CaltechAUTHORS
Published December 2020 | Version Accepted Version
Journal Article Open

Atacama Cosmology Telescope: a measurement of the Cosmic Microwave Background power spectra at 98 and 150 GHz

Creators

  • 1. ROR icon Cornell University
  • 2. ROR icon Princeton University
  • 3. ROR icon Pennsylvania State University
  • 4. ROR icon Yale University
  • 5. ROR icon University of Pennsylvania
  • 6. ROR icon University of Oxford
  • 7. ROR icon Johns Hopkins University
  • 8. ROR icon Cardiff University
  • 9. ROR icon University of British Columbia
  • 10. ROR icon National Institute of Standards and Technology
  • 11. ROR icon University of Michigan–Ann Arbor
  • 12. ROR icon Canadian Institute for Theoretical Astrophysics
  • 13. ROR icon University of Chile
  • 14. ROR icon University of Chicago
  • 15. ROR icon SLAC National Accelerator Laboratory
  • 16. ROR icon Institute for Advanced Study
  • 17. ROR icon University of KwaZulu-Natal
  • 18. ROR icon University of California, Berkeley
  • 19. ROR icon University of Cambridge
  • 20. ROR icon Pontificia Universidad Católica de Chile
  • 21. ROR icon Goddard Space Flight Center
  • 22. ROR icon Florida State University
  • 23. ROR icon University of Southern California
  • 24. ROR icon University of Arizona
  • 25. ROR icon University of Pittsburgh
  • 26. ROR icon Stony Brook University
  • 27. ROR icon Columbia University
  • 28. ROR icon University of Toronto
  • 29. ROR icon Rutgers, The State University of New Jersey
  • 30. ROR icon Stanford University
  • 31. ROR icon Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
  • 32. ROR icon Perimeter Institute
  • 33. ROR icon Institut d'Astrophysique Spatiale
  • 34. ROR icon University of Illinois Urbana-Champaign
  • 35. ROR icon University of Milano-Bicocca
  • 36. ROR icon Haverford College
  • 37. ROR icon Kavli Institute for Particle Astrophysics and Cosmology
  • 38. ROR icon California Institute of Technology
  • 39. ROR icon McGill University
  • 40. ROR icon Pontificial Catholic University of Valparaiso
  • 41. ROR icon West Chester University
  • 42. ROR icon Carnegie Mellon University
  • 43. ROR icon Arizona State University

Abstract

We present the temperature and polarization angular power spectra of the CMB measured by the Atacama Cosmology Telescope (ACT) from 5400 deg² of the 2013–2016 survey, which covers >15000 deg² at 98 and 150 GHz. For this analysis we adopt a blinding strategy to help avoid confirmation bias and, related to this, show numerous checks for systematic error done before unblinding. Using the likelihood for the cosmological analysis we constrain secondary sources of anisotropy and foreground emission, and derive a "CMB-only" spectrum that extends to ℓ=4000. At large angular scales, foreground emission at 150 GHz is ~1% of TT and EE within our selected regions and consistent with that found by Planck. Using the same likelihood, we obtain the cosmological parameters for ΛCDM for the ACT data alone with a prior on the optical depth of τ=0.065±0.015. ΛCDM is a good fit. The best-fit model has a reduced χ² of 1.07 (PTE=0.07) with H₀=67.9±1.5 km/s/Mpc. We show that the lensing BB signal is consistent with ΛCDM and limit the celestial EB polarization angle to ψP =−0.07o±0.09o. We directly cross correlate ACT with Planck and observe generally good agreement but with some discrepancies in TE. All data on which this analysis is based will be publicly released.

