BICEP2 / Keck Array VII: Matrix based E/B Separation applied to BICEP2 and the Keck Array
Abstract
A linear polarization field on the sphere can be uniquely decomposed into an E-mode and a B-mode component. These two components are analytically defined in terms of spin-2 spherical harmonics. Maps that contain filtered modes on a partial sky can also be decomposed into E-mode and B-mode components. However, the lack of full sky information prevents orthogonally separating these components using spherical harmonics. In this paper, we present a technique for decomposing an incomplete map into E and B-mode components using E and B eigenmodes of the pixel covariance in the observed map. This method is found to orthogonally define E and B in the presence of both partial sky coverage and spatial filtering. This method has been applied to the BICEP2 and the Keck Array maps and results in reducing E to B leakage from LCDM E-modes to a level corresponding to a tensor-to-scalar ratio of .
Cite
@article{arxiv.1603.05976,
title = {BICEP2 / Keck Array VII: Matrix based E/B Separation applied to BICEP2 and the Keck Array},
author = {Keck Array and BICEP2 Collaborations and : and P. Ade and Z. Ahmed and R. W. Aikin and K. D. Alexander and D. Barkats and S. J. Benton and C. A. Bischoff and J. J. Bock and R. Bowens-Rubin and J. A. Brevik and I. Buder and E. Bullock and V. Buza and J. Connors and B. P. Crill and L. Duband and C. Dvorkin and J. P. Filippini and S. Fliescher and J. Grayson and M. Halpern and S. Harrison and S. R. Hildebrandt and G. C. Hilton and H. Hui and K. D. Irwin and J. Kang and K. S. Karkare and E. Karpel and J. P. Kaufman and B. G. Keating and S. Kefeli and S. A. Kernasovskiy and J. Kovac and C. L. Kuo and E. M. Leitch and M. Lueker and K. G. Megerian and T. Namikawa and C. B. Netterfield and H. T. Nguyen and R. O'Brient and R. W. and A. Orlando and C. Pryke and S. Richter and R. Schwarz and C. D. Sheehy and Z. K. Staniszewski and B. Steinbach and R. V. Sudiwala and G. P. Teply and K. L. Thompson and J. E. Tolan and C. Tucker and A. D. Turner and A. G. Vieregg and A. C. Weber and D. V. Wiebe and J. Willmert and C. L. Wong and W. L. K. Wu and K. W. Yoon},
journal= {arXiv preprint arXiv:1603.05976},
year = {2016}
}
Comments
21 pages, 23 figures, minor updates to reflect accepted version