Colloque national CMB-France #6

Session

CMB analysis and results

18 déc. 2024, 16:30

Institut Henri Poincaré

3. Setting requirements on out-of-band rejection for next-generation CMB experiments.

Louise MOUSSET (LPENS)

18/12/2024 16:30

Next-generation CMB experiments have very stringent constraints to achieve the required sensitivity to target polarization B-modes. In this work, we intend to set constraints on out-of-band rejection level and derive requirements on the telescope filtering scheme. We follow a global approach, taking into account the impact on detector noise, on thermal balance and on thermal stability. This...

17. Searching for Cosmological Collider in the Planck CMB Data

Wuhyun sohn (APC / CNRS)

18/12/2024 16:50

New heavy particles during inflation can leave imprints in the primordial perturbations and subsequently in the observed CMB anisotropies. This remarkable detection channel allows us to probe new physics at extremely high energies. I present our recent work on the first extensive search for cosmological collider signals with the CMB data. We utilise the publicly available CMB bispectrum...

25. Latest/last constraints on the Epoch of Reionization from Planck

Stéphane ILIC (IJCLab)

18/12/2024 17:10

The cosmic microwave background provides a crucial window into the early universe's evolution, offering insights into the epoch of reionization (EoR). In this talk, I will present new constraints on the reionization history derived from the final Planck data release (Public Data Release 4, PR4). Leveraging the enhanced sensitivity and reduced systematic uncertainties of the PR4 data, we...

2. Non-Gaussian effects in CMB lensing maximum a posteriori methods

Omar Darwish (University of Geneva)

18/12/2024 17:30

We will discuss non-Gaussian effects in CMB lensing maximum a posteriori methods (MAP) coming from the large-scale structure bispectrum and extragalactic foregrounds emission. We will show how MAP methods naturally mitigate biases that are relevant for standard CMB lensing estimators, both in auto and cross-correlation analyses. This will not be relevant only for CMB-S4, for which MAP methods...

5. Optimal lensing estimators for future CMB surveys

Louis Legrand (DAMTP, University of Cambridge)

18/12/2024 17:50

Gravitational lensing of the Cosmic Microwave Background (CMB) will soon be reconstructed with unprecedented precision, driven by deep polarisation maps from upcoming experiments like SPT-3G, the Simons Observatory, and CMB-S4. Reconstructing and subtracting the lensed B modes of polarisation is crucial to uncover the primordial B modes from inflation. In this talk, I will introduce an optimal...

14. A flexible parameterization to test early physics solutions to the Hubble tension with future CMB data

Raphaël Kou (University of Sussex)

18/12/2024 18:10

The discrepancy between local measurements of the Hubble constant and inferences from CMB and galaxy clustering data, known as the "Hubble tension", has motivated numerous models introducing additional components active before recombination. While many such models have been proposed, none are currently strongly favoured by data. This highlights the critical role of upcoming CMB experiments,...