Galaxy clustering at cosmic dawn from JWST/NIRCam observations to redshift z∼11

Abstract

We report measurements of the galaxy two-point correlation function at cosmic dawn, using photometrically selected sources from the JWST Advanced Deep Extragalactic Survey (JADES). The JWST/NIRCam data set comprises approximately Ng ≃ 7000 photometrically selected Lyman Break Galaxies (LBGs), spanning in the redshift range 5 ≤ z < 11. The primary objective of this study is to extend clustering measurements beyond redshift z > 10, finding a galaxy bias b = 9.6 ± 1.7 for the sample at z = 10.6. The result suggests that the observed sources are hosted by dark matter haloes of approximately Mh ∼ 1010.6 M, in broad agreement with theoretical and numerical modelling of early galaxy formation during the epoch of reionization. Furthermore, the JWST JADES data set enables an unprecedented investigation of clustering of dwarf galaxies two orders of magnitude fainter than the characteristic L∗ luminosity (i.e. with MF200W ≃ −15.8) during the late stages of the epoch of reionization at z ∼ 6. By analysing clustering as a function of luminosity, we find that b(MF200W) aligns with previous results for brighter galaxies and then decreases with MF200W, as theoretically expected for fainter candidates. These initial results demonstrate the potential for further quantitative characterization of the interplay between assembly of dark matter and light during cosmic dawn that the growing samples of JWST observations are enabling.