Work

Line-intensity mapping

Year: 2026

Type: article

Abstract: Line-Intensity Mapping (LIM) has emerged as a powerful technique for studying large-scale structure and the high-redshift universe, enabling three-dimensional maps of line emission across vast cosmological volumes. In this review, we summarize the LIM framework, its key scientific goals, and its future prospects. We describe the landscape of emission line tracers, theoretical modeling approaches, anticipated signals, and data-analysis methodologies. We also discuss experimental challenges, particularly those posed by astrophysical foregrounds, and review possible mitigation strategies. Further, we highlight a range of cross-correlation science cases, linking LIM with other cosmological surveys. Finally, we summarize current and upcoming experiments and early results, including recent first detections, while outlining the outlook for future discoveries. Specifically, LIM may offer new insights into galaxy formation and evolution and cosmology, while revealing the Epoch of Reionization, Cosmic Dawn, and possibly the Cosmic Dark Ages. LIM enables cosmological measurements that complement other probes and provide unique access to the high-redshift universe, potentially shedding light on dark matter, dark energy, and cosmic inflation.

Source: Physics Reports

DOI: 10.1016/j.physrep.2026.09.003

Authors: Tzu-Ching Chang, Adam Lidz

Institutions: California Institute of Technology, Jet Propulsion Laboratory, University of Pennsylvania

Language: English

Topic: Galaxies: Formation, Evolution, Phenomena

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $6,240

Funders: National Science Foundation, National Aeronautics and Space Administration, Jet Propulsion Laboratory