J/A+A/568/A51 Milky Way global survey of star clusters. III. (Schmeja+, 2014)
Global survey of star clusters in the Milky Way.
III. 139 new open clusters at high Galactic latitudes.
Schmeja S., Kharchenko N.V., Piskunov A.E., Roeser S., Schilbach E.,
Froebrich D., Scholz R.-D.
<Astron. Astrophys. 568, A51 (2014)>
=2014A&A...568A..51S 2014A&A...568A..51S
ADC_Keywords: Clusters, open ; Proper motions ; Milky Way
Keywords: techniques: photometric - catalogs - astrometry - stars: kinematics -
open clusters and associations: general - Galaxy: stellar content
Abstract:
We present a list of 139 new open clusters at high Galactic latitudes
(|b|>18.5°) that are found in the frame of the project Milky Way
Star Clusters (MWSC). The target list was compiled as density
enhancements using the 2MASS catalogue. For confirmed clusters we
determined a homogeneous set of astrophysical parameters such as
membership, angular radii of the main morphological parts, proper
motion, distance, reddening, age, tidal parameters.
Description:
We were looking for stellar density enhancements using a star count
algorithm in the 2MASS point source catalogue (II/246). In total we
discovered 714 density enhancements (regarded as cluster candidates).
The candidates were cross-identified with known objects. Unidentified
objects were passed through the standard MWSC pipeline for
verification, cluster membership construction and structure, kinematic
and astrophysical parameter determination. The basic stellar data were
taken from the all-sky catalogue 2MAst (2MASS with Astrometry), that
was extracted from the all-sky catalogues PPMXL (Roeser et al. 2010,
Cat. I/317) and 2MASS (Cutri et al. 2003, Cat. II/246). We found
that 359 candidates coincide with known objects, other 355 candidates
are non identified, and 139 of them we classified as real star
clusters and determined their basic cluster parameters.
Around each confirmed object from our target list we defined a
circular area with a radius of ra=r2+radd where r2 is initial
estimate of cluster radius, and radd=0.3°. In these areas we
selected in 2MAst only those stars with flags Rflg (the 2nd triple of
the flags in 2MASS) set to 1, 2, or 3 in each band, i.e. the stars
with the best quality detections in photometric and astrometric data.
The 139 sky areas with confirmed clusters contain about 0.52 mln 2MAst
stars with best quality detections in photometric and astrometric
data. We selected most probable members and determined - with a
homogeneous method/pipeline - angular sizes of the main morphological
parts, heliocentric distances, colour-excesses, mean proper motions,
ages, tidal parameters.
This work extends MWSC project having input list of 3784 targets by
714 new candidates. We have adopted for them that MWSC numbering
starts with 5001. Since the search was performed for Northern and
Southern hemispheres separately the candidate numbering is
discontinuous: the numbers 5001≤MWSC<5499 are assigned at b>18.5,
and 5500≤MWSC<5999 designate candidates at b←18.5.
We present:
The Catalogue of new MWSC open clusters found at high galactic
latitudes (|b|>18.5°) which includes several files:
Catalogue of cluster parameters (confirmed clusters only);
Index of all MWSC(|b|>18.5 deg) candidates;
Notes for every item of index list.
Within each list the entries are ordered along with MWSC number.
The Catalogues of the MWSC Stars in 139 circular sky areas with
confirmed clusters. Files are ordered by MWSC number; inside each sky
area the entries are ordered by Ks magnitudes.
The Atlas of new MWSC clusters diagrams.
In the Atlas the Cluster pages are ordered by MWSC number.
All the data are given in the same format as in the main MWSC catalogue
(Cat. J/A+A/558/A53).
Description of file: atlas/*
For each cluster we prepared two EPS-pages of diagrams:
* Page 1 contains the cluster map as the basic panel
(file MWSCNamemap.eps.gz),
* Page 2 contains the Ks,(J-Ks) and Ks,(J-H) CMDs as basic panels
(file MWSCNamecmd.eps.gz).
The legend on each page gives the cluster name, MWSC number, (COCD
number); equatorial RAJ2000, DecJ2000, and galactic l, b coordinates
of the cluster centre; apparent cluster sizes r0, r1, r2, [number of
1sigma-members within the corresponding radius]; weighted average
components PM_(X,Y) of proper motion with their rms errors, [number of
stars used to compute the average]; the average radial velocity, RV
with their rms error, [the number of stars used to compute the
average]; distance to the cluster, d, distance modulus, (Ks-M_Ks);
NIR colour-excesses, E(J-H), E(J-Ks), interstellar extinction, A(Ks);
cluster age, its rms error, [the number of stars used to compute the
average age, or it is -1 if a manual isochrone fit was applied].
Additionally we show in the 2nd pages: an empirical correction
Delta_H for a better isochrone fit in the K_s,(J-H) diagram.
Symbols and their colours have the same meaning in all plots. Stars
are shown as coloured circles or dots. Cyan symbols mark stars outside
the cluster radius r2, green symbols are stars within r2. The most
probable kinematic and photometric members (1sigma-members) are
indicated in black, red, or blue. Black is for members located within
r1 (a visible radius of the central part), red for members between r1
and r2, and blue for stars outside r2 (the probabilities are formal).
Cyan bars show the uncertainty for 1sigma-members.
Description of files MWSCNamemap.eps.gz (Page 1):
Page 1 contains five diagrams with spatial information.
The right panel is a map of the cluster neighborhood (MAP),
the left panels show (upside-down) relations depending on the distance from
the cluster centre, r, for:
-magnitude Ks (Ks vs. r),
-proper motions (PM vs. r),
-density profile diagram (DPD).
MAP:
Stars are displayed as small circles.
The circle size corresponds to the stellar magnitude ranged in six
Ks mag intervals:
< 6.0, 6.0 - 8.0, 8.0 - 10.0, 10.0 - 12.0, 12.0 - 14.0, > 14.0.
Blue cross : cluster centre selected in this study;
Blue plus : cluster centre from the literature;
Magenta plusses : centres of other clusters (from target list) visible
(if any) in the map;
Dotted blue large circle : cluster core border (r0);
Solid blue large circle : inner cluster border (r1);
Dashed blue large circle : cluster corona border (r2).
The left panels:
Blue vertical dotted, solid, dashed lines mark r0, r1, r2, respectively.
PM vs. r: Magenta horizontal lines correspond to the average proper
motion of the cluster determined in this paper;
DPD: Density profiles (Log of Number of stars per 1 sq.deg) are shown for
all stars (green line), 3sigma-members (blue line), 2sigma-members (magenta
line) and 1sigma-members (black line).
Description of files MWSCNamecmd.eps.gz (Page 2):
Page 2 contains diagrams with kinematic and photometric information.
The three left panels are:
-two PM_(X,Y) vs. Ks relations, i.e. PM-magnitude equation diagrams (MEDs);
-the vector point diagram of proper motions (VPD).
The two upper right panels are:
-relations (Ks,(J-H) and Ks,(J-Ks), i.e. the colour-magnitude diagrams
(CMDs).
The bottom right panels:
-colour-colour diagrams (CCDs);
-reddening-independent parameter Q-colour diagrams (QCDs).
The CCDs and QCDs are separated into two subpanels (as well as CMDs and MEDs
are separated into two parts via a broken line). The division is made with
respect to the Ks_mc magnitude: in the bottom subpanels we place data for Ks
> Ks_mc, in the upper ones - for Ks < Ks_mc, where Ks_mc is Ks-magnitude at
the bluest colour (J-Ks) of the isochrone closest to the determined cluster
age.
CMDs:
Magenta curve: the apparent isochrone closest to the determined cluster age;
Solid blue lines: left and right borders of a domain of 100% photometric
cluster members;
Solid red lines: ZAMS and TAMS (shown only in the Ks,(J-Ks) diagram), the
borders of the evolved Main Sequence stars;
Magenta dashed line: corresponds to the Ks_mc;
Thick yellow circles: stars selected for age determination;
Black arrows: increasing interstellar extinction vectors.
MED:
Magenta solid lines correspond to the average proper motion of the
cluster; the magenta dashed line corresponds to the Ks_mc.
CCD and QCD:
The Magenta curve corresponds to the apparent isochrone (observed magnitudes
and colours); the cyan curve corresponds to the intrinsic isochrone.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
catalog.dat 280 139 Catalog of parameters for new open clusters
index.dat 45 782 List of MWSC new candidates
notes.dat 196 782 Notes to MWSC new candidates
stars/* . 139 *Star catalogs for 139 sky areas
atlas/* . 278 *Two EPS pages with diagrams for each cluster
--------------------------------------------------------------------------------
Note on stars/* :
The file names include the MWSC(|b|>18.5 deg) sequential number + 5000 and a
name of a cluster, preceded by a prefix "2m_" e.g. "2m5004MWSC_5004.dat" for
the cluster MWSC_5004.
Note on atlas/* :
The file names include the MWSC(|b|>18.5 deg) sequential number + 5000 and a
name of a cluster, e.g. "5004MWSC5004_map.eps.gz" for the 1st page with a map
as a basic panel, and "5004MWSC5004_cmd.eps.gz" for the 2nd page with CMDs as
basic panels.
