Séminaire Univers / |
| « Probing the late time Universe with CMB secondaries » |
|
Aleksandra Kusiak |
| The Cosmic Microwave Background (CMB) data not only provide powerful constraints on the early Universe physics, but also information from the late Universe, as the CMB photons interact with matter while propagating through cosmic time. One of such powerful probes of late-time physics is the Sunyaev-Zel’dovich (SZ) Effect—inverse-Compton scattering of the CMB photons off free electrons in galaxies and clusters. Its two main constituents are the kinematic SZ effect (kSZ), where electrons have a non-zero line-of-sight (LOS) velocity and which probes the electron momentum, and the thermal SZ effect (tSZ), where electrons have high temperatures, and which probes the electron integrated pressure. Another such effect is the CMB gravitational lensing which occurs when the CMB photons are deflected by the gravitational potential of matter along their path and which maps the integrated matter distribution. In this talk, I will present ongoing work on SZ–LSS cross-correlations with the Atacama Cosmology Telescope (ACT) data, including the tSZ x galaxies to constrain gas pressure profile, as well as the projected-fields kSZ to probe gas density. I will also show the first lensing detected with new Simons Observatory (SO) telescope which had its first light earlier this year, and highlight its exciting potential for future studies. |
|
jeudi 9 octobre 2025 - 14:00 Salle Planck Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |