Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters
Planck Collaboration. The six parameters of the standard ΛCDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angul...
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Digital.CSIC (Spanish National Research Council) |
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English |
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Cosmology: theory Cosmic background radiation Cosmological parameters Cosmology: observations |
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Cosmology: theory Cosmic background radiation Cosmological parameters Cosmology: observations Aghanim, N. Akrami, Y. Ashdown, M. Aumont, J. Baccigalupi, C. Ballardini, M. Banday, A. J. Barreiro, R. Belén Bartolo, Nicola Basak, S. Benabed, K. Kim, J. Kisner, T. S. Mennella, A. Knox, L. Krachmalnicof, N. Kunz, M. Kurki-Suonio, H. Lagache, Guilaine Lamarre, J.-M. Lasenby, A. Renzi, A. Lattanzi, M. Lawrence, C. R. Jeune, M. le Migliaccio, M. Levrier, F. Lewis, A. Liguori, Michele Lilje, P. B. Lilley, M. Lindholm, V. Rocha, G. López-Caniego, M. Lubin, P. M. Ma, Y.-Z Macías-Pérez, J. F. Millea, M. Maggio, G. Maino, D. Mandolesi, N. Mangilli, A. Maris, M. Bonaldi, A. Martin, P. G. Martínez-González, Enrique Matarrese, S. Mauri, N. Miville-Deschênes, M. A. Molinari, D. Moneti, A. Montier, L. Morgante, G. Bersanelli, M. Rossetti, M. Moss, A. Narimani, A. Natoli, P. Oxborrow, C. A. Pagano, L. Paoletti, D. Partridge, B. Patanchon, G. Patrizii, L. Pettorino, V. Roudier, G. Bielewicz, P. Piacentini, F. Polastri, L. Polenta, G. Puget, J.-L. Rachen, J. P. Racine, B. Reinecke, M. Remazeilles, M. Rubiño-Martín, J. A. Ruiz-Granados, Beatriz Salvati, L. Sandri, M. Savelainen, M. Efstathiou, G. Scott, D. Sirignano, C. Sirri, G. Bonavera, Laura Stanco, L. Suur-Uski, A.-S. Tauber, J. A. Tavagnacco, D. Tenti, M. Toffolatti, L. Elsner, F. Tomasi, M. Tristram, M. Trombetti, T. Valiviita, J. Bond, J. R. Tent, F. van Vielva, P. Villa, F. Vittorio, N. Wandelt, B. D. Enßlin, T. A. Wehus, I. K. White, Martin Zacchei, A. Zonca, A. Borrill, J. Bouchet, F. R. Boulanger, F. Bracco, Andrea Burigana, C. Calabrese, E. Eriksen, H. K. Cardoso, J. F. Challinor, A. Chiang, H. C. Colombo, L.P.L. Combet, C. Crill, B. P. Curto, Andrés Cuttaia, F. Bernardis, P. de Rosa, A. de Fantaye, Y. Zotti, G. de Delabrouille, J. Valentino, E. di Dickinson, C. Diego, José María Doré, O. Ducout, A. Dupac, X. Dusini, S. Finelli, F. Forastieri, F. Frailis, M. Franceschi, E. Frolov, A. McEwen, J. D. Galeotta, S. Galli, S. Ganga, K. Génova-Santos, R. Gerbino, M. González-Nuevo, J. Górski, K. M. Gratton, S. Gruppuso, A. Gudmundsson, J. E. Meinhold, P. R. Herranz, D. Hivon, E. Huang, Z. Jaffe, A. H. Jones, W. C. Keihänen, E. Keskitalo, R. Kiiveri, K. Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
topic_facet |
Cosmology: theory Cosmic background radiation Cosmological parameters Cosmology: observations |
description |
Planck Collaboration. The six parameters of the standard ΛCDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium τ, the baryon density ωb, the matter density ωm, the angular size of the sound horizon θ∗, the spectral index of the primordial power spectrum, ns, and Ase− 2τ (where As is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment ℓ < 800 in the Planck temperature power spectrum) and an all angular-scale data set (ℓ < 2500Planck temperature power spectrum), each with a prior on τ of 0.07 ± 0.02. We find that the shifts, in units of the 1σ expected dispersion for each parameter, are { Δτ,ΔAse− 2τ,Δns,Δωm,Δωb,Δθ∗ } = { −1.7,−2.2,1.2,−2.0,1.1,0.9 }, with a χ2 value of 8.0. We find