J/ApJS/248/3 A 4-6GHz RRL survey in the Milky Way (Chen+, 2020)
A 4-6 GHz radio recombination line survey in the Milky Way.
Chen H.-Y., Chen Xi, Wang J.-Z., Shen Z.-Q., Yang K.
<Astrophys. J. Suppl. Ser., 248, 3 (2020)>
=2020ApJS..248....3C 2020ApJS..248....3C
ADC_Keywords: Radio lines; Masers; Milky Way; Star Forming Region;
Infrared sources; H II regions
Keywords: Star formation ; Star-forming regions ; Interstellar line emission ;
Interstellar abundances ; Interstellar atomic gas ;
Dense interstellar clouds ; Interstellar line absorption ;
H II regions ; Compact H II region
Abstract:
We performed a radio recombination line (RRL) survey to construct a
high-mass star-forming region (HMSFR) sample in the Milky Way based on
the all-sky Wide-Field Infrared Survey Explorer point-source catalog.
The survey was observed with the Shanghai 65m Tianma radio telescope
covering 10 hydrogen RRL transitions ranging from H98α to
H113α (corresponding to the rest frequencies of 4.5-6.9GHz)
simultaneously. Out of 3348 selected targets, we identified an HMSFR
sample consisting of 517 sources traced by RRLs; a large fraction of
this sample (486) is located near the Galactic Plane (|b|<2°). In
addition to the hydrogen RRLs, we also detected helium and carbon RRLs
toward 49 and 23 sources, respectively. We crossmatch the RRL
detections with the 6.7 methanol maser sources built up in previous
works for the same target sample. As a result, 103 HMSFR sources were
found to harbor both emissions. In this paper, we present the HMSFR
catalog accompanied by the measured RRL line properties and a
correlation with our methanol maser sample, which is believed to trace
massive stars at earlier stages. The construction of an HMSFR sample
consisting of sources in various evolutionary stages indicated by
different tracers is fundamental for future studies of high-mass star
formation in such regions.
Description:
The observations were performed between 2015 September and 2018
January with the 65m Tianma radio telescope (TMRT) in Shanghai, China.
Radio recombination lines (RRLs) and 6.7GHz methanol masers were
observed simultaneously in our survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 165 669 Characteristics of the hydrogen radio
recombination line (RRL) emission sample
(517 unique IDs)
table4.dat 23 654 List of high-mass star-forming region (HMSFR)
sources traced by RRL and/or methanol maser
table5.dat 147 72 Characteristics of helium and carbon RRL emissions
table6.dat 151 5 Characteristics of the PNe candidates
table7.dat 161 9 Characteristics of the SNR candidates
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See also:
VII/20 : Catalogue of HII Regions (Sharpless 1959)
VII/216 : H-α emission regions in Southern Milky Way (Rodgers+ 1960)
VIII/58 : A Survey of Radio H II Regions in the Northern Sky (Lockman+ 1989)
V/112 : Catalog of Star-Forming Regions in the Galaxy (Avedisova, 2002)
VIII/96 : 6-GHz methanol multibeam maser catalogue (Caswell+, 2010-12)
II/328 : AllWISE Data Release (Cutri+ 2013)
J/A+A/171/261 : RRLs of Southern HII Regions (Caswell+ 1987)
J/MNRAS/301/640 : Ultracompact H II regions studies. II. (Walsh+, 1998)
J/A+A/403/1095 : 6.7GHz methanol masers survey of YSOs (Minier+, 2003)
J/ApJ/653/1226 : Physical properties of galactic HII regions (Quireza+, 2006)
J/A+A/472/835 : JHKs and GLIMPSE photometry of RCW 120 (Zavagno+, 2007)
J/other/PASA/26.454 : Precise positions of methanol masers (Caswell, 2009)
J/ApJ/690/706 : Distances of Galactic HII regions (Anderson+, 2009)
J/ApJS/194/32 : HII Region Discovery Survey (HRDS). II. (Anderson+, 2011)
J/ApJ/738/27 : Galactic HII regions RRL and continuum data (Balser+, 2011)
J/AZh/89/611 : Class I methanol maser catalog (Bayandina+, 2012)
J/AN/333/634 : Torun methanol source catalogue (Szymczak+, 2012)
J/ApJ/764/34 : HRDS IV. H, He & C radio recombination lines (Wenger+, 2013)
J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)
J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)
J/MNRAS/443/1555 : ATLASGAL massive star forming clumps (Urquhart+, 2014)
J/MNRAS/450/2025 : HIPASS-ZoA HII regions (Alves+, 2015)
J/ApJ/806/199 : RRL & continuum data of 21 Gal. HII regions (Balser+, 2015)
J/ApJ/833/18 : Ultra-compact HII regions & methanol masers. I. (Hu+, 2016)
J/ApJS/227/25 : 6 & 1.3cm deep VLA obs. toward 58 HMSFRs (Rosero+, 2016)
J/AJ/152/92 : Ammonia & CO outflow around methanol masers (Li+, 2016)
J/ApJ/846/160 : 6.7GHz Class II methanol maser survey (Yang+, 2017)
