Planck 2013 results

XII. Diffuse component separation

Planck Collaboration

Research output: Contribution to journalArticleScientificpeer-review

46 Citations (Scopus)

Abstract

Planck has produced detailed all-sky observations over nine frequency bands between 30 and 857 GHz. These observations allow robust reconstruction of the primordial cosmic microwave background (CMB) temperature fluctuations over nearly the full sky, as well as new constraints on Galactic foregrounds, including thermal dust and line emission from molecular carbon monoxide (CO). This paper describes the component separation framework adopted by Planck for many cosmological analyses, including CMB power spectrum determination and likelihood construction on large angular scales, studies of primordial non-Gaussianity and statistical isotropy, the integrated Sachs-Wolfe effect, gravitational lensing, and searches for topological defects. We test four foreground-cleaned CMB maps derived using qualitatively different component separation algorithms. The quality of our reconstructions is evaluated through detailed simulations and internal comparisons, and shown through various tests to be internally consistent and robust for CMB power spectrum and cosmological parameter estimation up to l = 2000. The parameter constraints on CDM cosmologies derived from these maps are consistent with those presented in the cross-spectrum based Planck likelihood analysis. We choose two of the CMB maps for specific scientific goals. We also present maps and frequency spectra of the Galactic low-frequency, CO, and thermal dust emission. The component maps are found to provide a faithful representation of the sky, as evaluated by simulations, with the largest bias seen in the CO component at 3%. For the low-frequency component, the spectral index varies widely over the sky, ranging from about ß = -4 to - 2. Considering both morphology and prior knowledge of the low frequencycomponents, the index map allows us to associate a steep spectral index (ß< -3.2) with strong anomalous microwave emission, corresponding to a spinning dust spectrum peaking below 20 GHz, a flat index of ß> -2.3 with strong free-free emission, and intermediate values with synchrotron emission.
Original languageEnglish
Article numberA12
Number of pages31
JournalAstronomy and Astrophysics
Volume571
DOIs
Publication statusPublished - 2014
MoE publication typeA1 Journal article-refereed

Fingerprint

sky
microwaves
carbon monoxide
dust
power spectra
low frequencies
microwave emission
gravitational effects
isotropy
metal spinning
simulation
defect
microwave
synchrotrons
index
defects
temperature
test

Keywords

  • cosmic background radiation

Cite this

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title = "Planck 2013 results: XII. Diffuse component separation",
abstract = "Planck has produced detailed all-sky observations over nine frequency bands between 30 and 857 GHz. These observations allow robust reconstruction of the primordial cosmic microwave background (CMB) temperature fluctuations over nearly the full sky, as well as new constraints on Galactic foregrounds, including thermal dust and line emission from molecular carbon monoxide (CO). This paper describes the component separation framework adopted by Planck for many cosmological analyses, including CMB power spectrum determination and likelihood construction on large angular scales, studies of primordial non-Gaussianity and statistical isotropy, the integrated Sachs-Wolfe effect, gravitational lensing, and searches for topological defects. We test four foreground-cleaned CMB maps derived using qualitatively different component separation algorithms. The quality of our reconstructions is evaluated through detailed simulations and internal comparisons, and shown through various tests to be internally consistent and robust for CMB power spectrum and cosmological parameter estimation up to l = 2000. The parameter constraints on CDM cosmologies derived from these maps are consistent with those presented in the cross-spectrum based Planck likelihood analysis. We choose two of the CMB maps for specific scientific goals. We also present maps and frequency spectra of the Galactic low-frequency, CO, and thermal dust emission. The component maps are found to provide a faithful representation of the sky, as evaluated by simulations, with the largest bias seen in the CO component at 3{\%}. For the low-frequency component, the spectral index varies widely over the sky, ranging from about {\ss} = -4 to - 2. Considering both morphology and prior knowledge of the low frequencycomponents, the index map allows us to associate a steep spectral index ({\ss}< -3.2) with strong anomalous microwave emission, corresponding to a spinning dust spectrum peaking below 20 GHz, a flat index of {\ss}> -2.3 with strong free-free emission, and intermediate values with synchrotron emission.",
keywords = "cosmic background radiation",
author = "Jussi Varis and M. Ashdown and {Planck Collaboration}",
note = "LIS: OA issue CO:U Planck Collaboration CA2: BA1141 Project code: 18080 PGN: 31 p. ISI: ASTRONOMY & ASTROPHYSICS",
year = "2014",
doi = "10.1051/0004-6361/201321580",
language = "English",
volume = "571",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",

}

Planck 2013 results : XII. Diffuse component separation. / Planck Collaboration.