that this χ2 value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2σ in 9% of simulated data sets, meaning that the shifts are not unusually large. Comparing ℓ < 800 instead to ℓ> 800, or splitting at a different multipole, yields similar results. We examined the ℓ < 800 model residuals in the ℓ> 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in ΛCDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is τ, which, at fixed Ase− 2τ, affects the ℓ> 800 temperature power spectrum solely through the associated change in As and the impact of that on the lensing potential power spectrum. We also ask, “what is it about the power spectrum at ℓ < 800 that leads to somewhat different best-fit parameters than come from the full ℓ range?” We find that if we discard the data at ℓ < 30, where there is a roughly 2σ downward fluctuation in power relative to the model that best fits the full ℓ range, the ℓ < 800 best-fit parameters shift significantly towards the ℓ < 2500 best-fit parameters. In contrast, including ℓ < 30, this previously noted “low-ℓ deficit” drives ns up and impacts parameters correlated with ns, such as ωm and H0. As expected, the ℓ < 30 data have a much greater impact on the ℓ < 800 best fit than on the ℓ < 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-ℓ residuals and the deficit in low-ℓ power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between PlanckTT data and two other CMB data sets, namely the Planck lensing reconstruction and the TT power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the ΛCDM model. The Planck Collaboration acknowledges the support of: ESA; CNES, and CNRS/INSU-IN2P3-INP (France); ASI, CNR, and INAF (Italy); NASA and DoE (USA); STFC and UKSA (UK); CSIC, MINECO, JA, and RES (Spain); Tekes, AoF, and CSC (Finland); DLR and MPG (Germany); CSA (Canada); DTU Space (Denmark); SER/SSO (Switzerland); RCN (Norway); SFI (Ireland); FCT/MCTES (Portugal); ERC and PRACE (EU). This work was also supported by the Labex ILP (reference ANR-10-LABX-63). Peer Reviewed |
author2 |
Fundação para a Ciência e a Tecnologia (Portugal) European Research Council European Commission Ministerio de Economía, Industria y Competitividad (España) Consejo Superior de Investigaciones Científicas (España) Department of Energy (US) National Aeronautics and Space Administration (US) Consiglio Nazionale delle Ricerche Istituto Nazionale di Astrofisica Agenzia Spaziale Italiana Centre National D'Etudes Spatiales (France) Centre National de la Recherche Scientifique (France) European Space Agency Science and Technology Facilities Council (UK) Ministério da Ciência, Tecnologia e Ensino Superior (Portugal) Science Foundation Ireland Swiss Space Office DTU Space (Denmark) Canadian Space Agency Federal Ministry of Education and Research (Germany) German Research Foundation Academy of Finland Center for Science (Finland) Red Española de Supercomputación Research Council of Norway |
format |
Article in Journal/Newspaper |
author |
Aghanim, N. Akrami, Y. Ashdown, M. Aumont, J. Baccigalupi, C. Ballardini, M. Banday, A. J. Barreiro, R. Belén Bartolo, Nicola Basak, S. Benabed, K. Kim, J. Kisner, T. S. Mennella, A. Knox, L. Krachmalnicof, N. Kunz, M. Kurki-Suonio, H. Lagache, Guilaine Lamarre, J.-M. Lasenby, A. Renzi, A. Lattanzi, M. Lawrence, C. R. Jeune, M. le Migliaccio, M. Levrier, F. Lewis, A. Liguori, Michele Lilje, P. B. Lilley, M. Lindholm, V. Rocha, G. López-Caniego, M. Lubin, P. M. Ma, Y.