Catalogues

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Planck Catalogue of Compact Sources[edit]


Product description[edit]

Sky distribution of the PCCS sources at three different channels: 30GHz (pink circles), 143GHz (magenta circles) and 857GHz (green circles). The dimension of the circles is related to the brightness of the sources and the beam size of each channel.

The PCCS is a set of nine single-frequencies lists of sources extracted from the Planck nominal mission data. By definition its reliability is > 80% and a special effort was made to use simple selection procedures in order to facilitate statistical analyses. With a common detection method for all the channels and the additional three photometries, spectral analysis can also be done safely. The deeper completeness levels and, as a consequence, the higher number of sources compared with its predecessor the ERCSC, will allow the extension of previous studies to more sources and to fainter flux densities. The PCCS is the natural evolution of the ERCSC, but both lack polarization and multi-frequency information. Future releases will take advantage of the full mission data and they will contain information on properties of sources not available in this release, such as polarization, multi-frequency and variability.


Table 1: PCCS characteristics
Channel 30 44 70 100 143 217 353 545 857
Frequency [GHz] 28.4 44.1 70.4 100.0 143.0 217.0 353.0 545.0 857.0
Beam FWHMa [arcmin] 32.38 27.10 13.30 9.88 7.18 4.87 4.65 4.72 4.39
SNR threshold 4.0 4.0 4.0 4.6 4.7 4.8 4.9b/6.0c 4.7/7.0 4.9/7.0
# 1256 731 939 3850 5675 16070 17689 26472 35719
# (|b| > 30º) 572 258 332 845 1051 1901 2035 4164 7851
Flux density uncertainty [mJy] 109 198 149 61 38 35 74 132 189
Min flux densityd [mJy] 461 825 566 266 169 149 298 479 671
90% completeness [mJ] 575 1047 776 300 190 180 330 570 680
Position uncertaintye [arcmin] 1.8 2.1 1.4 1.0 0.7 0.7 0.8 0.5 0.4

a The Planck beams are described in (#planck2013-p02d; #planck2013-p03c). This table shows the values which were adopted for the PCCS (derived from the effective beams).

b In the extragalactic zone (48% of the sky; see Fig. 2 in #planck2013-p05).

c In the Galactic zone (52% of the sky; see Fig. 2 in #planck2013-p05).

d Minimum flux density of the catalogue at |b| > 30º after excluding the 10% faintest sources.

e Positional uncertainty derived by comparison with PACO sample (Massardi et al. 2011; Bonavera et al. 2011; Bonaldi et al. 2013) up to 353 GHz and with Herschel samples (HRS, KINGFISH, HeViCS, H-ATLAS) in the other channels.

Before using the PCCS, please read the Cautionary Notes in the PCCS general description section.

For full details, see paper #planck2013-p05.

Production process[edit]

For a description of the production and validation processes of the PCCS see the corresponding section.

Inputs[edit]

The data obtained from the Planck nominal mission between 2009 August 13 and 2010 November 27, corresponding to operational days 91--636, have been processed into full-sky maps by the HFI and LFI Data Processing Centres (DPCs). A description of the processing can be found in #planck2013-p02,#planck2013-p03. The data consist of two complete sky surveys and 60% of the third survey. This implies that the flux densities of sources obtained from the nominal mission maps are the average of at least two observations. The nine Planck frequency channel maps are used as input to the source detection pipelines. For the high-frequency channels, 353, 545 and 857 GHz, the model of the Zodiacal Light Emission (ZLE) (?) has been subtracted from the maps before detecting the sources. The relevant properties of the frequency maps and main parameters used to generate the catalogues are summarized in Table 1.

The input data used to generate this product are the following:


Related products[edit]

Other products that are related and share some commonalities with the product being described here are the other catalogues:

  1. ERCSC
  2. SZ catalogue

File names[edit]

COM_PCCS_030_R1.20.fits
COM_PCCS_044_R1.20.fits
COM_PCCS_070_R1.20.fits
COM_PCCS_100_R1.10.fits
COM_PCCS_143_R1.10.fits
COM_PCCS_217_R1.10.fits
COM_PCCS_353_R1.10.fits
COM_PCCS_545_R1.10.fits
COM_PCCS_857_R1.10.fits

Meta Data[edit]

The PCCS source list in each frequency is structured as a FITS binary table having one row for each detected source.

