Catalogues

The Catalogue of Compact Sources

---

Product description

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

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

Inputs

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:

• frequency maps
• RIMO
• effective beams

Related products

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

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

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-DPC – HFI-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.

The SZ catalogues

---

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

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

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

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

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

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

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

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

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

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 $Y$.

The ERCSC

---

The Plank Early Release Compact Source Catalogue was the first Planck product to be publicly released in Jan 2011. It was produced with a very rapid turnaround to facilitate follow-up observations with existing cryogenic observatories such as Herschel. It contained a list of all high reliability sources, both Galactic and extragalactic, that were derived from the first all sky coverage by Planck. The data that went into the ERCSC comprised all observations undertaken between 13 August 2009 and 6 June 2010, corresponding to Planck operational days 91−389. Since the Planck scan strategy results in the entire sky being observed every 6 months, the data considered in the ERCSC release corresponded to the first sky coverage and 60% of the second sky coverage. The goals on photometric accuracy were 30% while the positional accuracy goal translated to a positional root mean square (RMS) uncertainty that is less than 1/5 of the beam full width at half maximum (FWHM).

The ERCSC consisted of single frequency source lists, one at each of the nine Planck frequencies. The number of sources in the lists range from 705 at 30 GHz to 8988 at 857 GHz. No attempt was made to cross-match the sources from the different frequencies due to the wide range of spatial resolutions (33 arcmin at 30 GHz to 4.3 arcmin at 857 GHz) spanned by Planck. Two additional catalogues which consisted of a list of Cold Cores of interstellar molecular clouds within the Galaxy and a list of galaxy clusters detected through the Sunyaev- Zel’dovich effect, were provided. These consisted of candidate sources that were detected using multifrequency algorithms that use the distinct spectral signature of such sources through the Planck frequency channels. The early Cold Cores (ECC) list comprised of 915 sources while the early Sunyaev-Zel'dovich (ESZ) effect detected cluster list consisted of 189 sources. In all, there are more than 15000 unique sources in these early catalogues.

In order to generate the ERCSC, four source detection algorithms were run as part of the ERCSC pipeline. A Monte-Carlo algorithm based on the injection and extraction of artificial sources into the Planck maps was implemented to select reliable sources among all extracted candidates such that the cumulative reliability of the catalogue is >90%. Reliability is defined as the fraction of sources in the catalog which have measured flux densities which are within 30% of their true flux density. There is no requirement on completeness for the ERCSC. As a result of the Monte-Carlo assessment of reliability of sources from the different techniques, an implementation of the PowellSnakes source extraction technique was used at the five frequencies between 30 and 143GHz while the SExtractor technique was used between 217 and 857GHz. The 10σ photometric flux density limit of the catalogue at |b| > 30 deg is 0.49, 1.0, 0.67, 0.5, 0.33, 0.28, 0.25, 0.47 and 0.82 Jy at each of the nine frequencies between 30 and 857GHz. Sources which are up to a factor of ~2 fainter than this limit, and which are present in "clean" regions of the Galaxy where the sky background due to emission from the interstellar medium is low, are included in the ERCSC if they meet the high reliability criterion. The sensitivity of the ERCSC is shown in the figure below. The Planck ERCSC sources have known associations to stars with dust shells, stellar cores, radio galaxies, blazars, infrared luminous galaxies and Galactic interstellar medium features. A significant fraction of unclassified sources are also present in the catalogs.

The multifrequency information from Planck allows some basic classification of the sources to be undertaken. In the Galactic plane, at frequencies below 100 GHz, the majority of the sources are dominated by synchrotron or free-free emission. At the higher frequencies, the sources are almost exclusively dominated by thermal dust emission. At high Galactic latitudes however, the synchrotron sources dominate the source counts to 217 GHz with dusty sources being the primary source population at 353 GHz and higher. Recent attempts to classify a subset of the Planck 857 GHz sources at high latitudes based on cross-correlations with sources in other catalogs such as WISE and SDSS, found that almost half of them are associated with stars and low-redshift galaxies while a significant fraction (44%) might be interstellar medium features (Johnson et al 2013, AAS, 22135218J).

Full details on the construction, contents and usage of the ERCSC, ECC and ESZ catalogues can be found in Planck Early Results VII, VIII and XXIII (Planck Collaboration 2011, A&A, A7, A8 and A23 respectively).

Figure: The Planck ERCSC flux density limit, quanitfied as the faintest ERCSC source at |b|<10 deg (dashed black line) and at |b|>30 deg (solid black line), is shown relative to other wide area surveys (From Planck Collaboration 2011, A&A, 536, A7). Also shown are spectra of known sources of foreground emission as red lines. The ERCSC sensitivity is worse in the Galactic plane due to the strong contribution of ISM emission, especially at submillimeter wavelengths. At face value, the WMAP and Planck flux density limits appear to be comparable at the lowest frequencies, but the Planck ERCSC is much more complete as discussed in Planck Collaboration (2011).

References

<biblio force=false>

1. References

</biblio>