-Z Macías-Pérez, J. F. Millea, M. Maggio, G. Maino, D. Mandolesi, N. Mangilli, A. Maris, M. Bonaldi, A. Martin, P. G. Martínez-González, Enrique Matarrese, S. Mauri, N. Miville-Deschênes, M. A. Molinari, D. Moneti, A. Montier, L. Morgante, G. Bersanelli, M. Rossetti, M. Moss, A. Narimani, A. Natoli, P. Oxborrow, C. A. Pagano, L. Paoletti, D. Partridge, B. Patanchon, G. Patrizii, L. Pettorino, V. Roudier, G. Bielewicz, P. Piacentini, F. Polastri, L. Polenta, G. Puget, J.-L. Rachen, J. P. Racine, B. Reinecke, M. Remazeilles, M. Rubiño-Martín, J. A. Ruiz-Granados, Beatriz Salvati, L. Sandri, M. Savelainen, M. Efstathiou, G. Scott, D. Sirignano, C. Sirri, G. Bonavera, Laura Stanco, L. Suur-Uski, A.-S. Tauber, J. A. Tavagnacco, D. Tenti, M. Toffolatti, L. Elsner, F. Tomasi, M. Tristram, M. Trombetti, T. Valiviita, J. Bond, J. R. Tent, F. van Vielva, P. Villa, F. Vittorio, N. Wandelt, B. D. Enßlin, T. A. Wehus, I. K. White, Martin Zacchei, A. Zonca, A. Borrill, J. Bouchet, F. R. Boulanger, F. Bracco, Andrea Burigana, C. Calabrese, E. Eriksen, H. K. Cardoso, J. F. Challinor, A. Chiang, H. C. Colombo, L.P.L. Combet, C. Crill, B. P. Curto, Andrés Cuttaia, F. Bernardis, P. de Rosa, A. de Fantaye, Y. Zotti, G. de Delabrouille, J. Valentino, E. di Dickinson, C. Diego, José María Doré, O. Ducout, A. Dupac, X. Dusini, S. Finelli, F. Forastieri, F. Frailis, M. Franceschi, E. Frolov, A. McEwen, J. D. Galeotta, S. Galli, S. Ganga, K. Génova-Santos, R. Gerbino, M. González-Nuevo, J. Górski, K. M. Gratton, S. Gruppuso, A. Gudmundsson, J. E. Meinhold, P. R. Herranz, D. Hivon, E. Huang, Z. Jaffe, A. H. Jones, W. C. Keihänen, E. Keskitalo, R. Kiiveri, K. |
author_facet |
Aghanim, N. Akrami, Y. Ashdown, M. Aumont, J. Baccigalupi, C. Ballardini, M. Banday, A. J. Barreiro, R. Belén Bartolo, Nicola Basak, S. Benabed, K. Kim, J. Kisner, T. S. Mennella, A. Knox, L. Krachmalnicof, N. Kunz, M. Kurki-Suonio, H. Lagache, Guilaine Lamarre, J.-M. Lasenby, A. Renzi, A. Lattanzi, M. Lawrence, C. R. Jeune, M. le Migliaccio, M. Levrier, F. Lewis, A. Liguori, Michele Lilje, P. B. Lilley, M. Lindholm, V. Rocha, G. López-Caniego, M. Lubin, P. M. Ma, Y.-Z Macías-Pérez, J. F. Millea, M. Maggio, G. Maino, D. Mandolesi, N. Mangilli, A. Maris, M. Bonaldi, A. Martin, P. G. Martínez-González, Enrique Matarrese, S. Mauri, N. Miville-Deschênes, M. A. Molinari, D. Moneti, A. Montier, L. Morgante, G. Bersanelli, M. Rossetti, M. Moss, A. Narimani, A. Natoli, P. Oxborrow, C. A. Pagano, L. Paoletti, D. Partridge, B. Patanchon, G. Patrizii, L. Pettorino, V. Roudier, G. Bielewicz, P. Piacentini, F. Polastri, L. Polenta, G. Puget, J.-L. Rachen, J. P. Racine, B. Reinecke, M. Remazeilles, M. Rubiño-Martín, J. A. Ruiz-Granados, Beatriz Salvati, L. Sandri, M. Savelainen, M. Efstathiou, G. Scott, D. Sirignano, C. Sirri, G. Bonavera, Laura Stanco, L. Suur-Uski, A.-S. Tauber, J. A. Tavagnacco, D. Tenti, M. Toffolatti, L. Elsner, F. Tomasi, M. Tristram, M. Trombetti, T. Valiviita, J. Bond, J. R. Tent, F. van Vielva, P. Villa, F. Vittorio, N. Wandelt, B. D. Enßlin, T. A. Wehus, I. K. White, Martin Zacchei, A. Zonca, A. Borrill, J. Bouchet, F. R. Boulanger, F. Bracco, Andrea Burigana, C. Calabrese, E. Eriksen, H. K. Cardoso, J. F. Challinor, A. Chiang, H. C. Colombo, L.P.L. Combet, C. Crill, B. P. Curto, Andrés Cuttaia, F. Bernardis, P. de Rosa, A. de Fantaye, Y. Zotti, G. de Delabrouille, J. Valentino, E. di Dickinson, C. Diego, José María Doré, O. Ducout, A. Dupac, X. Dusini, S. Finelli, F. Forastieri, F. Frailis, M. Franceschi, E. Frolov, A. McEwen, J. D. Galeotta, S. Galli, S. Ganga, K. Génova-Santos, R. Gerbino, M. González-Nuevo, J. Górski, K. M. Gratton, S. Gruppuso, A. Gudmundsson, J. E. Meinhold, P. R. Herranz, D. Hivon, E. Huang, Z. Jaffe, A. H. Jones, W. C. Keihänen, E. Keskitalo, R. Kiiveri, K. |
author_sort |
Aghanim, N. |
