Presentation #315.07 in the session Cosmology.
The ROLSES instrument is to be delivered on the nearside of the lunar surface by NASA’s CLPS program this Summer of 2023, and to observe in the low radio frequency range. I will discuss our studies in preparation for employing these observations to both characterize the beam-weighted sky and, in combination with e.g. our constraints from PSP/FIELDS data on the radio foreground, analyze the electromagnetic properties of the lunar subsurface via its effects on the antenna beam. I will also present the latest status of our data analysis pipeline for the extraction of the global 21-cm signal from challenging systematics, such as the beam-weighted foreground, and its application to forecast data analyses for LuSEE-Night. The latter is to also be delivered by the CLPS program to the lunar surface, but to the far side, in late 2025 or early 2026. This experiment will benefit from standalone operations through the lunar night, without the electromagnetic interference of an operating lander, and free of radio frequency interference from Earth. Our ROLSES studies should also effectively feed into the forecasting, and then observational, analyses for LuSEE-Night. To achieve the long-term goal of constraining the key early Universe epochs of the Dark Ages and Cosmic Dawn, it is necessary to robustly model the sky to the error level necessary to recover the orders-of-magnitude smaller absorption troughs of interest, as I will also discuss based on a recent analysis from our group. ROLSES and LuSEE-Night should provide the first critical steps of an observational strategy from the Moon that promises rich opportunities in the era of NASA’s Artemis missions and CLPS program.