The FITS primary header will have the following structure:

FITS primary header
FITS Keyword Data Type Units Description
INSTRUME String LFI or HFI
VERSION String Version of PCCS
DATE String Date file created:yyyy-mm-dd
ORIGIN String Name of organization responsible for the data (LFI-DPCHFI-DPC)
TELESCOP String PLANCK
CREATOR String Pipeline Version
DATE-OBS String days Start-up time of the survey: yyyy-mm-dd
DATE-END String days Ending time of the survey: yyyy-mm-dd


The Fits extension is composed by several columns described below:

FITS header
Column Name Data Type Units Description
Identification
NAME String Source name – see Note 1
Source Position
GLON Real*8 degrees Galactic longitude based on extraction algorithm
GLAT Real*8 degrees Galactic latitude based on extraction algorithm
RA Real*8 degrees Right ascension (J2000) transformed from (GLON,GLAT)
DEC Real*8 degrees Declination (J2000) transformed from (GLON,GLAT)
Photometry
DETFLUX Real*4 mJy Flux density of source as determined by detection method
DETFLUX_ERR Real*4 mJy Uncertainty (1 sigma) in derived flux density from detection method
APERFLUX Real*4 mJy Flux density of source as determined from the aperture photometry
APERFLUX_ERR Real*4 mJy Uncertainty (1 sigma) in derived flux density from the aperture photometry
PSFFLUX Real*4 mJy Flux density of source as determined from PSF fitting
PSFFLUX_ERR Real*4 mJy Uncertainty (1 sigma) in derived flux density from PSF fitting
GAUFLUX Real*4 mJy Flux density of source as determined from 2-D Gaussian fitting
GAUFLUX_ERR Real*4 mJy Uncertainty (1 sigma) in derived flux density from 2-D Gaussian fitting
GAU_SEMI1 Real*4 arcmin Gaussian fit along axis 1 (FWHM; see Note 4 for axis definition)
GAU_SEMI1_ERR Real*4 arcmin Uncertainty (1 sigma) in derived Gaussian fit along axis 1
GAU_SEMI2 Real*4 arcmin Gaussian fit along axis 2 (FWHM)
GAU_SEMI2_ERR Real*4 arcmin Uncertainty (1 sigma) in derived Gaussian fit along axis 2
GAU_THETA Real*4 deg Gaussian fit orientation angle counting anti-clockwise from the y-axis
GAU_THETA_ERR Real*4 deg Uncertainty (1 sigma) in derived gaussian fit orientation angle
GAU_FWHM_EFF Real*4 arcmin Gaussian fit effective FWHM
Flags and validation
EXTENDED Integer*2 Flag indicated that source is extended
CIRRUS_N Integer*2 Number of sources detected at 857 GHz within 1 degree
EXT_VAL Integer*2 Flag indicated external validation - see Note 2
ERCSC String Name of the ERCSC counterpart if any
ONLY 857 GHz Catalogue
APERFLUX_217 Real*4 mJy Source flux density at 217 GHz (best estimation) of the object detected at 857
APERFLUX_ERR_217 Real*4 mJy Uncertainty in source flux density at 217 GHz
APERFLUX_353 Real*4 mJy Source flux density at 353 GHz (best estimation) of the object detected at 857
APERFLUX_ERR_353 Real*4 mJy Uncertainty in source flux density at 353 GHz
APERFLUX_545 Real*4 mJy Source flux density at 545 GHz (best estimation) of the object detected at 857
APERFLUX_ERR_545 Real*4 mJy Uncertainty in source flux density at 545 GHz

Note 1.- Source names consist of a prefix and a position. The prefix used is PCCS1 fff for the catalogue at fff GHz. The position is in Galactic coordinates and specified as "Glll.ll±bb.bb" where the (l,b) values are truncated to two decimal places.

For example, a source detected at (l,b) = (120.237, 4.231) in the 545 GHz Planck map would be labelled PCCS1 545 G120.23±04.23.

Note 2.- The EXTENDED flag has the value of 0 if the source is compact and the value of 1 is it extended. The source size is determined by the geometric mean of the Gaussian fit FWHMs, with the criteria for extension being sqrt(GAU_FWHMMAJ * GAU_FWHMIN) > 1.5 times the beam FWHM.

