Abstract
Recently the second phase of Background Imaging of Cosmic Extragalactic Polarization (BICEP2) claimed a detection of the tensor-to-scalar ratio (r) of primordial fluctuation at 5ρ confidence level. If it is true, this large and measurable amplitude (r ∼- 0.2) of B-mode polarization indicates that it is possible to measure the shape of CMB B-mode polarization with future experiments. Given the current understanding of the experimental noise and foreground contamination, we forecast the precision of r and the tensor spectral index n t measurements from Planck, Spider and POLARBEAR with n t as a free parameter. We quantitatively determine the signal-to-noise of the measurement in r-n t parameter space for the three experiments. The forecasted signal-to-noise ratio of the B-mode polarization somewhat depends on n t, but strongly depends on the true value of r.
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Wang, Y., Ma, Y. Precision of future experiments measuring primordial tensor fluctuation. Sci. China Phys. Mech. Astron. 57, 1466–1470 (2014). https://doi.org/10.1007/s11433-014-5510-5
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DOI: https://doi.org/10.1007/s11433-014-5510-5