Planck intermediate results. XLIX. Parity-violation constraints from polarization data
read the original abstract
Parity violating extensions of the standard electromagnetic theory cause in vacuo rotation of the plane of polarization of propagating photons. This effect, also known as cosmic birefringence, impacts the cosmic microwave background (CMB) anisotropy angular power spectra, producing non-vanishing $T$--$B$ and $E$--$B$ correlations that are otherwise null when parity is a symmetry. Here we present new constraints on an isotropic rotation, parametrized by the angle $\alpha$, derived from Planck 2015 CMB polarization data. To increase the robustness of our analyses, we employ two complementary approaches, in harmonic space and in map space, the latter based on a peak stacking technique. The two approaches provide estimates for $\alpha$ that are in agreement within statistical uncertainties and very stable against several consistency tests. Considering the $T$--$B$ and $E$--$B$ information jointly, we find $\alpha = 0.31^{\circ} \pm 0.05^{\circ} \, ({\rm stat.})\, \pm 0.28^{\circ} \, ({\rm syst.})$ from the harmonic analysis and $\alpha = 0.35^{\circ} \pm 0.05^{\circ} \, ({\rm stat.})\, \pm 0.28^{\circ} \, ({\rm syst.})$ from the stacking approach. These constraints are compatible with no parity violation and are dominated by the systematic uncertainty in the orientation of Planck's polarization-sensitive bolometers.
This paper has not been read by Pith yet.
Forward citations
Cited by 2 Pith papers
-
Cosmic Birefringence from the Atacama Cosmology Telescope Data Release 6
Bayesian analysis of ACT DR6 CMB polarization data measures cosmic birefringence angle β = 0.215° ± 0.074° excluding zero at 2.9σ, consistent with prior WMAP and Planck results but limited by unexplained systematics.
-
CMB-S4 Science Case, Reference Design, and Project Plan
Presents the science case, reference design, and project plan for the CMB-S4 ground-based CMB experiment.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.