Note 3.- The EXT_VAL flag takes the value of 0, 1, or 2, based on the following conditions:

  • 2 – The source has a clear counterpart in one of the catalogues considered as ancillary data.
  • 1 – The source has no clear counterpart in one of the ancillary catalogues but it has been detected by the internal multi-frequency method (LFI channels) or match with neighbouring frequencies, above or below (HFI channel's).
  • 0 – The source has no clear counterpart in one of the ancillary catalogues and it has not been detected by the internal multi-frequency method or neighbouring frequencies.

Note 4.- The x axis is defined for each source as parallel to the constant colatitude line, with the same direction as the longitude. Therefore the position angles are measured anticlockwise from the y axis.

Below an example of the header.


SZ catalogues[edit]


The Planck SZ catalogue is constructed as described in SZ catalogue and in section 2 of #planck2013-p05a.

Three pipelines are used to detect SZ clusters: two independent implementations of the Matched Multi-Filter (MMF1 and MMF3), and PowellSnakes (PwS). The main catalogue is constructed as the union of the catalogues from the three detection methods. The individual catalogues are provided for the expert user in order to assess the consistency of the pipelines. The completeness and reliability of the catalogues have been assessed through internal and external validation as described in sections 3-6 of #planck2013-p05a.

The union catalogue contains the coordinates and the signal-to-noise ratio of the detections and a summary of the external validation information, including external identification of a cluster and its redshift if it is available.

The individual catalogues contain the coordinates and the signal-to-noise ratio of the detections, and information on the size and flux of the detections. The entries are cross-referenced to the detections in the union catalogue.

The size of a detection is given in terms of the scale size, $\theta_\mathrm{s}$, and the flux is given in terms of the total integrated Comptonization parameter, $Y = Y_{5r_{500}}$. The parameters of the GNFW profile assumed by the detection pipelines is written in the headers in the catalogues. For the sake of convenience, the conversion factor from $Y$ to $Y_{500}$ is also written in the header.

The full information on the degeneracy between $\theta_\mathrm{s}$ and $Y$ is included in the individual catalogues in the form of the two-dimensional probability distribution for each detection. It is computed on a well-sampled grid to produce a two-dimensional image for each detection. The degeneracy information is provided in this form so it can be combined with a model or external data to produce tighter constraints on the parameters.


Union Catalogue[edit]

The union catalogue is contained in a file called COM_PCCS_SZ-union_Rx.xx.fits, where x.xx is the release number.

Primary HDU[edit]

The primary header contains the following keywords:


FITS Keyword Data Type Units Description
INSTRUME String Instrument.
VERSION String Version of catalogue.
DATE String Date file created: yyyy-mm-dd.
ORIGIN String Name of organization responsible for the data.
TELESCOP String PLANCK.
CREATOR String Pipeline version.
DATE-OBS String Start time of the survey: yyyy-mm-dd.
DATE-END String End time of the survey: yyyy-mm-dd.
PROCVER String Data version.
PP_ALPHA Real*4 GNFW pressure profile $\alpha$ parameter.
PP_BETA Real*4 GNFW pressure profile $\beta$ parameter.
PP_GAMMA Real*4 GNFW pressure profile $\gamma$ parameter.
PP_C500 Real*4 GNFW pressure profile $c_{500}$ parameter.
PP_Y2YFH Real*4 Conversion factor from $Y$ to $Y_{500}$.


First extension HDU[edit]

The first FITS extension HDU contains a binary table with the following columns:


Column Name Data Type Units Description
INDEX Int*4 Index. Used to cross-reference with individual catalogues.
NAME String Source name of format PSZ1 Glll.ll±bb.bb where (l,b) are the Galactic coordinates. The coordinates are truncated to 2 decimal places.
GLON Real*8 degrees Galactic longitude.
GLAT Real*8 degrees Galactic latitude.
RA Real*8 degrees Right ascension (J2000) transformed from (GLON,GLAT).
DEC Real*8 degrees Declination (J2000) transformed from (GLON,GLAT).
POS_ERR Real*4 arcmin Position uncertainty (95% confidence interval).
SNR Real*4 Signal-to-noise ratio of the detection.
PIPELINE Int*4 Pipeline from which union information is taken: 1= MMF1; 2 = MMF3; 3 = PwS.
PIPE_DET Int*4 Pipelines which detect this object. The three least significant decimal digits are used to represent detection or non-detection by the pipelines. Order of the digits: hundreds = MMF1; tens = MMF3; units = PwS. If it is detected then the corresponding digit is set to 1, otherwise it is set to 0.
PCCS Bool Indicates whether detection matches any PCCS source.
VALIDATION Int*4 External validation status: 1 = candidate of class 1; 2 = candidate of class 2; 3 = candidate of class 3; 10 = Planck cluster confirmed by follow-up; 20 = known cluster.
ID_EXT String External identifier of cluster.
REDSHIFT Real*4 Redshift of cluster.
COSMO Bool Indicates whether a detection is in the cosmology sample.
COMMENT Bool Indicates whether a detection has a comment in the associated text file (see below).


