Difference between revisions of "Summary LFI"

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{{DISPLAYTITLE:Summary of LFI data characteristics}}
 
{{DISPLAYTITLE:Summary of LFI data characteristics}}
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The LFI performance are summarized in Table 1 below. All the details can be found in the LFI data processing paper {{PlanckPapers|planck2013-p02}}.
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Quantification of the performance of LFI is summarized in Table 1 below. All the details can be found in the LFI data processing paper {{PlanckPapers|planck2016-l02}}.  
  
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{| border="1" cellspacing="0" cellpadding="2" align="center"
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|+ '''Table 1. LFI performance parameters'''
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|-
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!scope="col"| Parameter
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!scope="col"| 30 GHz
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!scope="col"| 44 GHz
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!scope="col"| 70 GHz
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|-
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|width="320" | Centre frequency [GHz]
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|width="100" | 28.4
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|width="100" | 44.1
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|width="100" | 70.4
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|-
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|width="320" | Bandwidth [GHz]
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|width="100" | 9.89
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|width="100" | 10.72
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|width="100" | 14.90
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|-
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|width="320" | Scanning beam FWHM<sup>a</sup> [arcmin]
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|width="100" | 33.10
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|width="100" | 27.94
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|width="100" | 13.08
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|-
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|width="320" | Scanning beam ellipticity<sup>a</sup>
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|width="100" | 1.37
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|width="100" | 1.25
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|width="100" | 1.27
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|-
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|width="320" | Effective beam FWHM<sup>b</sup> [arcmin]
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|width="100" | 32.29
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|width="100" | 27.00
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|width="100" | 13.22
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|-
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|width="320" | White noise level in timelines<sup>c</sup> [&mu;K<sub>CMB</sub> s<sup>1/2</sup>]
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|width="100" | 147.9
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|width="100" | 174.0
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|width="100" | 151.9
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|-
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|width="320" | <i>f</i><sub>knee</sub><sup>c</sup> [mHz]
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|width="100" | 113.9
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|width="100" | 53.0
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|width="100" | 19.6
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|-
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|width="320" | 1/<i>f</i> slope<sup>c</sup>
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|width="100" | -0.92
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|width="100" | -0.88
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|width="100" | -1.20
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|-
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|width="320" | Overall calibration uncertainty<sup>d</sup> [%]
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|width="100" | 0.17
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|width="100" | 0.12
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|width="100" | 0.20
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|-
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|}
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 +
 
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<sup>a</sup> Determined by fitting Jupiter observations directly in the timelines.
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<sup>b</sup> Calculated from the main beam solid angle of the effective beam, &Omega;<sub>eff</sub> = mean(&Omega;). These values are used in the source extraction pipeline ({{PlanckPapers|planck2014-a35}}).
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<!-- {{PlanckPapers|planck2013-p05}} -->
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<sup>c</sup> Typical values derived from fitting noise spectra
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<sup>d</sup> difference between first and last iteration of the iterative calibration (for 30 and 44 GHz) or E2E 2015 result (for 70 GHz). In 2015 the calibration uncertainity was 0.35% and 0.26% at 30 and 44, respectively.
  
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<center>
 
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'''Table 1. Summary of the LFI performance parameters'''
 
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[[File:tab_perf2.jpg|thumb|center|600px|
 
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<math>^{ \rm a \, }</math> FWHM and ellipticity from scanning beam evaluated fitting Jupiter directly in the timelines. <math>\hspace{480mm} </math>
 
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<math>^{ \rm b \, }</math> FWHM from effective beam estimated from the main beam solid angle of the effective beam. Those are the values used in the source extraction pipeline {{PlanckPapers|planck2013-p05}}.
 
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<math>{\hspace{35mm}}</math>
 
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<math>^{ \rm c \, }</math> White noise per pixel computed from half-ring difference maps. Those values are within the 1% with the white noise sensitivity computed directly on the timelines, taking in account the actual mission time minus the manoeuvres and bad-science flagged data.
 
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]]
 
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</center>
 
  
 
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Latest revision as of 16:00, 5 July 2018

Quantification of the performance of LFI is summarized in Table 1 below. All the details can be found in the LFI data processing paper Planck-2020-A2[1].

Table 1. LFI performance parameters
Parameter 30 GHz 44 GHz 70 GHz
Centre frequency [GHz] 28.4 44.1 70.4
Bandwidth [GHz] 9.89 10.72 14.90
Scanning beam FWHMa [arcmin] 33.10 27.94 13.08
Scanning beam ellipticitya 1.37 1.25 1.27
Effective beam FWHMb [arcmin] 32.29 27.00 13.22
White noise level in timelinesc [μKCMB s1/2] 147.9 174.0 151.9
fkneec [mHz] 113.9 53.0 19.6
1/f slopec -0.92 -0.88 -1.20
Overall calibration uncertaintyd [%] 0.17 0.12 0.20


a Determined by fitting Jupiter observations directly in the timelines.

b Calculated from the main beam solid angle of the effective beam, Ωeff = mean(Ω). These values are used in the source extraction pipeline (Planck-2015-A26[2]).

c Typical values derived from fitting noise spectra

d difference between first and last iteration of the iterative calibration (for 30 and 44 GHz) or E2E 2015 result (for 70 GHz). In 2015 the calibration uncertainity was 0.35% and 0.26% at 30 and 44, respectively.


References[edit]

  1. ↑ Planck 2018 results. II. Low Frequency Instrument data processing, Planck Collaboration, 2020, A&A, 641, A2.
  2. ↑ Planck 2015 results. XXVI. The second Planck catalogue of compact sources, Planck Collaboration, 2016, A&A, 594, A26.

(Planck) Low Frequency Instrument

Full-Width-at-Half-Maximum

Cosmic Microwave background

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