Additional Information

© 2020 IOP Publishing Ltd and Sissa Medialab. Received 16 July 2020; Accepted 19 November 2020; Published 30 December 2020. This work was supported by the U.S. National Science Foundation through awards AST-0408698, AST-0965625, and AST-1440226 for the ACT project, as well as awards PHY-0355328, PHY-0855887 and PHY-1214379. Funding was also provided by Princeton University, the University of Pennsylvania, and a Canada Foundation for Innovation (CFI) award to UBC. ACT operates in the Parque Astronómico Atacama in northern Chile under the auspices of the Comisión Nacional de Investigación (CONICYT). Computations were performed on the Niagara supercomputer at the SciNet HPC Consortium and on the Simons-Popeye cluster of the Flatiron Institute. SciNet is funded by the CFI under the auspices of Compute Canada, the Government of Ontario, the Ontario Research Fund-Research Excellence, and the University of Toronto. Cosmological analyses were performed on the Hawk high-performance computing cluster at the Advanced Research Computing at Cardiff (ARCCA). We would like to thank the Scientific Computing Core (SCC) team at the Flatiron Institute, especially Nick Carriero, for their support. Flatiron Institute is supported by the Simons Foundation. Additional computations were performed on Hippo at the University of KwaZulu-Natal, on Tiger as part of Princeton Research Computing resources at Princeton University, on Feynman at Princeton University, and on Cori at NERSC. The development of multichroic detectors and lenses was supported by NASA grants NNX13AE56G and NNX14AB58G. Detector research at NIST was supported by the NIST Innovations in Measurement Science program. We thank Bert Harrop for his extensive efforts on the assembly of the detector arrays. The shops at Penn and Princeton have time and again built beautiful instrumentation on which ACT depends. We also thank Toby Marriage for numerous contributions. SKC acknowledges support from the Cornell Presidential Postdoctoral Fellowship. RD thanks CONICYT for grant BASAL CATA AFB-170002. ZL, ES and JD are supported through NSF grant AST-1814971. KM and MHi acknowledge support from the National Research Foundation of South Africa. MDN acknowledges support from NSF award AST-1454881. DH, AM, and NS acknowledge support from NSF grant numbers AST-1513618 and AST-1907657. EC acknowledges support from the STFC Ernest Rutherford Fellowship ST/M004856/2 and STFC Consolidated Grant ST/S00033X/1, and from the Horizon 2020 ERC Starting Grant (Grant agreement No 849169). NB acknowledges support from NSF grant AST-1910021. ML was supported by a Dicke Fellowship. LP gratefully acknowledges support from the Mishrahi and Wilkinson funds. RH acknowledges support as an Azrieli Global Scholar in CIfAR's Gravity & the Extreme Universe Program and as an Alfred. P. Sloan Research Fellow. RH is also supported by Canada's NSERC Discovery Grants program and the Dunlap Institute, which was established with an endowment by the David Dunlap family and the University of Toronto. We thank our many colleagues from ALMA, APEX, CLASS, and Polarbear/Simons Array who have helped us at critical junctures. Colleagues at AstroNorte and RadioSky provide logistical support and keep operations in Chile running smoothly. Lastly, we gratefully acknowledge the many publicly available software packages that were essential for parts of this analysis. They include CosmoMC (Lewis 2013; Lewis & Bridle 2002), CAMB (Lewis et al. 2000), healpy (Zonca et al. 2019), HEALPix (Górski et al. 2005), the SLATEC29 Fortran subroutine DRC3JJ.F9, the SOFA library (IAU SOFA Board 2019), libsharp (Reinecke & Seljebotn 2013), and pixell30. This research made use of Astropy31, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013; Price-Whelan et al. 2018). We also acknowledge use of the matplotlib (Hunter 2007) package and the Python Image Library for producing plots in this paper.

Attached Files

Accepted Version - 2007.07289.pdf

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2007.07289.pdf

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Additional details

Identifiers

Eprint ID
108029
Resolver ID
CaltechAUTHORS:20210212-080400390

Related works

Describes
https://arxiv.org/abs/2007.07289 (URL)

Funding

NSF
AST-0408698
NSF
AST-0965625
NSF
AST-1440226
NSF
PHY-0355328
NSF
PHY-0855887
NSF
PHY-1214379
Princeton University
University of Pennsylvania
Canada Foundation for Innovation (CFI)
Comisión Nacional de Investigación Científica y Tecnológica (CONICYT)
Flatiron Institute
Compute Canada
Government of Ontario
Ontario Research Fund-Research Excellence
University of Toronto
Simons Foundation
NASA
NNX13AE56G
NASA
NNX14AB58G
National Institute of Standards and Technology (NIST)
Cornell University
BASAL-CATA
AFB-170002
NSF
AST-1814971
National Research Foundation (South Africa)
NSF
AST-1454881
NSF
AST-1513618
NSF
AST-1907657
Science and Technology Facilities Council (STFC)
ST/M004856/2
Science and Technology Facilities Council (STFC)
ST/S00033X/1
European Research Council (ERC)
849169
NSF
AST-1910021
Mishrahi Fund
Wilkinson Fund
Canadian Institute for Advanced Research (CIFAR)
Alfred P. Sloan Foundation
Natural Sciences and Engineering Research Council of Canada (NSERC)
Dunlap Institute
David Dunlap Family

Dates

Created
2021-02-12
Created from EPrint's datestamp field
Updated
2022-07-12
Created from EPrint's last_modified field