Séminaire Univers / |
| « Precision cosmology with voids in the final BOSS data » |
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Nico Hamaus |
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I will present novel cosmological constraints obtained from cosmic voids in the final BOSS DR12 dataset. They arise from the joint analysis of geometric and dynamic distortions of average void shapes (i.e., the stacked void-galaxy cross-correlation function) in redshift space. Our model uses tomographic deprojection to infer real-space void profiles and self-consistently accounts for the Alcock-Paczynski (AP) effect and redshift-space distortions (RSD) without any prior assumptions on cosmology or structure formation. It is derived from first physical principles and provides an extremely good description of the data at linear perturbation order. We validate this model with the help of mock catalogs and apply it to the final BOSS data to constrain the RSD and AP parameters f/b and D_A*H, where f is the linear growth rate, b the linear galaxy bias, D_A the comoving angular diameter distance, and H the Hubble rate. Our constraints are among the tightest of their kind to date, demonstrating the immense potential of using cosmic voids for cosmology in current and future data. |
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mardi 29 septembre 2020 - 11:15 Webinaire Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |