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Atacama Cosmology Telescope: Constraints on prerecombination early dark energy

Hill, J. Colin and Calabrese, Erminia and Aiola, Simone and Battaglia, Nicholas and Bolliet, Boris and Choi, Steve K. and Devlin, Mark J. and Duivenvoorden, Adriaan J. and Dunkley, Jo and Ferraro, Simone and Gallardo, Patricio A. and Gluscevic, Vera and Hasselfield, Matthew and Hilton, Matt and Hincks, Adam D. and Hlozek, Renee and Koopman, Brian J. and Kosowsky, Arthur and La Posta, Adrien and Louis, Thibaut and Madhavacheril, Mathew S. and McMahon, Jeff and Moodley, Kavilan and Naess, Sigurd and Natale, Umberto and Nati, Federico and Newburgh, Laura and Niemack, Michael D. and Page, Lyman A. and Partridge, Bruce and Qu, Frank J. and Salatino, Maria and Schillaci, Alessandro and Sehgal, Neelima and Sherwin, Blake D. and Sifón, Cristóbal and Spergel, David N. and Staggs, Suzanne T. and Storer, Emilie R. and van Engelen, Alexander and Vavagiakis, Eve M. and Wollack, Edward J. and Xu, Zhilei (2022) Atacama Cosmology Telescope: Constraints on prerecombination early dark energy. Physical Review D, 105 (12). Art. No. 123536. ISSN 2470-0010. doi:10.1103/physrevd.105.123536.