title |
Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
title_short |
Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
title_full |
Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
title_fullStr |
Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
title_full_unstemmed |
Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
title_sort |
planck intermediate results li. features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters |
publisher |
EDP Sciences |
publishDate |
2017 |
url |
http://hdl.handle.net/10261/170624 https://doi.org/10.1051/0004-6361/201629504 https://doi.org/10.13039/501100003339 https://doi.org/10.13039/100000104 https://doi.org/10.13039/501100004462 https://doi.org/10.13039/501100005184 https://doi.org/10.13039/501100003981 https://doi.org/10.13039/501100002830 https://doi.org/10.13039/501100004794 https://doi.org/10.13039/501100000844 https://doi.org/10.13039/501100000271 https://doi.org/10.13039/501100006111 https://doi.org/10.13039/501100001602 https://doi.org/10.13039/501100000016 https://doi.org/10.13039/501100002347 https://doi.org/10.13039/501100001659 https://doi.org/10.13039/501100000780 https://doi.org/10.13039/501100001871 https://doi.org/10.13039/501100000781 |
geographic |
Canada Norway South Pole |
geographic_facet |
Canada Norway South Pole |
genre |
South pole |
genre_facet |
South pole |
op_relation |
Publisher's version https://doi.org/10.1051/0004-6361/201629504 Sí doi:10.1051/0004-6361/201629504 issn: 0004-6361 e-issn: 1432-0746 Astronomy and Astrophysics 607: A95 (2017) http://hdl.handle.net/10261/170624 http://dx.doi.org/10.13039/501100003339 http://dx.doi.org/10.13039/100000104 http://dx.doi.org/10.13039/501100004462 http://dx.doi.org/10.13039/501100005184 http://dx.doi.org/10.13039/501100003981 http://dx.doi.org/10.13039/501100002830 http://dx.doi.org/10.13039/501100004794 http://dx.doi.org/10.13039/501100000844 http://dx.doi.org/10.13039/501100000271 http://dx.doi.org/10.13039/501100006111 http://dx.doi.org/10.13039/501100001602 http://dx.doi.org/10.13039/501100000016 http://dx.doi.org/10.13039/501100002347 http://dx.doi.org/10.13039/501100001659 http://dx.doi.org/10.13039/501100000780 http://dx.doi.org/10.13039/501100001871 http://dx.doi.org/10.13039/501100000781 |
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openAccess |
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https://doi.org/10.1051/0004-6361/201629504 https://doi.org/10.13039/501100003339 https://doi.org/10.13039/100000104 https://doi.org/10.13039/501100004462 https://doi.org/10.13039/501100005184 https://doi.org/10.13039/501100003981 https://doi. |
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Astronomy & Astrophysics |
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607 |
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A95 |
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ftcsic:oai:digital.csic.es:10261/170624 2023-05-15T18:23:26+02:00 Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters Aghanim, N. Akrami, Y. Ashdown, M. Aumont, J. Baccigalupi, C. Ballardini, M. Banday, A. J. Barreiro, R. Belén Bartolo, Nicola Basak, S. Benabed, K. Kim, J. Kisner, T. S. Mennella, A. Knox, L. Krachmalnicof, N. Kunz, M. Kurki-Suonio, H. Lagache, Guilaine Lamarre, J.-M. Lasenby, A. Renzi, A. Lattanzi, M. Lawrence, C. R. Jeune, M. le Migliaccio, M. Levrier, F. Lewis, A. Liguori, Michele Lilje, P. B. Lilley, M. Lindholm, V. Rocha, G. López-Caniego, M. Lubin, P. M. Ma, Y.