On the detection of the tensor-to-scalar ratio r using the CMB B-modes
Agns Fert In collaboration with: Julien Peloton, Julien Grain, Radek Stompor Based on: arxiv: CMB B-modes caused by tensor perturbations and lensing of E-modes
(Q,U) maps E and B modes power spectra Tensor-to-scalar ratio r CMB B-modes at low-l probe the primordial Universe
Lensing B modes: 1st direct detection by Polarbear (arxiv: ) Primordial B modes: r 0.038 r > r > Pure method r > 0.11 r > r > Foreground impact on the detection of r
Remove the first bin: 2 < l < 20 Example of satellite xp Small scale xp Telescopes array Satellite mission Mode counting r > 0.04 r > r > Pure method r > 0.11 r > r > TO TAKE AWAY The pure estimation of B modes is awesome
The mode-counting approach is enough to state on optimal sky coverage The pure method is mandatory to perform realistic forecasts on r detection Potential future satellite mission: r 10-3 Stage 4 array of telescope: r 10-2 Current ground-based or balloon borne: r 10-1 Side personal note: the CMB TB and EB correlations hold information on fundamental physics (e.g. : parity breaking, birefringence, primordial magnetic field) From NASA Effect of binning Optimised window functions SNR on r Small scale Array of telescopes