J/other/RAA/18.146 : Spiral structure of the Milky Way (Xu+, 2018)
J/ApJS/240/14 : SIGGMA: inner galaxy data release (Liu+, 2019)
J/ApJS/245/12 : 6.7GHz methanol masers & RRLs in MSX regions (Ouyang+, 2019)
J/ApJS/241/18 : A 6.7GHz methanol maser survey. II. |b|<2° (Yang+, 2019)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- ID Identifier (GLLL.lll+BB.bbb)
17- 18 I2 h RAh Hour of Right Ascension (J2000) (G1)
20- 21 I2 min RAm Minute of Right Ascension (J2000) (G1)
23- 27 F5.2 s RAs Second of Right Ascension (J2000) (G1)
29 A1 --- DE- Sign of the Declination (J2000) (G1)
30- 31 I2 deg DEd Degree of Declination (J2000) (G1)
33- 34 I2 arcmin DEm Arcminute of Declination (J2000) (G1)
36- 39 F4.1 arcsec DEs Arcsecond of Declination (J2000) (G1)
41- 50 A10 "D/M/Y" Epoch Observation epoch
52- 55 I4 mK Tb [4/1918] Measured peak antenna tempature (G2)
57- 61 F5.2 K.km/s Si [0.1/58.2]? Integral flux (G2)
63- 66 F4.2 K.km/s e_Si [0.01/0.4]? Uncertainty in Si
68- 71 F4.1 km/s DeltaV [4.8/91]? FWHM (ΔV) (G2)
73- 76 F4.1 km/s e_DeltaV [0.1/11]? Uncertainty in DeltaV
78- 82 F5.1 km/s nup [-73/157]? Radio defined LSR velocity at peak
(νp)
84- 86 F3.1 km/s e_nup [0/5]? Uncertainty in nup
88- 92 F5.2 kpc Dist [0.42/15.7]? Bayesian distance (d) (G3)
94- 97 F4.2 kpc e_Dist [0.01/1.7]? Uncertainty in Dist (G3)
99-117 A19 --- Notes Complementary information (1)
119-121 A3 --- Maser Association with 6.7GHz methanol maser
123-165 A43 --- Other Other identifiers (G4)
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Note (1):
SL = side-lobe detected source;
? = weak source without accurate Gaussian line fitting.
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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 --- Fig [1/517]? Figure number in Appendix A1;
column added by CDS
5- 5 A1 --- f_ID Source code (1)
7- 21 A15 --- ID Identifier (GLLL.lll+BB.bbb)
23 A1 --- m_ID Right/left hand side of the components (2)
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Note (1): Code as follows:
a = RRL-only sources (414 occurrences);
b = Sources associated with both RRL and methanol maser (103 occurrences);
c = Methanol-maser-only sources (137 occurrences).
Note (2): For sources showing multiple methanol emissions, "R" and "L" label
the right/left hand side of the components (see
Yang+ 2017, J/ApJ/846/160 and 2019, J/ApJS/241/18).
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Byte-by-byte Description of file: table[567].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- ID Identifier (GLLL.lll+BB.bbb)
17- 18 I2 h RAh Hour of Right Ascension (J2000) (G1)
20- 21 I2 min RAm Minute of Right Ascension (J2000) (G1)
23- 27 F5.2 s RAs Second of Right Ascension (J2000) (G1)
29 A1 --- DE- Sign of the Declination (J2000) (G1)
30- 31 I2 deg DEd Degree of Declination (J2000) (G1)
33- 34 I2 arcmin DEm Arcminute of Declination (J2000) (G1)
36- 39 F4.1 arcsec DEs Arcsecond of Declination (J2000) (G1)
41- 50 A10 "D/M/Y" Epoch Observation epoch
52- 54 I3 mK Tb [7/252] Measured peak antenna tempature (G2)
56- 59 F4.2 K.km/s Si [0.06/3.8]? Integral flux (G2)
61- 64 F4.2 K.km/s e_Si [0.01/0.4]? Uncertainty in Si
66- 69 F4.1 km/s DeltaV [2.2/70.2]? FWHM (ΔV) (G2)
71- 73 F3.1 km/s e_DeltaV [0.1/7]? Uncertainty in DeltaV
75- 80 F6.1 km/s nup [-190/118]? Radio defined LSR velocity at peak
(ν_p)
82- 84 F3.1 km/s e_nup [0/3.3]? Uncertainty in nup
86- 90 F5.2 kpc Dist [0.5/13]? Bayesian distance (d) (G3)
92- 95 F4.2 kpc e_Dist [0.01/1.5]? Uncertainty in Dist (G3)
97- 98 A2 --- Type Emission type (1)
100-102 A3 --- Maser Association with 6.7 GHz methanol maser
104-107 A4 --- OT Object type (only for Tables 6 and 7)
109-161 A53 --- Other Other identifiers (G4)
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Note (1): "He" and "C" label the He and C RRLs respectively.
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Global notes:
Note (G1): Of the pointing center.
Note (G2): Of the Gaussian fitting.
Note (G3): Calculated following Reid+ (2016ApJ...823...77R 2016ApJ...823...77R) with
a default equal weighting (Pfar=0.5) on near and far distance
probability.
Note (G4): For sources associated with an Anderson2014 source, we label the
type of the Anderson (2014, J/ApJS/212/1) counterpart:
"K" for "Known" sources, "C" for "candidate" sources,
"G" for "Grouped" sources and "Q" for "Radio quiet" sources.
For multi-component sources, the components are sorted by peak
line intensity.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Jul-2020