Active Galaxy Science with the Line Emission Mapper: The Case for High-Resolution Soft X-ray Spectroscopy

TL;DR

This paper advocates for the Line Emission Mapper (LEM), a proposed soft X-ray observatory with high spectral resolution and wide field imaging, to advance active galactic nuclei research and galaxy evolution studies.

Contribution

It introduces the LEM mission concept, emphasizing its potential to enable groundbreaking AGN science through high-resolution soft X-ray spectroscopy and wide-field imaging.

Findings

Enables detailed AGN studies in soft X-ray band

Supports galaxy evolution research with high-resolution data

Facilitates vital discoveries through all-sky surveys

Abstract

This white paper discusses the breadth of science related to active galactic nuclei (AGN) and associated phenomena to be enabled by a mission with microcalorimeter energy resolution in the soft X-ray band, a large collecting area, and wide-field imaging. Such a mission, the Line Emission Mapper (LEM), has been proposed to NASA's 2023 Astrophysics Probe Explorer call. While the science pillars of the PI-led part of the mission focus on galaxy evolution, the PI-led LEM All-Sky Survey (LASS) and General Observer/Investigator opportunities will enable vital discoveries for AGN science in the critical soft X-ray band.