A measurement of the cosmic microwave background gravitational lensing potential from 100 square degrees of SPTpol data

• Published in: The Astrophysical Journal
• Main Authors: Story, K. T., Hanson, D., Ade, P. A. R., Aird, K. A., Austermann, J. E., Beall, J. A., Bender, A. N., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Chiang, H. C., Cho, H. -M., Citron, R., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W., Gallicchio, J., Gao, J., George, E. M., Gilbert, A., Halverson, N. W., Harrington, N., Henning, J. W., Hilton, G. C., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., Hrubes, J. D., Huang, N., Hubmayr, J., Irwin, K. D., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Li, D., Liang, C., Luong-Van, D., McMahon, J. J., Mehl, J., Meyer, S. S., Mocanu, L., Montroy, T. E., Natoli, T., Nibarger, J. P., Novosad, V., Padin, S., Pryke, C., Reichardt, C. L., Ruhl, J. E., Saliwanchik, B. R., Sayre, J. T., Schaffer, K. K., Smecher, G., Stark, A. A., Tucker, C., Vanderlinde, K., Vieira, J. D., Wang, G., Whitehorn, N., Yefremenko, V., Zahn, O.
• Language: unknown
• Published: 2022
• Subjects: 79 ASTRONOMY AND ASTROPHYSICS; South Pole; South pole
• Online Access: http://www.osti.gov/servlets/purl/1326855; https://www.osti.gov/biblio/1326855; https://doi.org/10.1088/0004-637X/810/1/50

Here, we present a measurement of the cosmic microwave background (CMB) gravitational lensing potential using data from the first two seasons of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope. The observations used in this work cover 100 deg 2 of sky with arcminute resolution at 150 GHz. Using a quadratic estimator, we make maps of the CMB lensing potential from combinations of CMB temperature and polarization maps. We combine these lensing potential maps to form a minimum-variance (MV) map. The lensing potential is measured with a signal-to-noise ratio of greater than one for angular multipoles between $100\lt L\lt 250$. This is the highest signal-to-noise mass map made from the CMB to date and will be powerful in cross-correlation with other tracers of large-scale structure. We calculate the power spectrum of the lensing potential for each estimator, and we report the value of the MV power spectrum between $100\lt L\lt 2000$ as our primary result. We constrain the ratio of the spectrum to a fiducial ΛCDM model to be AMV = 0.92 ± 0.14 (Stat.) ± 0.08 (Sys.). Restricting ourselves to polarized data only, we find A POL = 0.92 ± 0.24 (Stat.) ± 0.11 (Sys.). This measurement rejects the hypothesis of no lensing at $5.9\sigma $ using polarization data alone, and at $14\sigma $ using both temperature and polarization data.