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The early dark energy (EDE) scenario aims to increase the value of the Hubble constant (H₀) inferred from cosmic microwave background (CMB) data over that found in the standard cosmological model (Λ CDM), via the introduction of a new form of energy density in the early Universe. The EDE component briefly accelerates cosmic expansion just prior to recombination, which reduces the physical size of the sound horizon imprinted in the CMB. Previous work has found that nonzero EDE is not preferred by Planck CMB power spectrum data alone, which yield a 95% confidence level (C.L.) upper limit f_(EDE) < 0.087 on the maximal fractional contribution of the EDE field to the cosmic energy budget. In this paper, we fit the EDE model to CMB data from the Atacama Cosmology Telescope (ACT) data release 4. We find that a combination of ACT, large-scale Planck TT (similar to WMAP), Planck CMB lensing, and BAO data prefers the existence of EDE at > 99.7% C.L.: f_(EDE) = 0.091^(+0.020)_(−0.036), with H₀ = 70.9^(+1.0)_(−2.0) km/s/Mpc (both 68% C.L.). From a model-selection standpoint, we find that EDE is favored over Λ CDM by these data at roughly 3σ significance. In contrast, a joint analysis of the full Planck and ACT data yields no evidence for EDE, as previously found for Planck alone. We show that the preference for EDE in ACT alone is driven by its TE and EE power spectrum data. The tight constraint on EDE from Planck alone is driven by its high-ℓ TT power spectrum data. Understanding whether these differing constraints are physical in nature, due to systematics, or simply a rare statistical fluctuation is of high priority. The best-fit EDE models to ACT and Planck exhibit coherent differences across a wide range of multipoles in TE and EE, indicating that a powerful test of this scenario is anticipated with near-future data from ACT and other ground-based experiments.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hill, J. Colin0000-0002-9539-0835
Calabrese, Erminia0000-0003-0837-0068
Aiola, Simone0000-0002-1035-1854
Battaglia, Nicholas0000-0001-5846-0411
Choi, Steve K.0000-0002-9113-7058
Devlin, Mark J.0000-0002-3169-9761
Duivenvoorden, Adriaan J.0000-0003-2856-2382
Dunkley, Jo0000-0002-7450-2586
Ferraro, Simone0000-0003-4992-7854
Gallardo, Patricio A.0000-0001-9731-3617
Hasselfield, Matthew0000-0002-2408-9201
Hilton, Matt0000-0002-8490-8117
Hincks, Adam D.0000-0003-1690-6678
Hlozek, Renee0000-0002-0965-7864
Koopman, Brian J.0000-0003-0744-2808
Kosowsky, Arthur0000-0002-3734-331X
Louis, Thibaut0000-0002-6849-4217
Madhavacheril, Mathew S.0000-0001-6740-5350
McMahon, Jeff0000-0002-7245-4541
Moodley, Kavilan0000-0001-6606-7142
Naess, Sigurd0000-0002-4478-7111
Nati, Federico0000-0002-8307-5088
Niemack, Michael D.0000-0001-7125-3580
Page, Lyman A.0000-0002-9828-3525
Partridge, Bruce0000-0001-6541-9265
Salatino, Maria0000-0003-4006-1134
Schillaci, Alessandro0000-0002-0512-1042
Sehgal, Neelima0000-0002-9674-4527
Sifón, Cristóbal0000-0002-8149-1352
Spergel, David N.0000-0002-5151-0006
Staggs, Suzanne T.0000-0002-7020-7301
Storer, Emilie R.0000-0003-1592-9659
Vavagiakis, Eve M.0000-0002-2105-7589
Wollack, Edward J.0000-0002-7567-4451
Xu, Zhilei0000-0001-5112-2567
Alternate Title:The Atacama Cosmology Telescope: Constraints on Pre-Recombination Early Dark Energy
Additional Information:© 2022 American Physical Society. (Received 14 September 2021; accepted 14 June 2022; published 30 June 2022) We are grateful to Evan McDonough and Michael Toomey for their contributions to the development of class_ede and for useful conversations, and we thank the Scientific Computing Core staff at the Flatiron Institute for computational support. The Flatiron Institute is supported by the Simons Foundation. E. C. acknowledges support from the STFC Ernest Rutherford Fellowship No. ST/M004856/2 and STFC Consolidated Grant No. ST/S00033X/1. EC and U. N. acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 849169). J. D. and E. S. acknowledge support from NSF Grant No. AST-1814971. N. S. acknowledges support from NSF Grant No. AST-1907657. M. Hi. and K. M. acknowledge support from the National Research Foundation of South Africa. V. G. is supported by the National Science Foundation under Grant No. PHY-2013951. Z. X. is supported by the Gordon and Betty Moore Foundation. Research at Perimeter Institute is supported in part by the Government of Canada through the Department of Innovation, Science, and Industry Canada and by the Province of Ontario through the Ministry of Colleges and Universities. A. D. H. acknowledges support from the Sutton Family Chair in Science, Christianity, and Cultures and from the Faculty of Arts and Science, University of Toronto. S. K. C. acknowledges support from NSF Grant No. AST-2001866. E. V. acknowledges support from the NSF GRFP via Grant No. DGE-1650441. C. S. acknowledges support from the Agencia Nacional de Investigación y Desarrollo (ANID) under FONDECYT Grant No. 11191125. This work was completed at the Aspen Center for Physics, which is supported by National Science Foundation Grant No. PHY-1607611. Support for ACT was through the U.S. National Science Foundation through Grants No. AST-0408698, No. AST-0965625, and No. AST-1440226 for the Atacama Cosmology Telescope (ACT) project, as well as Grants No. PHY-0355328, No. PHY-0855887, and No. 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 Agencia Nacional de Investigación y Desarrollo (ANID). The development of multichroic detectors and lenses was supported by NASA Grants No. NNX13AE56G and No. NNX14AB58G. Detector research at NIST was supported by the NIST Innovations in Measurement Science program. We acknowledge use of the matplotlib [97], numpy [98], getdist [82], cobaya [74], and cosmomc [75] packages and use of the Boltzmann codes camb [85] and class [84].
Funding AgencyGrant Number
Simons FoundationUNSPECIFIED
Science and Technology Facilities Council (STFC)ST/M004856/2
Science and Technology Facilities Council (STFC)ST/S00033X/1
European Research Council (ERC)849169
National Research Foundation (South Africa)UNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
Department of Innovation, Science, and Industry CanadaUNSPECIFIED
Ontario Ministry of Colleges and UniversitiesUNSPECIFIED
Sutton Family Chair in Science, Christianity, and CulturesUNSPECIFIED
University of TorontoUNSPECIFIED
NSF Graduate Research FellowshipDGE-1650441
Agencia Nacional de Investigación y Desarrollo (ANID)UNSPECIFIED
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)11191125
Princeton UniversityUNSPECIFIED
Canada Foundation for InnovationUNSPECIFIED
University of PennsylvaniaUNSPECIFIED
National Institute of Standards and Technology (NIST)UNSPECIFIED
Issue or Number:12
Record Number:CaltechAUTHORS:20220715-332590000
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:115634
Deposited By: George Porter
Deposited On:18 Jul 2022 15:08
Last Modified:26 Jul 2022 22:41

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