-Z Macías-Pérez, J. F. Millea, M. Maggio, G. Maino, D. Mandolesi, N. Mangilli, A. Maris, M. Bonaldi, A. Martin, P. G. Martínez-González, Enrique Matarrese, S. Mauri, N. Miville-Deschênes, M. A. Molinari, D. Moneti, A. Montier, L. Morgante, G. Bersanelli, M. Rossetti, M. Moss, A. Narimani, A. Natoli, P. Oxborrow, C. A. Pagano, L. Paoletti, D. Partridge, B. Patanchon, G. Patrizii, L. Pettorino, V. Roudier, G. Bielewicz, P. Piacentini, F. Polastri, L. Polenta, G. Puget, J.-L. Rachen, J. P. Racine, B. Reinecke, M. Remazeilles, M. Rubiño-Martín, J. A. Ruiz-Granados, Beatriz Salvati, L. Sandri, M. Savelainen, M. Efstathiou, G. Scott, D. Sirignano, C. Sirri, G. Bonavera, Laura Stanco, L. Suur-Uski, A.-S. Tauber, J. A. Tavagnacco, D. Tenti, M. Toffolatti, L. Elsner, F. Tomasi, M. Tristram, M. Trombetti, T. Valiviita, J. Bond, J. R. Tent, F. van Vielva, P. Villa, F. Vittorio, N. Wandelt, B. D. Enßlin, T. A. Wehus, I. K. White, Martin Zacchei, A. Zonca, A. Borrill, J. Bouchet, F. R. Boulanger, F. Bracco, Andrea Burigana, C. Calabrese, E. Eriksen, H. K. Cardoso, J. F. Challinor, A. Chiang, H. C. Colombo, L.P.L. Combet, C. Crill, B. P. Curto, Andrés Cuttaia, F. Bernardis, P. de Rosa, A. de Fantaye, Y. Zotti, G. de Delabrouille, J. Valentino, E. di Dickinson, C. Diego, José María Doré, O. Ducout, A. Dupac, X. Dusini, S. Finelli, F. Forastieri, F. Frailis, M. Franceschi, E. Frolov, A. McEwen, J. D. Galeotta, S. Galli, S. Ganga, K. Génova-Santos, R. Gerbino, M. González-Nuevo, J. Górski, K. M. Gratton, S. Gruppuso, A. Gudmundsson, J. E. Meinhold, P. R. Herranz, D. Hivon, E. Huang, Z. Jaffe, A. H. Jones, W. C. Keihänen, E. Keskitalo, R. Kiiveri, K. Fundação para a Ciência e a Tecnologia (Portugal) European Research Council European Commission Ministerio de Economía, Industria y Competitividad (España) Consejo Superior de Investigaciones Científicas (España) Department of Energy (US) National Aeronautics and Space Administration (US) Consiglio Nazionale delle Ricerche Istituto Nazionale di Astrofisica Agenzia Spaziale Italiana Centre National D'Etudes Spatiales (France) Centre National de la Recherche Scientifique (France) European Space Agency Science and Technology Facilities Council (UK) Ministério da Ciência, Tecnologia e Ensino Superior (Portugal) Science Foundation Ireland Swiss Space Office DTU Space (Denmark) Canadian Space Agency Federal Ministry of Education and Research (Germany) German Research Foundation Academy of Finland Center for Science (Finland) Red Española de Supercomputación Research Council of Norway 2017 http://hdl.handle.net/10261/170624 https://doi.org/10.1051/0004-6361/201629504 https://doi.org/10.13039/501100003339 https://doi.org/10.13039/100000104 https://doi.org/10.13039/501100004462 https://doi.org/10.13039/501100005184 https://doi.org/10.13039/501100003981 https://doi.org/10.13039/501100002830 https://doi.org/10.13039/501100004794 https://doi.org/10.13039/501100000844 https://doi.org/10.13039/501100000271 https://doi.org/10.13039/501100006111 https://doi.org/10.13039/501100001602 https://doi.org/10.13039/501100000016 https://doi.org/10.13039/501100002347 https://doi.org/10.13039/501100001659 https://doi.org/10.13039/501100000780 https://doi.org/10.13039/501100001871 https://doi.org/10.13039/501100000781 eng eng EDP Sciences Publisher's version https://doi.org/10.1051/0004-6361/201629504 Sí doi:10.1051/0004-6361/201629504 issn: 0004-6361 e-issn: 1432-0746 Astronomy and Astrophysics 607: A95 (2017) http://hdl.handle.net/10261/170624 http://dx.doi.org/10.13039/501100003339 http://dx.doi.org/10.13039/100000104 http://dx.doi.org/10.13039/501100004462 http://dx.doi.org/10.13039/501100005184 http://dx.doi.org/10.13039/501100003981 http://dx.doi.org/10.13039/501100002830 http://dx.doi.org/10.13039/501100004794 http://dx.doi.org/10.13039/501100000844 