J/AJ/168/203 Dust clouds masses, color excesses and distances (Sun+, 2024)
Identification and distance measurement of dust clouds at high latitude by a
clustering hierarchical algorithm.
Sun M., Jiang B., Guo H., Cui W.
<Astron. J., 168, 203 (2024)>
=2024AJ....168..203S 2024AJ....168..203S
ADC_Keywords: Molecular clouds; Cross identifications; Extinction;
Ultraviolet; Radio sources; Optical; Interstellar medium
Keywords: Interstellar dust extinction ; High latitude field ;
Distance measure ; Ultraviolet extinction ; Molecular clouds
Abstract:
We present a catalog of dust clouds at high Galactic latitude based on
the Planck 857GHz dust emission data. Using a clustering hierarchical
algorithm, 315 dust clouds at high Galactic latitudes are identified.
Additionally, using the optical and ultraviolet extinction of 4million
and 1 million stars, respectively, provided by Sun+ 2021ApJS..254...38S 2021ApJS..254...38S,
we derive the distances and physical properties for 190 high Galactic
latitude dust clouds and the ultraviolet excess ratios for 165 of
them. Through the study of color excess ratios, this work confirms
that molecular clouds with large Galactic distances and low extinction
likely have a higher proportion of small-sized dust grains. In
addition, clouds with well-defined distances in the catalog are used
to trace the Local Bubble, showing good consistency with the boundary
of the Local Bubble from the literature.
Description:
The Planck 857GHz map (Planck Coll.+, 2020A&A...641A...1P 2020A&A...641A...1P) is used for
dust cloud identification. The map has a spatial resolution of
approximately 4.22'.
The extinction values are taken from Sun+ (2021ApJS..254...38S 2021ApJS..254...38S), who
provided the values of the color excesses, EBP,RP between the
Gaia/BP (blue) and Gaia/RP (red) bands and ENUV,BP between the
Galaxy Evolution Explorer (GALEX) near-ultraviolet (NUV) and Gaia/BP
bands for over 4 million and 1 million dwarf stars, respectively,
which are mainly located at high latitudes. Combining stellar
parameters from the LAMOST (Luo+ 2015, V/146) and GALAH
(Buder+ 2021, J/MNRAS/506/150) spectroscopic surveys and photometric
data (GBP, GRP, and NUV) from Gaia/EDR3 (Gaia Coll.+ 2021, I/350)
and GALEX (Bianchi+ 2014, 2014Ap&SS.354..103B 2014Ap&SS.354..103B) and using the blue-edge
method (Jian+ 2017, 2017AJ....153....5J 2017AJ....153....5J; Sun+ 2018, J/ApJ/861/153),
the average error of EBP,RP and ENUV,BP is ∼0.01mag and 0.1mag,
respectively. The stars with the color excess of
Sun+ (2021ApJS..254...38S 2021ApJS..254...38S) and distance from Gaia/EDR3 will be the
tracers for the extinction and distance of the high-latitude clouds.
This work estimates the gas cloud masses from HI and CO observations.
For the HI observation, the HI4PI survey, which is based on the
completed EBHIS and the third revision of the GASS, is chosen
(HI4PI Collaboration+ 2016, J/A+A/594/A116). The HI4PI survey has an
angular resolution of 16.2' and a sensitivity of 43mK. For the CO
observation, the Planck survey is chosen, and the type 2 data are used
(Planck Collaboration+ 2014, 2014A&A...571A..13P 2014A&A...571A..13P). Type 2 utilizes the
intensity maps from multiple channels to isolate the contribution of
CO from other astrophysical emission sources.
Surveys and instruments details:
The Planck satellite scanned the microwave and submillimetre sky
continuously between 12 August 2009 and 23 October 2013.
Gaia DR3 (I/350) data are based on data collected from space between
25 July 2014 and 28 May 2017.
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope
(LAMOST, V/164) is in the Hebei Province in China. Its survey includes
both the pilot survey, which started in October 2011 and ended in June
2012, and the regular survey, which started in September 2012 and
completed its first year of operation in June 2013.
