J/MNRAS/469/1545 New compact star cluster candidates in GP (Froebrich, 2017)
New compact star cluster candidates in the Galactic plane.
Froebrich D.
<Mon. Not. R. Astron. Soc., 469, 1545-1552 (2017)>
=2017MNRAS.469.1545F 2017MNRAS.469.1545F (SIMBAD/NED BibCode)
ADC_Keywords: Galactic plane ; Associations, stellar
Keywords: Galaxy: evolution - Galaxy: general -
open clusters and associations: general - Galaxy: structure -
galaxies: star clusters: general
Abstract:
The sample of known star clusters, the fundamental building blocks of
galaxies, in the Milky Way is still extremely incomplete for objects
beyond a distance of 1-2kpc. Many of the more distant and young
clusters are compact and hidden behind large amounts of extinction. We
thus utilized the deep high-resolution near-infrared surveys UGPS and
VVV to uncover so far unknown compact clusters and to analyse their
properties. Images of all objects in the area covered by these two
surveys, which are listed as galaxy in SIMBAD, have been inspected and
125 so far unknown stellar clusters and candidate clusters have been
identified. Based on the frequent associations with star formation
indicators (nebulosities, IRAS sources, HII regions, masers) we find
that the typical cluster in our sample is young, at distances between
1-10 kpc and has a typical apparent radius of 25-arcsec. We suggest
more systematic searches, e.g. at all positions of 2MASS extended
sources to increase the completeness of the known cluster sample
beyond distances of 2kpc.
Description:
In order to identify potentially undetected star cluster (candidates)
in the Galactic plane, we manually inspected images from the UGPS and
VVV surveys for all objects classified as 'Galaxy' in SIMBAD to
identify misclassified star clusters. A total of 4387 objects were
initially selected and JHK images for 3409 of those were available and
investigated in detail in an area of 2350 deg2 over both surveys.
In total, we have identified 77 new clusters, 53 of which are not
included in the list of Lucas et al. (in preparation). All the
determined properties are listed in Table A1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 110 119 Properties of all clusters and candidates that
are not included in the list of
Lucas et al. (in prep.)
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Sample Sample code (1)
5- 10 A6 --- Name Name, Cl NNN
12- 13 I2 h RAh Rihgt ascension (J2000)
15- 16 I2 min RAm Rihgt ascension (J2000)
18- 21 F4.1 s RAs Rihgt ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 31 I2 arcsec DEs Declination (J2000)
33- 42 F10.6 deg GLON Galactic longitude
44- 52 F9.6 deg GLAT Galactic latitude
54- 68 A15 --- IRAS IRAS cross-identification, IRAS HHMMm+DDMM
70- 87 A18 --- MSX MSX cross-identification, (GLLL.llll+BB.bbbb)
89- 91 A3 --- HII Associated with HII ? (2)
93 A1 --- Maser Associated with maser ? (2)
95 A1 ---- Neb Associated with nebula ? (2)
97-101 F5.2 kpc Dist ? Distance, obtained from associated RMS sources
103-104 I2 arcsec Rad ? Apparent radius
106-107 I2 --- NMan ? Number of potential members determined
manually from the images
109-110 I2 --- Naut ? Number of potential members determined
automatically from the photometric catalogues
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Note (1): Sample as follows:
N = New clusters
NC = New Cluster Candidates
CC = Confirmed Cluster Candidates
UC = Unconfirmed Cluster Candidates
UO = Unclassified Candidate Object
Note (2): associations with known HII regions, masers and nebulosities
(identified in the JHK images).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 02-Apr-2020