A Beginner’s Guide to Line Intensity Mapping Power Spectra

Abstract

Line intensity mapping (LIM) is an emerging technique in measuring galaxy evolution and the large-scale structure of the universe. LIM surveys measure the cumulative emission from all galaxies emitting a given line at a particular redshift, which trace the distribution of dark matter throughout the universe. In this proceeding, we provide an introduction to LIM modeling, focusing on power spectrum calculation. Beyond these calculations, we describe how these power spectra may be used to constrain properties of galaxy evolution and large-scale structure cosmology. Throughout, we use the anticipated EXCLAIM signal of ionized carbon ([CII]) at redshift z=3 as a case study. Our goal is to provide a starting point to non-experts, e.g. upper-level undergraduate and graduate students familiar with the basics of cosmology, with the tools necessary to understand the literature and generate LIM power spectrum models themselves, while also describing a wide array of literature for continued studies.

SPT-SLIM Calibrator Box

“…LIM: Line intensity mapping (LIM) is an observational technique in which an atomic or molecular line is observed spectroscopically across a range of redshifts, tracing the large-scale structure in the universe [3].…”

“…LIM is a tool that can tell us more about the structural growth of the universe as a result of the measurement of distributions of matter at large scales, as well as the history of cosmic star formation [3].…”