The GALactic Archaeology with HERMES (GALAH, J/MNRAS/506/150) survey
is a large observing program using the HERMES instrument with the
Anglo-Australian Telescope situated at the Siding Spring Observatory,
Australia. GALAH+ DR3 includes all data taken between November 2013
and February 2019.
The Galaxy Evolution Explorer (GALEX) was launched on April 28, 2003
and decommissioned by NASA on June 28, 2013. It imaged the sky in the
Ultraviolet (UV) for almost a decade.
The Galactic All-Sky Survey (GASS, J/ApJ/776/74) observations were
performed from January 2005 to November 2006, utilizing the 13-beam
21cm feed array installed at the Parkes 64m telescope in Australia.
The Effelsberg-Bonn HI Survey (EBHIS, J/A+A/585/A41) was conducted
with the Effelsberg 100m telescope in Germany, utilizing the 7-beam
21cm receiver. Measurements were carried out between end of 2008 and
early 2013.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 134 317 The main information of the dust clouds
table2.dat 57 58 Comparison of our cloud distances with
Magnani+ 1985ApJ...295..402M 1985ApJ...295..402M (MBM) molecular
cloud maps
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
VIII/7 : Hat Creek High-Latitude H I Survey (Heiles+ 1974-1976)
VII/244 : Atlas and Catalog of Dark Clouds (Dobashi+, 2005)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/156 : LAMOST DR7 catalogs (Luo+, 2019)
J/A+A/327/325 : Distances of molecular cloud (May+, 1997)
J/A+A/383/631 : Catalogue of dust clouds in the Galaxy (Dutra+, 2002)
J/ApJ/699/1153 : Kinematic dist. to GRS molecular clouds (Roman-Duval+, 2009)
J/ApJ/723/492 : Physical propert. GRS molecular clouds (Roman-Duval+, 2010)
J/PASJ/63/S1 : Atlas & cat. of dark clouds based on 2MASS (Dobashi+, 2011)
J/ApJ/786/29 : Catalog of distances to molecular clouds (Schlafly+, 2014)
J/A+A/585/A41 : EBHIS spectra and HI column density maps (Winkel+, 2016)
J/A+A/594/A116 : HI4PI spectra and column density maps (HI4PI team+, 2016)
J/ApJ/834/57 : Milky Way mol. clouds from 12CO (Miville-Deschenes+, 2017)
J/ApJ/861/153 : UV Extinction in the GALEX Bands. UVEXT (Sun+, 2018)
J/MNRAS/493/351 : A large catalogue of molecular clouds (Chen+, 2020)
J/A+A/654/A144 : 13CO (1-0) data molecular cloud cat. (Benedettini+, 2021)
J/MNRAS/506/150 : The GALAH+ Survey DR3 (Buder+, 2021)
J/ApJS/256/46 : Dist. & color excesses of high gal. mol. clouds (Sun+, 2021)
J/MNRAS/511/2302 : Molecular clouds study from 3D extinction maps (Guo+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Cloud Always "Cloud"
6 A1 --- m_Cloud [ab ] Component on Cloud (see "Level"=2)
7- 9 I3 --- ID [0/314] Internal cloud identifier
11- 16 F6.2 deg GLON [0.1/360] Galactic longitude (l)
18- 23 F6.2 deg GLAT [-88/85] Galactic latitude (b)
25- 28 F4.1 pc Rad [1.3/54.8]? Linear radius (r)
30- 33 I4 pc Dist0 [82/1349]? Distance (d0)
35- 37 I3 pc e_Dist0 [0/208]? Uncertainty in Dist0
39- 41 I3 pc deltad [0/161]? Thickness (δd)
43- 44 I2 pc e_deltad [0/65]? Uncertainty in deltad
46 I1 --- Level [1/4]? Distance level (1)
48- 51 F4.2 mag E0Gaia [0.01/0.51]? Cumulative Gaia blue-red
color excess (E0BP,RP)
