J/MNRAS/487/1057 Massive SFR beyond the solar circle (Djordjevic+, 2019)
Beyond the solar circle - trends in massive star formation between the
inner and outer galaxy.
Djordjevic J.O., Thompson M.A., Uruqhart J.S., Forbrich J.
<Mon. Not. R. Astron. Soc. 487, 1057 (2019)>
=2019MNRAS.487.1057D 2019MNRAS.487.1057D (SIMBAD/NED BibCode)
ADC_Keywords: H II regions ; Millimetric/submm sources
Keywords: catalogues - surveys - star formation - H II regions -
radio continuum: ISM - submillimetre: ISM
Abstract:
We have compiled the most complete compact and ultracompact HII region
catalogue to date via multi-wavelength inspection of survey data. We
utilise data from the recently available SASSy 850um survey to
identify massive star forming clumps in the outer Galaxy
(RGC>8.5kpc) and cross-match with infrared and radio data of known
UC HII regions from the RMS database. For the inner Galaxy sample
(RGC<8.5kpc), we adopt the compact HII regions from previous works
that used similar methods to cross match ATLASGAL with either CORNISH
or RMS, depending on the location within the Galactic plane. We
present a new UC HII region catalogue that more than doubles the
original sample size of previous work, totalling 536 embedded HII
regions and 445 host clumps. We examine the distance independent
values of NLy/M and Lbol/M as proxies for massive star formation
efficiency and overall star formation efficiency, respectively. We
find a significant trend showing that Lbol/M decreases with
increasing RGC, suggesting that the overall star formation per unit
mass is less in the outer Galaxy.
Description:
Our goal in this paper is to use the Urquhart et al. (2013, Cat.
J/MNRAS/435/400) sample of HII regions as a starting point to build
the rest of a catalogue that will be well-sampled, reliable, and
complete for a significant range of RGC.
Table 1. Derived clump properties of the host molecular clumps. The
first column gives Submillimetre Name (AGAL for ATLASGAL objects;
JCMTLSY for SASSy) with superscripts denoting publication clump source
was adopted from: 1) Urquhart et al. (2013, Cat. J/MNRAS/435/400);
2) Urquhart et al. (2014, Cat. J/MNRAS/443/1555); 3) Thompson et. al.
in prep. The remaining columns include: Complex that clump belongs to
(if any); HIIRegion Density; Radial Velocity; Heliocentric Distance;
Galactocentric Radius; Flag denoting source of adopted distance
information([1] Urquhart et al. (2018, Cat. J/MNRAS/473/1059);
[2] Urquhart et al. (2013, Cat. J/MNRAS/435/400); [3] Urquhart et al.
(2014, Cat. J/MNRAS/443/1555); [4] Adopted from RMS database,
http://rms.leeds.ac.uk/cgi-bin/public/RMS_DATABASE.cgi); Effective
Radius of clump; Peak and Integrated submillimetre fluxes; Gas-to-dust
Ratio Value with Giannetti et al. (2015A&A...580L...7G 2015A&A...580L...7G) correction;
Column Density; Corrected Column Density; Clump Mass; Corrected Clump
Mass.
Table 2. Derived HIIregion properties for a selection of the full
sample. Columns are as follows - Radio Name (in galactic
coordinates);Submillimetre Name (as previously defined); Offset
between radio and submillimetre centres; Radio Peak and Integrated
fluxes; Angular Diameter; Physical Diameter; Frequency of observations;
Lyman continuum flux; Bolometric Luminosity; Associated Ratios as
discussed in Section 6.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 114 445 Derived clump properties of the host
molecular clumps
table2.dat 120 536 Derived HII region properties for a selection
of the full sample
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See also:
J/MNRAS/435/400 : ATLASGAL. Properties of compact HII regions (Urquhart+ 2013)
J/MNRAS/443/1555 : ATLASGAL massive star forming clumps sample (Urquhart+ 2014)
J/MNRAS/473/1059 : Galactic clump properties complete sample (Urquhart+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 27 A27 --- Submm Submillimetre name (AGAL for ATLASGAL objects;
JCMTLSY for SASSy)`
29 I1 --- r_Submm [1/3] Reference for Submm name (1)
31- 41 A11 --- Complex ? Complex that clump belongs to (if any)
43- 44 I2 --- HII [1/13]? HII Region Density
46- 51 F6.1 km/s vlsr ? LSR radial velocity
53- 57 F5.2 kpc D ? Heliocentric distance
59- 63 F5.2 kpc Rgal ? Galactocentric distance
65 I1 --- r_D [1/4]? Reference for D (2)
67- 71 F5.2 pc Radius ? Effective Radius of clump
73- 77 F5.2 Jy/beam FsubmmP Peak submillimetre flux
79- 85 F7.2 Jy FsubmmInt Integrated submillimetre flux
87- 92 F6.2 --- Rc ? Gas-to-dust ratio value with Giannetti et
al. (2015A&A...580L...7G 2015A&A...580L...7G) correction
94- 98 F5.2 [cm-2] LogNH2 Column density
100-104 F5.2 [cm-2] LogNH2c ? Corrected column density
106-109 F4.2 [Msun] LogMcl ? Clump mass
111-114 F4.2 [Msun] LogMclc ? Corrected clump mass
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Note (1): Submillimetre name references as follows:
1 = Urquhart et al. (2013, Cat. J/MNRAS/435/400)
2 = Urquhart et al. (2014, Cat. J/MNRAS/443/1555)
3 = Thompson et. al., in prep.
Note (2): Distance references as follows:
1 = Urquhart et al. (2018, Cat. J/MNRAS/473/1059)
2 = Urquhart et al. (2013, Cat. J/MNRAS/435/400)
3 = Urquhart et al. (2014, Cat. J/MNRAS/443/1555)
4 = Adopted from RMS database,
http://rms.leeds.ac.uk/cgi-bin/public/RMS_DATABASE.cgi
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Radio Radio name (in galactic coordinates)
20 I1 --- r_Radio [1/3] Reference for Radio name (1)
22- 48 A27 --- Submm Submillimetre name
50- 55 F6.2 arcsec Offset ? Offset between radio and submillimetre
centres
57- 62 F6.2 mJy/beam FRadioP ? Radio peak flux
64- 71 F8.2 mJy FradioInt ? Integrated flux
73- 77 F5.2 arcsec Diam ? Angular diameter
79- 82 F4.2 pc Diampc ? Physical diameter
84- 86 F3.1 GHz Freq ? Frequency of observations
88- 92 F5.2 ph/s LogNly ? Lyman continuum flux
94- 97 F4.2 [Lsun] LogLbol ? Bolometric luminosity
99-102 F4.2 [Lsun/Msun] LogLbol/M ? Bolomatric luminosity to mass ratio
104-108 F5.2 [Lsun/Msun] LogLbol/Mc ? Corrected bolometric luminosity to mass
ratio
110-114 F5.2 [ph/s/Msun] LogNly/M ? Lyman continuum to mass ratio
116-120 F5.2 [ph/s/Msun] LogNly/Mc ? Corrected Lyman continuum to mass ratio
--------------------------------------------------------------------------------
Note (1): Reference for Radio name as follows:
1 = CORNISH and ATLASGAL matching
2 = RMS and ATLASGAL matching
3 = RMS and SASSy matching
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Acknowledgements:
J.O. Djordjevic, j.djordjevic(at)herts.ac.uk
(End) Patricia Vannier [CDS] 18-May-2019