Skip to Main content Skip to Navigation
Journal articles

Planck 2018 results: XI. Polarized dust foregrounds

Y. Akrami 1 M. Ashdown J. Aumont C. Baccigalupi M. Ballardini A. J. Banday 2 R. B. Barreiro N. Bartolo S. Basak K. Benabed 3 J.-P. Bernard M. Bersanelli 4 P. Bielewicz J. R. Bond 5 J. Borrill 6 F. R. Bouchet 7 F. Boulanger 8, 9, * A. Bracco M. Bucher 10 C. Burigana E. Calabrese J.-F. Cardoso 11 J. Carron 12 H. C. Chiang C. Combet 13 B. P. Crill P. de Bernardis 14 G. de Zotti J. Delabrouille 10 J.-M. Delouis 3 E. Di Valentino C. Dickinson J. M. Diego A. Ducout X. Dupac G. Efstathiou F. Elsner 15 T. A. Enßlin E. Falgarone 16, 1 Y. Fantaye K. Ferrière 17 F. Finelli F. Forastieri M. Frailis A. A. Fraisse E. Franceschi A. Frolov S. Galeotta S. Galli K. Ganga 10 R. T. Génova-Santos T. Ghosh 18, * J. González-Nuevo K. M. Górski 19 A. Gruppuso J. E. Gudmundsson V. Guillet 18 W. Handley F. K. Hansen D. Herranz Z. Huang 20 A. H. Jaffe W. C. Jones E. Keihänen R. Keskitalo K. Kiiveri J. Kim N. Krachmalnicoff M. Kunz H. Kurki-Suonio J.-M. Lamarre 16 A. Lasenby M. Le Jeune 10 F. Levrier 16 M. Liguori P. B. Lilje V. Lindholm M. López-Caniego P. M. Lubin Y.-Z. Ma J. F. Macías-Pérez 13 G. Maggio D. Maino N. Mandolesi A. Mangilli 2 P. G. Martin E. Martínez-González S. Matarrese 21 J. D. Mcewen P. R. Meinhold A. Melchiorri 22 M. Migliaccio M.-A. Miville-Deschênes 23 D. Molinari A. Moneti 3 L. Montier 2 G. Morgante P. Natoli L. Pagano 18 D. Paoletti V. Pettorino 24 F. Piacentini G. Polenta J.-L. Puget 18 J. P. Rachen M. Reinecke M. Remazeilles 25 A. Renzi G. Rocha 19 C. Rosset 10 G. Roudier 16, 10 J. A. Rubiño-Martín B. Ruiz-Granados L. Salvati 18 M. Sandri 26 M. Savelainen D. Scott 27 J. D. Soler 28 L. D. Spencer J. A. Tauber D. Tavagnacco L. Toffolatti M. Tomasi 29 T. Trombetti J. Valiviita F. Vansyngel 18 B. van Tent 30 P. Vielva F. Villa N. Vittorio I. K. Wehus A. Zacchei A. Zonca
* Corresponding author
1 Astrophysique
LPENS (UMR_8023) - Laboratoire de physique de l'ENS - ENS Paris
Abstract : The study of polarized dust emission has become entwined with the analysis of the cosmic microwave background (CMB) polarization in the quest for the curl-like B-mode polarization from primordial gravitational waves and the low-multipole $E$-mode polarization associated with the reionization of the Universe. We used the new $Planck$ PR3 maps to characterize Galactic dust emission at high latitudes as a foreground to the CMB polarization and use end-to-end simulations to compute uncertainties and assess the statistical significance of our measurements. We present $Planck$ $EE$, $BB$, and $TE$ power spectra of dust polarization at 353 GHz for a set of six nested high-Galactic-latitude sky regions covering from 24 to 71% of the sky. We present power-law fits to the angular power spectra, yielding evidence for statistically significant variations of the exponents over sky regions and a difference between the values for the EE and BB spectra, which for the largest sky region are $\alpha_{EE}$ = −2.42 ± 0.02 and $\alpha_{BB}$ = −2.54 ± 0.02, respectively. The spectra show that the $TE$ correlation and $E/B$ power asymmetry discovered by Planck extend to low multipoles that were not included in earlier Planck polarization papers due to residual data systematics. We also report evidence for a positive $TB$ dust signal. Combining data from Planck and WMAP, we have determined the amplitudes and spectral energy distributions (SEDs) of polarized foregrounds, including the correlation between dust and synchrotron polarized emission, for the six sky regions as a function of multipole. This quantifies the challenge of the component-separation procedure that is required for measuring the low-ℓ reionization CMB E-mode signal and detecting the reionization and recombination peaks of primordial CMB B modes. The SED of polarized dust emission is fit well by a single-temperature modified black-body emission law from 353 GHz to below 70 GHz. For a dust temperature of 19.6 K, the mean dust spectral index for dust polarization is $\beta^P_d$ = 1.53±0.02. The difference between indices for polarization and total intensity is $\beta^P_d$ $- \beta^I_d$ = 0.05±0.03. By fitting multi-frequency cross-spectra between Planck data at 100, 143, 217, and 353 GHz, we examine the correlation of the dust polarization maps across frequency. We find no evidence for a loss of correlation and provide lower limits to the correlation ratio that are tighter than values we derive from the correlation of the 217- and 353 GHz maps alone. If the Planck limit on decorrelation for the largest sky region applies to the smaller sky regions observed by sub-orbital experiments, then frequency decorrelation of dust polarization might not be a problem for CMB experiments aiming at a primordial B-mode detection limit on the tensor-to-scalar ratio $r$ ≃ 0.01 at the recombination peak. However, the Planck sensitivity precludes identifying how difficult the component-separation problem will be for more ambitious experiments targeting lower limits on $r$.
Document type :
Journal articles
Complete list of metadatas

Cited literature [67 references]  Display  Hide  Download
Contributor : Edp Sciences <>
Submitted on : Friday, September 11, 2020 - 10:04:42 PM
Last modification on : Thursday, December 31, 2020 - 11:12:01 AM
Long-term archiving on: : Friday, December 4, 2020 - 5:48:46 PM


Publication funded by an institution


Distributed under a Creative Commons Attribution 4.0 International License



Y. Akrami, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, et al.. Planck 2018 results: XI. Polarized dust foregrounds. Astronomy and Astrophysics - A&A, EDP Sciences, 2020, 641, pp.A11. ⟨10.1051/0004-6361/201832618⟩. ⟨cea-02936944⟩



Record views


Files downloads