J/MNRAS/458/3619 Planck ERCSC sources with 100 GHz flux excess (Chen+, 2016)
The bandmerged Planck Early Release Compact Source Catalogue:
probing sub-structure in the molecular gas at high Galactic latitude.
Chen X., Chary R., Pearson T.J., Mcgehee P., Fowler J.W., Helou G.
<Mon. Not. R. Astron. Soc., 458, 3619-3632 (2016)>
=2016MNRAS.458.3619C 2016MNRAS.458.3619C (SIMBAD/NED BibCode)
ADC_Keywords: Millimetric/submm sources ; Surveys ; Radio continuum
Keywords: radiation mechanisms: general - catalogues - surveys -
radio continuum: galaxies
Abstract:
The Planck Early Release Compact Source Catalogue (ERCSC) includes
nine lists of highly reliable sources, individually extracted at each
of the nine Planck frequency channels. To facilitate the study of the
Planck sources, especially their spectral behaviour across the
radio/infrared frequencies, we provide a 'bandmerged' catalogue of
the ERCSC sources. This catalogue consists of 15191 entries, with 79
sources detected in all nine frequency channels of Planck and 6818
sources detected in only one channel. We describe the bandmerging
algorithm, including the various steps used to disentangle sources in
confused regions. The multifrequency matching allows us to develop
spectral energy distributions of sources between 30 and 857GHz, in
particular across the 100GHz band, where the energetically important
CO J=1->0 line enters the Planck bandpass. We find ∼3σ-5σ
evidence for contribution to the 100GHz intensity from foreground CO
along the line of sight to 147 sources with |b|>{30deg}. The median
excess contribution is 4.5±0.9 per cent of their measured 100 GHz
flux density which cannot be explained by calibration or beam
uncertainties. This translates to 0.5±0.1K.km/s of CO which must be
clumped on the scale of the Planck 100GHz beam, i.e. ∼10-arcmin. If
this is due to a population of low-mass (∼15M☉) molecular gas
clumps, the total mass in these clumps may be more than 2000 M☉.
Further, high-spatial-resolution, ground-based observations of the
high-latitude sky will help shed light on the origin of this diffuse,
clumpy CO emission.
Description:
We have created a bandmerged catalogue of the Planck ERCSC in this
paper, and we have shown how confusing cases, arising from the varying
spatial resolution in the different bandpasses, can be handled in the
process. We used the catalogue to probe the spectral types of the
sources at different Planck frequencies. The flux densities in the
Planck 100GHz bandpass are contaminated by CO J=1=>0 emission. We
have shown that by simple interpolation between the 70 and 143GHz flux
densities of individual sources, we can estimate the flux-density
excess arising from the CO along the lines of sight.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 87 254 List of sources with 100 GHz flux excess in
the Planck ERCSC
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See also:
VIII/88 : Planck Early Release Compact Source Catalogue (Planck, 2011)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- --- [PLCKERC]
9- 22 A14 --- PLCKERC PLCKERC designation (GLL.ll+BB.bbb)
24- 25 I2 h RAh Right Ascension (J2000)
27- 28 I2 min RAm Right Ascension (J2000)
30- 31 I2 s RAs Right Ascension (J2000)
33 A1 --- DE- Declination sign (J2000)
34- 35 I2 deg DEd Declination (J2000)
37- 38 I2 arcmin DEm Declination (J2000)
40- 45 F6.2 Jy S70 70GHz flux density
47- 50 F4.2 Jy e_S70 Uncertainty to the 70 Hz flux density
52- 57 F6.2 Jy S100 100GHz flux density
59- 63 F5.2 Jy e_S100 Uncertainty to the 100GHz flux density
65- 70 F6.2 Jy S143 143GHz flux density
72- 75 F4.2 Jy e_S143 Uncertainty to the 143GHz flux density
77- 81 F5.2 Jy Sexcess Excess flux density at 100GHz
83- 87 F5.2 Jy e_Sexcess Uncertainty to the 100GHz excess flux density
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 17-Feb-2017