COSMOS-Web: An Overview of the JWST Cosmic Origins Survey

TLDR

COSMOS-Web builds on the extensive multiwavelength data available in the COSMOS field. This paper outlines the design, implementation, and scientific objectives of the 255‑hour JWST COSMOS‑Web survey, aiming to map reionization, identify rare quiescent galaxies, and study the stellar mass–halo mass relation up to z≈2.5, while anticipating broad legacy science. COSMOS‑Web will conduct contiguous 0.54 deg² NIRCam imaging in four filters to 5σ depths of ~27.5–28.2 mag and 0.19 deg² MIRI imaging in F770W to ~25.3–26.0 mag, using these data to pursue the outlined science.

Abstract

We present the survey design, implementation, and outlook for COSMOS-Web, a 255 hour treasury program conducted by the James Webb Space Telescope in its first cycle of observations. COSMOS-Web is a contiguous 0.54 deg2 NIRCam imaging survey in four filters (F115W, F150W, F277W, and F444W) that will reach 5σ point source depths ranging ∼27.5-28.2 magnitudes. In parallel, we will obtain 0.19 deg2 of MIRI imaging in one filter (F770W) reaching 5σ point source depths of ∼25.3-26.0 magnitudes. COSMOS-Web will build on the rich heritage of multiwavelength observations and data products available in the COSMOS field. The design of COSMOS-Web is motivated by three primary science goals: (1) to discover thousands of galaxies in the Epoch of Reionization (6<z<11) and map reionization's spatial distribution, environments, and drivers on scales sufficiently large to mitigate cosmic variance, (2) to identify hundreds of rare quiescent galaxies at z>4 and place constraints on the formation of the Universe's most massive galaxies (M⋆>1010\,M⊙), and (3) directly measure the evolution of the stellar mass to halo mass relation using weak gravitational lensing out to z∼2.5 and measure its variance with galaxies' star formation histories and morphologies. In addition, we anticipate COSMOS-Web's legacy value to reach far beyond these scientific goals, touching many other areas of astrophysics, such as the identification of the first direct collapse black hole candidates, ultracool sub-dwarf stars in the Galactic halo, and possibly the identification of z>10 pair-instability supernovae. In this paper we provide an overview of the survey's key measurements, specifications, goals, and prospects for new discovery.