role for CTA after the next decade.