The Need for Ultra High Resolution X-ray Imaging

TL;DR

This paper advocates for the development of ultra high resolution X-ray imaging to unlock new astrophysical insights, highlighting technological challenges and proposing the Accretion Explorer mission concept.

Contribution

It identifies the scientific need for milliarcsecond to microarcsecond X-ray imaging and discusses potential mission architectures like the dispersed aperture X-ray interferometer.

Findings

High-resolution X-ray imaging is essential for key astrophysical discoveries.

Current X-ray imaging capabilities lag behind other wavelengths.

The proposed Accretion Explorer could achieve the desired resolution.

Abstract

This paper discusses the broad science case for obtaining milliarcsecond to microarcsecond astronomical imaging resolution in the soft to medium-energy X-ray band (~0.5 to ~8 keV). Astronomy across much of the electromagnetic spectrum has been fundamentally transformed with a rapid increase in ground-based and space-based capabilities to examine celestial objects on small scales that relate directly to their relevant physical processes. X-ray imaging capabilities, however, have fallen far behind observations at longer wavelengths. As such, without decisive advances in X-ray imaging, we will be unable to uncover key phenomena on the smallest astrophysical scales, leaving entire classes of high-energy discoveries beyond our reach. Here we describe several science goals for which high quality X-ray imaging is crucial and the status of some current technologies or mission concepts that would be required for these advances. In particular, we discuss the Accretion Explorer, a mission architecture under current study for a dispersed aperture X-ray interferometer.