Yun-Ting Cheng (JPL/Caltech): "Mapping Lines and PAHs Across Cosmic Time in the Infrared Spectral-Photometry Era"

Line intensity mapping (LIM) probes the aggregate emission of spectral lines from all sources without individual detections. Through the wavelength-redshift relation, one can map the line-of-sight evolution of line emission that traces the underlying large-scale structure in spectral-imaging surveys. The ongoing near-infrared all-sky survey SPHEREx, and the proposed far-infrared mission PRIMA, are both well-suited to probing LIM signals from multiple lines across cosmic time. In addition, polycyclic aromatic hydrocarbons (PAHs) are among the most prominent features in infrared galaxy spectra. We have recently developed a technique to extend the LIM formalism to broad spectral features such as PAHs, and have demonstrated the prospect of mapping aggregate PAH emission in three dimensions with SPHEREx and PRIMA. In this talk, I will first introduce the intensity mapping technique, then discuss the unique opportunities enabled by conducting line and PAH intensity mapping with SPHEREx and PRIMA with our latest forecasts.