Hongwan Liu (Princeton/NYU):
Nashwan Sabti (King's College):
Title: New Roads to the Small-Scale Universe: Measurements of the Clustering of Matter with the High-Redshift UV Galaxy Luminosity Function
Abstract: The epochs of cosmic dawn and reionisation present promising avenues for understanding the role of dark matter (DM) in our cosmos. The first galaxies that populated our Universe during these eras resided in DM halos that were much less massive than their counterparts today. Consequently, observations of such galaxies can provide us with a handle on the clustering properties of DM in an otherwise inaccessible regime. In this talk, I will show how high-redshift UV galaxy luminosity-function (UV LF) data from the Hubble Space Telescope can be used to study the clustering of DM at small scales. In particular, I will show how it provides a measurement of the matter power spectrum at wavenumbers 0.5 Mpc^-1 < k < 10 Mpc^-1, after marginalising over astrophysical parameters. This measurement covers the uncharted redshift range 4 <= z <= 10 and reaches scales beyond those covered by Cosmic Microwave Background and Large-Scale Structure observations.