Hou, Z., Aylor, K., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. -M, Chown, R., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W. B., Follin, B., George, E. M., Halverson, N. W., Harrington, N. L., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Luong-Van, D. et al. 2018. "A Comparison of Maps and Power Spectra Determined from South Pole Telescope and Planck Data." The Astrophysical Journal, 853 3. https://doi.org/10.3847/1538-4357/aaa3ef.
We study the consistency of 150 GHz data from the South Pole Telescope (SPT) and 143 GHz data from the Planck satellite over the patch of sky covered by the SPT-SZ survey. We first visually compare the maps and find that the residuals appear consistent with noise after accounting for differences in angular resolution and filtering. We then calculate (1) the cross-spectrum between two independent halves of SPT data, (2) the cross-spectrum between two independent halves of Planck data, and (3) the cross-spectrum between SPT and Planck data. We find that the three cross-spectra are well fit (PTE = 0.30) by the null hypothesis in which both experiments have measured the same sky map up to a single free calibration parameter---i.e., we find no evidence for systematic errors in either data set. As a by-product, we improve the precision of the SPT calibration by nearly an order of magnitude, from 2.6% to 0.3% in power. Finally, we compare all three cross-spectra to the full-sky Planck power spectrum and find marginal evidence for differences between the power spectra from the SPT-SZ footprint and the full sky. We model these differences as a power law in spherical harmonic multipole number. The best-fit value of this tilt is consistent among the three cross-spectra in the SPT-SZ footprint, implying that the source of this tilt is a sample variance fluctuation in the SPT-SZ region relative to the full sky. The consistency of cosmological parameters derived from these data sets is discussed in a companion paper.
