CMB Polarization Systematics Due to Beam Asymmetry: Impact on Cosmological Birefringence - Astrophysics > Cosmology and Nongalactic AstrophysicsReport as inadecuate




CMB Polarization Systematics Due to Beam Asymmetry: Impact on Cosmological Birefringence - Astrophysics > Cosmology and Nongalactic Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: The standard cosmological model is assumed to respect parity symmetry. Underthis assumption the cross-correlations of the CMB-s temperature anisotropy and`gradient-like polarization, with the `curl-like polarization identicallyvanish over the full sky. However, extensions of the standard model which allowfor light scalar field or axion coupling to the electromagnetic field, orcoupling to the Riemann gravitational field-strength, as well as othermodifications of field theories, may induce a rotation of the CMB polarizationplane on cosmological scales and manifest itself as nonvanishing TB and EBcross-correlations. Recently, the degree of parity violation reflected inpolarization rotation was constrained using data from BOOMERANG, WMAP andQUAD. Forecasts have been made for near-future experiments e.g. PLANCK tofurther constrain parity- and Lorentz-violating terms in the fundamentalinteractions of nature. Here we consider a real-world effect induced by a classof telescope beam systematics which can mimic the rotation of polarizationplane or otherwise induce nonvanishing TB and EB correlations. In particular,adopting the viewpoint that the primary target of future experiments will bethe inflationary B-mode signal, we assume the beam-systematics of the upcomingPLANCK and POLARBEAR experiments are optimized towards this goal, and explorethe implications of the allowed levels of beam systematics on the resultingprecision of polarization-rotation measurements.



Author: N.J. Miller, M. Shimon, B.G. Keating

Source: https://arxiv.org/







Related documents