J/ApJ/911/28 MW Project: DR2 "yellow balls" in Spitzer (Wolf-Chase+, 2021)
The Milky Way Project: probing star formation with first results on yellowballs
from DR2.
Wolf-Chase G., Kerton C.R., Devine K., Pouydal A., Mori J., Trujillo L.,
Cossairt A., Schoultz S., Jayasinghe T., Povich M.
<Astrophys. J., 911, 28 (2021)>
=2021ApJ...911...28W 2021ApJ...911...28W
ADC_Keywords: Star Forming Region; Surveys; Infrared; Radio sources
Keywords: Star formation ; Surveys ; Catalogs
Abstract:
Yellowballs (YBs) were first discovered during the Milky Way Project
(MWP) citizen science initiative. The MWP users noticed compact,
yellow regions in Spitzer Space Telescope mid-infrared (MIR) images of
the Milky Way plane and asked professional astronomers to explain
these "yellow balls." Follow-up work by Kerton+ (2015, J/ApJ/799/153)
determined that YBs likely trace compact photodissociation regions
associated with massive and intermediate-mass star formation. The YBs
were included as target objects in a version of the MWP launched in
2016, which produced a listing of over 6000 YB locations. We have
measured distances, cross-match associations, physical properties, and
MIR colors of ∼500 YBs within a pilot region covering the
l=30°-40°, b=±1° region of the Galactic plane. We find
that ∼20-30% of YBs in our pilot region contain high-mass star
formation capable of becoming expanding HII regions that produce MIR
bubbles. A majority of YBs represent intermediate-mass star-forming
regions whose placement in evolutionary diagrams suggest they are
still actively accreting and may be precursors to optically revealed
Herbig Ae/Be nebulae. Many of these intermediate-mass YBs were missed
by surveys of massive star formation tracers; thus, this catalog
provides information for many new sites of star formation.
Description:
The Milky Way Project (MWP) history, interface, images, workflow, and
identification tools, as well as the construction of the MWP DR2
bubble and bow shock catalogs, are presented in detail in
Jayasinghe+ 2019, J/MNRAS/488/1141
To help identify yellowballs (YBs) that are most likely associated
with regions of star formation, we cross-matched the 516 YBs in the
selected pilot region with catalogs of star-forming regions and
interstellar medium structures produced from surveys covering this
region. We used the Hi-GAL compact source catalog of
Elia+ (2017, J/MNRAS/471/100) containing 4764 sources within the pilot
region, the GaussClump Source Catalogue from ATLASGAL (624 sources;
Csengeri+ 2014, J/A+A/565/A75), the Co-Ordinated Radio "N" Infrared
Survey for High-mass star formation catalog (CORNISH, 494 sources;
Purcell+ 2013, J/ApJS/205/1), the RMS catalog (210 sources;
Lumsden+ 2013, J/ApJS/208/11), and the WISE Catalog of Galactic HII
Regions (672 sources; Anderson+ 2014, J/ApJS/212/1).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 91 6176 DR2 yellowballs (YBs)
table2.dat 146 516 YB DR2 pilot region cross-matches
table3.dat 46 516 YB position, velocity, and Bayesian distance
table4.dat 152 368 Physical properties of YB-Hi-GAL matched sources
table6.dat 53 516 Pilot region MIR photometry
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See also:
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
J/A+A/275/67 : Velocity Field of the outer Galaxy (Brand+ 1993)
J/A+A/481/345 : SED evolution in massive YSOs (Molinari+, 2008)
J/ApJ/720/679 : Optical spectroscopy in Cygnus X region (Beerer+, 2010)
J/A+A/537/A1 : Infrared fluxes of HII regions and PNe (Anderson+, 2012)
J/MNRAS/424/2442 : Catalog of bubbles from Milky Way Project (Simpson+, 2012)
J/A+A/544/A146 : ATLASGAL cold high-mass clumps with NH3 (Wienen+, 2012)
J/ApJS/208/11 : Red MSX Source Survey: massive protostars (Lumsden+, 2013)
J/ApJS/205/1 : CORNISH project. II. Source catalog (Purcell+, 2013)
J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)
J/A+A/565/A75 : ATLASGAL: dust condensations in Gal. plane (Csengeri+, 2014)
J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)
J/ApJ/799/153 : Yellowballs in Milky Way project (Kerton+, 2015)
J/MNRAS/471/100 : Hi-GAL compact source catalog. -71.0<l<67.0 (Elia+, 2017)
J/MNRAS/488/1141 : MW Project DR2 bubbles & bow shocks (Jayasinghe+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq [1/6176] Yellowball identifier
6- 18 F13.9 deg GLON [-0.042/360.01] Galactic longitude
20- 31 F12.9 deg GLAT [-2.23/3.59] Galactic latitude
33- 43 F11.9 deg Rad [0.001/0.05] Milky Way Project radius
45- 55 F11.9 deg e_GLON [1.6e-5/0.004]? Uncertainty in GLON
57- 67 F11.9 deg e_GLAT [2.3e-5/0.004]? Uncertainty in GLAT
69- 79 F11.9 deg e_Rad [3.3e-6/0.11]? Uncertainty in Rad
81- 91 F11.9 --- Rate [0.05/1] Hit rate (1)
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Note (1): The hit rate for a given cluster is the ratio of the total number of
classifications in the cluster to the total number of times images
containing the classified object were viewed by MWP users. See Section 2.