http://dx.doi.org/10.13039/501100000271 http://dx.doi.org/10.13039/501100006111 http://dx.doi.org/10.13039/501100001602 http://dx.doi.org/10.13039/501100000016 http://dx.doi.org/10.13039/501100002347 http://dx.doi.org/10.13039/501100001659 http://dx.doi.org/10.13039/501100000780 http://dx.doi.org/10.13039/501100001871 http://dx.doi.org/10.13039/501100000781 openAccess Cosmology: theory Cosmic background radiation Cosmological parameters Cosmology: observations artículo 2017 ftcsic https://doi.org/10.1051/0004-6361/201629504 https://doi.org/10.13039/501100003339 https://doi.org/10.13039/100000104 https://doi.org/10.13039/501100004462 https://doi.org/10.13039/501100005184 https://doi.org/10.13039/501100003981 https://doi. 2019-08-27T23:23:47Z Planck Collaboration. The six parameters of the standard ΛCDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium τ, the baryon density ωb, the matter density ωm, the angular size of the sound horizon θ∗, the spectral index of the primordial power spectrum, ns, and Ase− 2τ (where As is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment ℓ < 800 in the Planck temperature power spectrum) and an all angular-scale data set (ℓ < 2500Planck temperature power spectrum), each with a prior on τ of 0.07 ± 0.02. We find that the shifts, in units of the 1σ expected dispersion for each parameter, are { Δτ,ΔAse− 2τ,Δns,Δωm,Δωb,Δθ∗ } = { −1.7,−2.2,1.2,−2.0,1.1,0.9 }, with a χ2 value of 8.0. We find that this χ2 value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2σ in 9% of simulated data sets, meaning that the shifts are not unusually large. Comparing ℓ < 800 instead to ℓ> 800, or splitting at a different multipole, yields similar results. We examined the ℓ < 800 model residuals in the ℓ> 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in ΛCDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is τ, which, at fixed Ase− 2τ, affects the ℓ> 800 temperature power spectrum solely through the associated change in As and the impact of that on the lensing potential power spectrum. We also ask, “what is it about the power spectrum at ℓ < 800 that leads to somewhat different best-fit parameters than come from the full ℓ range?” We find that if we discard the data at ℓ < 30, where there is a roughly 2σ downward fluctuation in power relative to the model that best fits the full ℓ range, the ℓ < 800 best-fit parameters shift significantly towards the ℓ < 2500 best-fit parameters. In contrast, including ℓ < 30, this previously noted “low-ℓ deficit” drives ns up and impacts parameters correlated with ns, such as ωm and H0. As expected, the ℓ < 30 data have a much greater impact on the ℓ < 800 best fit than on the ℓ < 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-ℓ residuals and the deficit in low-ℓ power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between PlanckTT data and two other CMB data sets, namely the Planck lensing reconstruction and the TT power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the ΛCDM model. The Planck Collaboration acknowledges the support of: ESA; CNES, and CNRS/INSU-IN2P3-INP (France); ASI, CNR, and INAF (Italy); NASA and DoE (USA); STFC and UKSA (UK); CSIC, MINECO, JA, and RES (Spain); Tekes, AoF, and CSC (Finland); DLR and MPG (Germany); CSA (Canada); DTU Space (Denmark); SER/SSO (Switzerland); RCN (Norway); SFI (Ireland); FCT/MCTES (Portugal); ERC and PRACE (EU). This work was also supported by the Labex ILP (reference ANR-10-LABX-63). Peer Reviewed Article in Journal/Newspaper South pole Digital.CSIC (Spanish National Research Council) Canada Norway South Pole Astronomy & Astrophysics 607 A95 |