English

B-mode CMB Polarization from Patchy Screening during Reionization

Cosmology and Nongalactic Astrophysics 2009-07-30 v2

Abstract

B-modes in CMB polarization from patchy reionization arise from two effects: generation of polarization from scattering of quadrupole moments by reionization bubbles, and fluctuations in the screening of E-modes from recombination. The scattering contribution has been studied previously, but the screening contribution has not yet been calculated. We show that on scales smaller than the acoustic scale (l>300), the B-mode power from screening is larger than the B-mode power from scattering. The ratio approaches a constant ~2.5 below the damping scale (l>2000). On degree scales relevant for gravitational waves (l<100), screening B-modes have a white noise tail and are subdominant to the scattering effect. These results are robust to uncertainties in the modeling of patchy reionization.

Cite

@article{arxiv.0902.4413,
  title  = {B-mode CMB Polarization from Patchy Screening during Reionization},
  author = {Cora Dvorkin and Wayne Hu and Kendrick M. Smith},
  journal= {arXiv preprint arXiv:0902.4413},
  year   = {2009}
}

Comments

4 pages, 1 figure; minor changes matching PRD published version

R2 v1 2026-06-21T12:15:32.960Z