53- 58 F6.4 mag e_E0Gaia [0/0.1]? Uncertainty in E0Gaia
60- 62 I3 pc hGaia [50/599]? Gaia blue and red scale height
(h'BP,RP)
64- 66 I3 pc e_hGaia [0/188]? Uncertainty in h'Gaia
68- 71 F4.2 mag delEGaia [0.02/0.9]? Gaia blue and red color
excess jump in the optical
(ΔEMCBP,RP)
73- 77 F5.3 mag e_delEGaia [0.001/0.13]? Uncertainty in delEGaia
79- 80 I2 --- m [2/16]? Cloud linear radius expansion
factor
82- 85 F4.2 mag E0NUV-BP [0.05/1.5]? Cumulative GALEX NUV-Gaia
blue color excess (E0NUV,BP)
87- 92 F6.4 mag e_E0NUV-BP [0.0015/0.52]? Uncertainty in E0NUV-BP
94- 96 I3 pc hNUV-BP [57/583]? GALEX NUV and Gaia blue scale
height (h'NUV,BP)
98-100 I3 pc e_hNUV-BP [4/193]? Uncertainty in h'NUV-BP
102-105 F4.2 mag delENUV-BP [0.04/1.81]? GALEX NUV and Gaia blue
color excess jump in the optical
(ΔEMCNUV,BP)
107-111 F5.3 mag e_delENUV-BP [0.015/1.03]? Uncertainty in delENUV-BP
113-117 I5 Msun Mass [38/29935]? Mass (M)
119-123 F5.1 Msun Sigma [1.8/173]? Surface mass density (Σ)
125-127 I3 --- GDR [64/996]? Gas-to-dust mass ratio
129-134 F6.2 --- CERs [-12.2/7.16]? Color excess ratio
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Note (1): To facilitate a more precise discourse on the cloud distance, the
clouds are divided into four levels according to the jump features, as
depicted in Figure 8. Level as follows:
1 = has exemplary jumps, wherein an ample number of foreground and cloud
sources provide discernible leaps
2 = presence of two discontinuities in the sight line, indicating the
existence of two clouds along that sight line. The two clouds in the
same sight line are labeled "a" (closer) and "b" (further).
3 = jumps of an uncertain nature, wherein an almost negligible number of
foreground stars precludes a definitive determination of the precise
location of the cloud jump, and thus only an upper limit on the
distance can be provided
4 = absence of clear jumps, where the extinction does not exhibit a
noticeable jump with distance
See Section 4.3.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- --- [Cloud]
7- 9 I3 --- ID [17/286] Internal cloud identifier as in Table 1
11- 13 A3 --- --- [MBM]
15- 17 I3 --- MBM [1/155] MBM cloud identifier (1)
19- 24 F6.2 deg GLON [0.4/345] Dust cloud galactic longitude
from this work
26- 31 F6.2 deg GLAT [-52/37] Dust cloud galactic latitude
from this work
33- 36 F4.2 deg angRad [0.5/2.4] Angular radius from this work
38- 43 F6.2 deg GLONM [0.9/345] MBM cloud galactic longitude (1)
45- 50 F6.2 deg GLATM [-52/37] MBM cloud galactic latitude (1)
52- 55 F4.2 deg angRadM [0.1/2.5]? MBM cloud angular radius (1)
57 I1 --- Flag [0/1]? Cloud position match flag (2)
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Note (1): Cloud number, Galactic coordinates and angular radius from MBM
(Magnani+ 1985ApJ...295..402M 1985ApJ...295..402M)
Note (2): Flag as follows:
0 = the main body of the MBM cloud is not within the cloud of this work
1 = the main body of the MBM cloud is within the cloud of this work
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History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 17-Jun-2025