ITC Seminar - Julian Munoz (Harvard Physics)


Tuesday, February 11, 2020, 12:00pm to 1:00pm



"Learning Cosmology with the First Stars"

I will describe how upcoming 21-cm measurements during cosmic dawn will provide a trove of new cosmological information. This era saw the formation of the first stars, which excited neutral hydrogen and allowed it to absorb 21-cm photons from the CMB. The timing of this signal carries information on the abundance of the small mini-halos that hosted the first stars, allowing us to probe the matter power spectrum at smaller scales than currently possible. Moreover, I will describe how the relative velocities between dark matter and baryons are imprinted onto the 21-cm power spectrum during cosmic dawn, resulting in robust velocity-induced acoustic oscillations (VAOs). These act as a new standard ruler at z=20, opening up searches for the early dark energy argued to resolve the H0 tension.

See also: Seminars, 2019 - 20