Planck 2013 results

II. Low Frequency Instrument data processing

Jussi Varis, A. Zacchei (Corresponding Author), Planck Collaboration

Research output: Contribution to journalArticleScientificpeer-review

4 Citations (Scopus)

Abstract

We describe the data processing pipeline of the Planck Low Frequency Instrument (LFI) data processing centre (DPC) to create and characterize full-sky maps based on the first 15.5 months of operations at 30, 44, and 70 GHz. In particular, we discuss the various steps involved in reducing the data, from telemetry packets through to the production of cleaned, calibrated timelines and calibrated frequency maps. Data are continuously calibrated using the modulation induced on the mean temperature of the cosmic microwave background radiation by the proper motion of the spacecraft. Sky signals other than the dipole are removed by an iterative procedure based on simultaneous fitting of calibration parameters and sky maps. Noise properties are estimated from time-ordered data after the sky signal has been removed, using a generalized least squares map-making algorithm. A destriping code (Madam) is employed to combine radiometric data and pointing information into sky maps, minimizing the variance of correlated noise. Noise covariance matrices, required to compute statistical uncertainties on LFI and Planck products, are also produced. Main beams are estimated down to the ~-20 dB level using Jupiter transits, which are also used for the geometrical calibration of the focal plane.
Original languageEnglish
Article numberA2
Number of pages25
JournalAstronomy and Astrophysics
Volume571
DOIs
Publication statusPublished - 2014
MoE publication typeA1 Journal article-refereed

Fingerprint

sky
low frequencies
calibration
cosmic microwave background radiation
telemetry
proper motion
transit
Jupiter (planet)
Jupiter
spacecraft
dipoles
modulation
matrix
products
temperature

Keywords

  • cosmic background radiation
  • data analysis
  • cosmology
  • surveys

Cite this

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title = "Planck 2013 results: II. Low Frequency Instrument data processing",
abstract = "We describe the data processing pipeline of the Planck Low Frequency Instrument (LFI) data processing centre (DPC) to create and characterize full-sky maps based on the first 15.5 months of operations at 30, 44, and 70 GHz. In particular, we discuss the various steps involved in reducing the data, from telemetry packets through to the production of cleaned, calibrated timelines and calibrated frequency maps. Data are continuously calibrated using the modulation induced on the mean temperature of the cosmic microwave background radiation by the proper motion of the spacecraft. Sky signals other than the dipole are removed by an iterative procedure based on simultaneous fitting of calibration parameters and sky maps. Noise properties are estimated from time-ordered data after the sky signal has been removed, using a generalized least squares map-making algorithm. A destriping code (Madam) is employed to combine radiometric data and pointing information into sky maps, minimizing the variance of correlated noise. Noise covariance matrices, required to compute statistical uncertainties on LFI and Planck products, are also produced. Main beams are estimated down to the ~-20 dB level using Jupiter transits, which are also used for the geometrical calibration of the focal plane.",
keywords = "cosmic background radiation, data analysis, cosmology, surveys",
author = "Jussi Varis and A. Zacchei and {Planck Collaboration}",
note = "Project code: 18080",
year = "2014",
doi = "10.1051/0004-6361/201321550",
language = "English",
volume = "571",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",

}

Planck 2013 results : II. Low Frequency Instrument data processing. / Varis, Jussi; Zacchei, A. (Corresponding Author); Planck Collaboration.

In: Astronomy and Astrophysics, Vol. 571, A2, 2014.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Planck 2013 results

T2 - II. Low Frequency Instrument data processing

AU - Varis, Jussi

AU - Zacchei, A.

AU - Planck Collaboration

N1 - Project code: 18080

PY - 2014

Y1 - 2014

N2 - We describe the data processing pipeline of the Planck Low Frequency Instrument (LFI) data processing centre (DPC) to create and characterize full-sky maps based on the first 15.5 months of operations at 30, 44, and 70 GHz. In particular, we discuss the various steps involved in reducing the data, from telemetry packets through to the production of cleaned, calibrated timelines and calibrated frequency maps. Data are continuously calibrated using the modulation induced on the mean temperature of the cosmic microwave background radiation by the proper motion of the spacecraft. Sky signals other than the dipole are removed by an iterative procedure based on simultaneous fitting of calibration parameters and sky maps. Noise properties are estimated from time-ordered data after the sky signal has been removed, using a generalized least squares map-making algorithm. A destriping code (Madam) is employed to combine radiometric data and pointing information into sky maps, minimizing the variance of correlated noise. Noise covariance matrices, required to compute statistical uncertainties on LFI and Planck products, are also produced. Main beams are estimated down to the ~-20 dB level using Jupiter transits, which are also used for the geometrical calibration of the focal plane.

AB - We describe the data processing pipeline of the Planck Low Frequency Instrument (LFI) data processing centre (DPC) to create and characterize full-sky maps based on the first 15.5 months of operations at 30, 44, and 70 GHz. In particular, we discuss the various steps involved in reducing the data, from telemetry packets through to the production of cleaned, calibrated timelines and calibrated frequency maps. Data are continuously calibrated using the modulation induced on the mean temperature of the cosmic microwave background radiation by the proper motion of the spacecraft. Sky signals other than the dipole are removed by an iterative procedure based on simultaneous fitting of calibration parameters and sky maps. Noise properties are estimated from time-ordered data after the sky signal has been removed, using a generalized least squares map-making algorithm. A destriping code (Madam) is employed to combine radiometric data and pointing information into sky maps, minimizing the variance of correlated noise. Noise covariance matrices, required to compute statistical uncertainties on LFI and Planck products, are also produced. Main beams are estimated down to the ~-20 dB level using Jupiter transits, which are also used for the geometrical calibration of the focal plane.

KW - cosmic background radiation

KW - data analysis

KW - cosmology

KW - surveys

U2 - 10.1051/0004-6361/201321550

DO - 10.1051/0004-6361/201321550

M3 - Article

VL - 571

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - A2

ER -