# Dark Sectors of Astroparticle Physics (AstroDark-2021): Axions, Neutrinos, Black Holes and Gravitational Waves

7-10 December 2021
Online
Asia/Tokyo timezone

## A Measurement of Small-scale Structure with Hubble Legacy Fields

7 Dec 2021, 11:20
18m
Online

#### Online

Details are notified to registrants.

### Speaker

Julian B. Munoz (Harvard-Smithsonian Center for Astrophysics)

### Description

I will describe a new measurement of the small-scale matter power spectrum using UV luminosity-functions (UVLFs) from the Hubble Space Telescope. These data trace the abundance of the first galaxies forming during the epoch of reionization. Since the first galaxies were much less massive than their counterparts today, they provide us with a handle on the clustering of dark matter at smaller scales. I will present the public code GALLUMI, which is built to efficiently marginalize over astrophysical uncertainties and obtain cosmological constraints. Our analysis is able to measure small-scale matter fluctuations at $k=0.5-10 \mathrm{Mpc}^{-1}$ and $z=4-10$ to roughly 30\% precision. This measurement sheds light onto the nature of dark matter in a currently uncharted range of scales and redshifts.

### Primary authors

Julian B. Munoz (Harvard-Smithsonian Center for Astrophysics)