In: Astronomy and Astrophysics, Vol. 571, A12, 2014.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Planck 2013 results

T2 - XII. Diffuse component separation

AU - Varis, Jussi

AU - Ashdown, M.

AU - Planck Collaboration

N1 - LIS: OA issue CO:U Planck Collaboration CA2: BA1141 Project code: 18080 PGN: 31 p. ISI: ASTRONOMY & ASTROPHYSICS

PY - 2014

Y1 - 2014

N2 - Planck has produced detailed all-sky observations over nine frequency bands between 30 and 857 GHz. These observations allow robust reconstruction of the primordial cosmic microwave background (CMB) temperature fluctuations over nearly the full sky, as well as new constraints on Galactic foregrounds, including thermal dust and line emission from molecular carbon monoxide (CO). This paper describes the component separation framework adopted by Planck for many cosmological analyses, including CMB power spectrum determination and likelihood construction on large angular scales, studies of primordial non-Gaussianity and statistical isotropy, the integrated Sachs-Wolfe effect, gravitational lensing, and searches for topological defects. We test four foreground-cleaned CMB maps derived using qualitatively different component separation algorithms. The quality of our reconstructions is evaluated through detailed simulations and internal comparisons, and shown through various tests to be internally consistent and robust for CMB power spectrum and cosmological parameter estimation up to l = 2000. The parameter constraints on CDM cosmologies derived from these maps are consistent with those presented in the cross-spectrum based Planck likelihood analysis. We choose two of the CMB maps for specific scientific goals. We also present maps and frequency spectra of the Galactic low-frequency, CO, and thermal dust emission. The component maps are found to provide a faithful representation of the sky, as evaluated by simulations, with the largest bias seen in the CO component at 3%. For the low-frequency component, the spectral index varies widely over the sky, ranging from about ß = -4 to - 2. Considering both morphology and prior knowledge of the low frequencycomponents, the index map allows us to associate a steep spectral index (ß< -3.2) with strong anomalous microwave emission, corresponding to a spinning dust spectrum peaking below 20 GHz, a flat index of ß> -2.3 with strong free-free emission, and intermediate values with synchrotron emission.

AB - Planck has produced detailed all-sky observations over nine frequency bands between 30 and 857 GHz. These observations allow robust reconstruction of the primordial cosmic microwave background (CMB) temperature fluctuations over nearly the full sky, as well as new constraints on Galactic foregrounds, including thermal dust and line emission from molecular carbon monoxide (CO). This paper describes the component separation framework adopted by Planck for many cosmological analyses, including CMB power spectrum determination and likelihood construction on large angular scales, studies of primordial non-Gaussianity and statistical isotropy, the integrated Sachs-Wolfe effect, gravitational lensing, and searches for topological defects. We test four foreground-cleaned CMB maps derived using qualitatively different component separation algorithms. The quality of our reconstructions is evaluated through detailed simulations and internal comparisons, and shown through various tests to be internally consistent and robust for CMB power spectrum and cosmological parameter estimation up to l = 2000. The parameter constraints on CDM cosmologies derived from these maps are consistent with those presented in the cross-spectrum based Planck likelihood analysis. We choose two of the CMB maps for specific scientific goals. We also present maps and frequency spectra of the Galactic low-frequency, CO, and thermal dust emission. The component maps are found to provide a faithful representation of the sky, as evaluated by simulations, with the largest bias seen in the CO component at 3%. For the low-frequency component, the spectral index varies widely over the sky, ranging from about ß = -4 to - 2. Considering both morphology and prior knowledge of the low frequencycomponents, the index map allows us to associate a steep spectral index (ß< -3.2) with strong anomalous microwave emission, corresponding to a spinning dust spectrum peaking below 20 GHz, a flat index of ß> -2.3 with strong free-free emission, and intermediate values with synchrotron emission.

KW - cosmic background radiation

U2 - 10.1051/0004-6361/201321580

DO - 10.1051/0004-6361/201321580

M3 - Article

VL - 571

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - A12

ER -