Comments[edit]

The comments on the detections in the catalogue are contained in a text file called COM_PCCS_SZ-union_comments_R1.11.txt where x.xx is the release number.

The file contains one line for each detection in the union catalogue with COMMENT = T. The line starts with the INDEX and NAME of the detection to facilitate cross-referencing. The remainder of the line is the comment on that detection.

Mask[edit]

The mask used to construct the catalogue is contained in a file called COM_PCCS_SZ-unionMask_2048_Rx.xx.fitswhere x.xx is the release number.


Individual Catalogues[edit]

The individual pipeline catalogues are contained in FITS files called COM_PCCS_SZ-pipeline_Rx.xx.fits, where pipeline is the name of the pipeline (MMF1, MMF3, or PwS) and x.xx is the release number.


Primary HDU[edit]

The FITS primary header contains the following keywords:


FITS Keyword Data Type Units Description
INSTRUME String Instrument.
VERSION String Version of catalogue.
DATE String Date file created: yyyy-mm-dd.
ORIGIN String Name of organization responsible for the data.
TELESCOP String PLANCK.
CREATOR String Pipeline version.
DATE-OBS String Start time of the survey: yyyy-mm-dd.
DATE-END String End time of the survey: yyyy-mm-dd.
PROCVER String Data version.
PP_ALPHA Real*4 GNFW pressure profile $\alpha$ parameter.
PP_BETA Real*4 GNFW pressure profile $\beta$ parameter.
PP_GAMMA Real*4 GNFW pressure profile $\gamma$ parameter.
PP_C500 Real*4 GNFW pressure profile $c_{500}$ parameter.
PP_Y2YFH Real*4 Conversion factor from $Y$ to $Y_{500}$.
PIPELINE String Name of detection pipeline.


First extension HDU[edit]

The first extension HDU contains a binary table with the following columns:


Column Name Data Type Units Description
INDEX Int*4 Index from union catalogue.
NAME String Source name from union catalogue of format PSZ1 Glll.ll±bb.bb where (l, b) are the Galactic coordinates. The coordinates are truncated to 2 decimal places.
GLON Real*8 degrees Galactic longitude.
GLAT Real*8 degrees Galactic latitude.
RA Real*8 degrees Right ascension (J2000) transformed from (GLON,GLAT).
DEC Real*8 degrees Declination (J2000) transformed from (GLON,GLAT).
POS_ERR Real*4 arcmin Position uncertainty (95% confidence interval).
SNR Real*4 Signal-to-noise ratio of the detection.
SNR_COMPAT Real*4 Signal-to-noise ratio of the detection in compatibility mode. For PwS, this is the S/N evaluated in a manner compatible with the MMF pipelines. For MMF1 and MMF3, it is identical to SNR.
TS_MIN Real*4 Minimum value of $\theta_\mathrm{s}$ in grid in second extension HDU (see below).
TS_MAX Real*4 Maximum value of $\theta_\mathrm{s}$ in grid in second extension HDU (see below).
Y_MIN Real*4 Minimum value of $Y$ in grid in second extension HDU (see below).
Y_MIN Real*4 Maximum value of $Y$ in grid in second extension HDU (see below).
Second extension HDU[edit]

The second extension HDU contains a three-dimensional image with the two-dimensional probability distribution in $\theta_\mathrm{s}$ and $Y$ for each detection. The probability distributions are evaluated on a 256 × 256 linear grid between the limits specified in the first extension HDU. The limits are determined independently for each detection. The dimension of the 3D image is 256 × 256 × n, where n is the number of detections in the catalogue. The first dimension is $\theta_\mathrm{s}$ and the second dimension is $Y$.


References[edit]

<biblio force=false>

  1. References

</biblio>

Early Release Compact Source Catalog

Full-Width-at-Half-Maximum

(Planck) High Frequency Instrument

(Planck) Low Frequency Instrument

Flexible Image Transfer Specification

Data Processing Center

Sunyaev-Zel'dovich