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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- 4 I4 --- Seq [1153/1670] Yellowball identifier
6- 16 F11.8 deg GLON [30/39.98] Galactic longitude
18- 29 F12.9 deg GLAT [-0.95/0.99] Galactic latitude
31- 37 A7 --- --- [HIGALBM]
38- 51 A14 --- HIGALBM Hi-Gal compact source catalog
(Elia+ 2017, J/MNRAS/471/100) ID (LL.llll+B.bbbb)
53- 68 A16 --- [CUS2014] ATLASGAL catalog (Csengeri+ 2014, J/A+A/565/A75)
identifier
70- 86 A17 --- CORNISH CORNISH catalog (Purcell+ 2013, J/ApJS/205/1)
identifier
88-102 A15 --- CType CORNISH type
104-107 I4 --- RMS [3090/4924]? Red MSX Source Survey catalog
(Lumsden+ 2013, J/ApJS/208/11) identifier
109-128 A20 --- RType RMS type
130-144 A15 --- WISE WISE HII region catalog
(Anderson+ 2014, J/ApJS/212/1) ID
(<[ABB2014] WISE GLLL.lll+BB.bbb> in Simbad)
146 A1 --- WType WISE type (1)
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Note (1): WISE type as follows:
K = Known (91 occurrences)
G = Group (18 occurrences)
C = Candidate (28 occurrences)
Q = radio quiet (126 occurrences)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq [1153/1669] Yellowball identifier
6- 16 F11.8 deg GLON [30/39.94] Galactic longitude
18- 29 F12.9 deg GLAT [-1.04/0.99] Galactic latitude
31- 35 F5.1 km/s Vel [0.5/116.4]? Velocity (2)
37- 41 F5.2 kpc Dist [0.24/13.5]? Bayesian distance (3)
43- 46 F4.2 kpc e_Dist [0.02/2.2]? Uncertainty in Dist
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Note (2): Yellowballs (YBs) with no 13CO association (n=23) indicated by
blanks.
Note (3): Bayesian distance calculator output using Pfar=0.5.
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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- 4 I4 --- Seq [1153/1669] Yellowball identifier
6- 12 F7.4 deg GLON [30/39.94] Galactic longitude
14- 20 F7.4 deg GLAT [-0.9/0.99] Galactic latitude
22- 26 F5.2 kpc Dist [0.54/15.37] Distance
28- 31 F4.2 kpc e_Dist [0.07/2.2] Uncertainty in Dist
33- 38 F6.3 kpc HDist [0/14.5] HIGAL distance
40- 40 A1 --- f_HDist Flag on HDist (1)
42- 49 F8.2 Msun Mass [1.19/15700] Rescaled mass
51- 57 F7.2 Msun e_Mass [0.3/2443] Uncertainty in Mass
59- 68 F10.2 Lsun Lum [3.3/1115293] Rescaled bolometric luminosity
70- 77 F8.2 Lsun e_Lum [2.4/51396] Uncertainty in Lum
79- 82 F4.2 pc Diam [0.05/2.2] Rescaled diameter
84- 88 F5.3 pc e_Diam [0.002/0.22] Uncertainty in Diam
90- 95 F6.2 --- Ratio [0.1/232] Ratio of Lum to Mass
97-102 F6.2 --- e_Ratio [0.02/198] Uncertainty in Ratio
104-108 F5.2 K Tgray [8.88/40] Dust temperature from greybody fit
110-113 F4.2 K e_Tgray [0.12/3.6] Uncertainty in Tgray
115-120 F6.2 --- Lratio [6/557] Ratio of Lum to luminosity >350um
122-127 F6.2 --- e_Lratio [1/112] Uncertainty in Lratio
129-134 F6.2 K TBol [18/128] Bolometric temperature (2)
136-140 F5.2 K e_TBol [3.6/26] Uncertainty in TBol
142-146 F5.3 g/cm2 SDen [0.005/6.9] Surface density
148-152 F5.3 g/cm2 e_SDen [0.001/2.7] Uncertainty in SDen
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Note (1): Indicates the quality of the solution to the near/far distance
ambiguity.
G = Ambiguity was solved by matching the source position with a catalog of
sources with known distances (e.g., H II regions, masers, etc.) or
with features in extinction maps.
B = No source position or features in extinction maps.
N = A distance estimate was unavailable.
Note (2): Calculated using equation (5) in Elia et al. (2017MNRAS.417..100E 2017MNRAS.417..100E).
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq [1153/1670] Yellowball identifier
6- 10 F5.2 Jy F8 [0.02/16.67]? Mean 8 micron flux density
12- 16 F5.2 --- stdF8 [0/69]? Normalized standard deviation in F8 (4)
18- 21 F4.2 Jy F12 [0/7.7]? Mean 12 micron flux density
23- 26 F4.2 --- stdF12 [0.01/8]? Normalized standard deviation
in F12 (4)
28- 32 F5.2 Jy F24 [-0.01/13.1]? Mean 24 micron flux density
34- 37 F4.2 --- stdF24 [0.01/2.5]? Normalized standard deviation
in F24 (4)
39- 45 F7.2 Jy F70 [0.9/2563]? Hi-GAL 70 micron flux density
from Elia et al. (2017MNRAS.417..100E 2017MNRAS.417..100E)
47- 51 F5.2 Jy e_F70 [0.05/90]? Uncertainty in F70
53- 53 I1 --- Fit [1]? Well-fit by 2D Gaussian model flag? 1=Yes
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Note (4): Fractional error (standard deviation divided by mean) of the
photometric measurement. See text for details.
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History:
From electronic version of the journal
References:
Jayasinghe et al. MWP DR2. 2019MNRAS.488.1141J 2019MNRAS.488.1141J Cat. J/MNRAS/488/1141
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Oct-2022