Planck constraints on Cosmic Birefringence and its cross-correlation with the CMB

• DOI: 10.48550/arxiv.2401.11973
• Publication Date: 2024-01-01
• Authors: G. Zagatti; M. Bortolami; A. Gruppuso; P. Natoli; L. Pagano; Giulio Fabbian
• Keywords: Cosmic variance

Cosmic birefringence is the in-vacuo, frequency independent rotation of polarization plane linearly polarized radiation, induced by a parity-violating term in electromagnetic Lagrangian. We implement an harmonic estimator for field that only relies on CMB E to B mode cross-correlation, thus suppressing effect cosmic variance from temperature field. derive constraints Planck public releases 3 and 4, revealing power spectrum consistent with zero at about $2\sigma$ up multipole $L=1500$. Moreover, we find cross-correlations T-, E- B-fields are also well compatible null. The latter two provided here first time