J/A+A/481/411 submm point sources from the Archeops experiment (Desert+, 2008)
Submillimetre point sources from the Archeops experiment:
very cold clumps in the Galactic plane.
Desert F.-X., Macias-Perez J.F., Mayet F., Giardino G., Renault C.,
Aumont J., Benoit A., Bernard J.-P., Ponthieu N., Tristram M.
<Astron. Astrophys. 481, 411 (2008)>
=2008A&A...481..411D 2008A&A...481..411D
ADC_Keywords: Interstellar medium ; Millimetric/submm sources
Keywords: ISM: general - ISM: clouds - methods: data analysis -
cosmology: observations - submillimeter - catalogs
Abstract:
Archeops is a balloon-borne experiment, mainly designed to measure
the Cosmic Microwave Background (CMB) temperature anisotropies at high
angular resolution (∼12 arcminutes). By-products of the mission are
shallow sensitivity maps over a large fraction of the sky (about 30 %)
in the millimetre and submillimetre range at 143, 217, 353 and 545GHz.
From these maps, we produce a catalog of bright submillimetre point
sources.
We present in this paper the processing and analysis of the Archeops
point sources. Redundancy across detectors is the key factor allowing
us to distinguish glitches from genuine point sources in the 20
independent maps. We look at the properties of the most reliable point
sources, totalling 304. Fluxes range from 1 to 10000Jy (at the
frequencies covering 143 to 545GHz). All sources are either planets
(2) or of galactic origin. The longitude range is from 75 to
198-degrees. Some of the sources are associated with the well-known
Lynds Nebulae and HII compact regions in the galactic plane. A large
fraction of the sources have an IRAS counterpart. Except for Jupiter,
Saturn, the Crab and Cas A, all sources show a dust-emission-like
modified blackbody emission spectrum. Temperatures cover a range from
7 to 27K. For the coldest sources (T<10K), a steep nubeta emissivity
law is found with a surprising beta∼3 to 4. An inverse relationship
between T and beta is observed. The number density of sources at
353GHz with flux brighter than 100Jy is of the order of 1 per degree
of Galactic longitude. These sources will provide a strong check for
the calibration of the Planck HFI focal plane geometry as a complement
to planets. These very cold sources observed by Archeops should be
prime targets for mapping observations by the Akari and Herschel space
missions and ground-based observatories.
Description:
Table 3 gives coordinates and basic photometric properties. The name
of the source gives the galactic coordinates in degrees. Fluxes and
1-sigma errors are in Jy, assuming a Rayleigh-Jeans color and for the
4 frequencies of 143, 217, 353 and 545GHz. No available measurements
are quoted as (sigma=-1). Upper limits are quoted at the 2-sigma
level. The bright sources with an asterisk have positional
uncertainties larger than the nominal 4arcmin (1-sigma).
Table 4 gives the model fit parameters and associations. For each
point source, the emissivity exponent beta and temperature T are given
along with the reduced chi^2 value. When the fit is unsatisfactory,
beta11 (assuming a fixed temperature of 11K), or T2 (assuming a
fixed exponent index of 2) are provided instead. The associated Iras
source is given along with the far infrared fluxes. A star by the name
of the Iras counterpart indicates that the Iras source has the Iras
colors of an ultra-compact HII region. Then associations with a
commonly used name are given with Lynds Dark Nebulae, Bright Nebulae,
Sharpless and other common catalogs. Associations with HII regions
(with angular size le 10arcmin) from the catalogue by Paladini et al.
(2003, Cat. J/A+A/397/213) are also given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 105 302 Cloud position and fluxes
table4.dat 139 302 Cloud model fit parameters and associations
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See also:
J/A+A/397/213 : Galactic HII regions (Paladini+, 2003)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- [DMM2008] [1/302] Sequential number
5- 8 A4 --- --- [Arch]
9- 21 A13 --- Arch Arch name (GLLL.ll+BB.bb)
22 A1 --- n_Arch [*] * for positional uncertainty >4' (1sigma)
24- 25 I2 h RAh Right ascension (J2000)
27- 28 I2 min RAm Right ascension (J2000)
30- 33 F4.1 s RAs Right ascension (J2000)
35 A1 --- DE- Declination sign (J2000)
36- 37 I2 deg DEd Declination (J2000)
39- 40 I2 arcmin DEm Declination (J2000)
42- 43 I2 arcsec DEs Declination (J2000)
45 A1 --- l_F143 Limit flag on F143
46- 50 F5.1 Jy F143 Flux density at 143GHz
52- 54 F3.1 Jy e_F143 rms uncertainty on F143
56 A1 --- l_S/N143 Limit flag on S/N143
57- 59 I3 --- S/N143 Signal-to-noise ratio for F143
61 A1 --- l_F217 Limit flag on F217
62- 67 F6.1 Jy F217 Flux density at 217GHz
69- 72 F4.1 Jy e_F217 rms uncertainty on F217
74 A1 --- l_S/N217 Limit flag on S/N217
75- 77 I3 --- S/N217 Signal-to-noise ratio for F217
79 A1 --- l_F353 Limit flag on F353
80- 83 I4 Jy F353 ?=0 Flux density at 353GHz
85- 86 I2 Jy e_F353 ?=-1 rms uncertainty on F353
88 A1 --- l_S/N353 Limit flag on S/N353
89- 90 I2 --- S/N353 ?=0 Signal-to-noise ratio for F353
92 A1 --- l_F545 Limit flag on F545
93- 96 I4 Jy F545 ?=0 Flux density at 545GHz
98-100 I3 Jy e_F545 ?=-1 rms uncertainty on F545
102 A1 --- l_S/N545 Limit flag on F545
103-105 I3 --- S/N545 ?=0 Signal-to-noise ratio for F545
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [DMM2008] [1/302] Sequential number
5- 8 A4 --- --- [Arch]
9- 21 A13 --- Arch Arch name (GLLL.ll+BB.bb)
23- 26 F4.2 --- beta ? Emissivity exponent beta
28- 31 F4.2 --- e_beta ? rms uncertainty on beta
33- 37 F5.2 K T ? Temperature
39- 42 F4.2 K e_T ? rms uncertainty on T
44- 47 F4.2 --- chi2r ? Reduced chi2 value
49- 52 F4.2 --- beta11 ? Emissivity exponent beta for fixed T=11K
54- 57 F4.2 --- e_beta11 ? rms uncertainty on beta11
59- 63 F5.2 K T2 ? Temperature for fixed beta=2
65- 68 F4.2 K e_T2 ? rms uncertainty on T2
70- 80 A11 --- IRAS Associated IRAS source
81 A1 --- n_IRAS [*] * for IRAS source having IRAS colours of
an ultra-compact HII region
83- 89 F7.1 Jy F100um ? IRAS flux at 100um
91- 97 F7.1 Jy F60um ? IRAS flux at 60um
99-139 A41 --- Name(s) Associations with a commonly used name with
Lynds Dark Nebulae, Bright Nebulae,
Sharpless and other common catalogs
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Acknowledgements:
Francois-Xavier Desert, francois-xavier.desert(at)obs.ujf-grenoble.fr
(End) Patricia Vannier [CDS] 14-Feb-2008