--------------------------------------------------------------------------------
See also:
I/280 : ASCC catalog of 2.5 million stars (Kharchenko+ 2009)
I/317 : The PPMXL Catalog (Roeser+ 2010)
V/132 : SAI Open Clusters Catalog (Glushkova+, 2009)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VII/202 : Globular Clusters in the Milky Way (Harris, 1997)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/A+A/438/1163 : Catalogue of Open Cluster Data (COCD) (Kharchenko+, 2005)
J/A+A/440/403 : 109 new Galactic open clusters (Kharchenko+, 2005)
J/ApJ/635/560 : Star clusters discovered in GLIMPSE survey (Mercer+ 2005)
J/MNRAS/374/399 : Infrared star clusters with |b|<20° (Froebrich+, 2007)
J/MNRAS/409/1281 : Old star clusters in the FSR catalogue (Froebrich+, 2010)
J/A+A/558/A53 : MWSC II. The catalog of basic parameters (Kharchenko+ 2013)
J/A+A/543/A156 : MWSC. Paper I. (Kharchenko+, 2012)
Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I04 --- MWSC [5004/5963] MWSC number
6- 22 A17 --- Name NGC, IC or other common designation
24- 24 A1 --- Type [r] Cluster type (r=remnant)
25- 25 A1 --- n_Type [oc] object/candidate
26- 34 F9.4 h RAhour Adopted cluster centre in RA J2000.0
35- 42 F8.3 deg DEdeg Adopted cluster centre in Dec J2000.0
43- 50 F8.3 deg GLON Galactic longitude
51- 58 F8.3 deg GLAT Galactic latitude
59- 65 F7.3 deg r0 ?=0.000 Angular radius of the core
66- 72 F7.3 deg r1 Angular radius of the central part
73- 79 F7.3 deg r2 [0.09/0.3] Angular radius of the cluster
80- 86 F7.2 mas/yr pmRA [-13.1/8.4] Average proper motion in RA*cos(DE)
87- 93 F7.2 mas/yr pmDE [-11.6/10.2] Average proper motion in DE
94-100 F7.2 mas/yr e_pm [0.4/4.7] Error of pm
101-108 F8.2 km/s RV [999.99] Average radial velocity (not used)
109-116 F8.2 km/s e_RV [99.99] Error of RV (not used)
117-122 I6 --- n_RV [] Number of stars used for RV (not used)
123-128 I6 --- N1sr0 Number of most probable (1-σ)
members in r0
129-135 I7 --- N1sr1 Number of most probable (1-σ)
members in r1 (1)
136-142 I7 --- N1sr2 Number of most probable (1-σ)
members in r2
143-150 F8.0 pc d Distance from the Sun
151-157 F7.3 mag E(B-V) Colour-excess in (B-V)
158-164 F7.3 mag MOD Apparent distance modulus, mKs-MKs
165-171 F7.3 mag E(J-Ks) Colour-excess in (J-Ks)
172-178 F7.3 mag E(J-H) Colour-excess in (J-H)
179-185 F7.3 mag deltaH Correction to H mag of fitted isochrone
186-192 F7.3 [yr] logt Logarithm of average age
193-199 F7.3 [yr] e_logt ?=0.000 Error of logt
200-203 I4 --- Nt Number of stars used for logt calculation (2)
204-211 F8.2 pc rc ?=0.00 King' core radius
212-219 F8.2 pc e_rc ?=0.00 Error of core radius
220-227 F8.2 pc rt ?=0.00 King' tidal radius
228-235 F8.2 pc e_rt ?=0.00 Error of tidal radius
236-243 F8.2 pc-2 k ?=0.00 King' normalization factor
244-251 F8.2 pc-2 e_k ?=0.00 Error of normalization factor
253-256 A4 --- Src Source for MWSC list and input parameters (G2)
258-260 A3 --- SType [ ] Source object type
262-269 F8.3 --- [Fe/H] [99.999] Metallicity (not used)
270-276 F7.3 --- e_[Fe/H] [9.99] Error of Metallicity (not used)
277-280 I4 --- n_[Fe/H] [ ] Number of stars used for [Fe/H] (not used)
--------------------------------------------------------------------------------
Note (1): This number of stars is used to compute the average PM.
Note (2): Nt=-1 if logt has been set manually.
-------------------------------------------------------------------------------
Byte-by-byte Description of file: index.dat
-------------------------------------------------------------------------------
Bytes Format Units Label Explanations
-------------------------------------------------------------------------------
1- 4 I04 --- MWSC [5001/5987] MWSC number
6- 22 A17 --- Name NGC, IC or other common designation
24- 24 A1 --- flag Flag of confirmation/no confirmation (G1)
26- 26 A1 --- Type [rs] Object type (r=remnant, s=asterism)
27- 27 A1 --- n_Type [oc] object/candidate
29- 32 A4 --- Src Source for MWSC list and input parameters (G2)
34- 36 A3 --- SType [ ] Source object type (not used)
37- 45 I9 --- N [0/7915] Number of stars in MWSC sky area
--------------------------------------------------------------------------------
Byte-by-byte Description of file: notes.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I04 --- MWSC [5001/5987] MWSC number
6- 14 A9 --- Name MWSC_NNNN
16 A1 --- flag Flag of confirmation/no confirmation (G1)
18 A1 --- Type [rs] Object type (r=remnant, s=asterism)
19 A1 --- n_Type [oc] object/candidate
21-196 A176 --- Note Text of note
--------------------------------------------------------------------------------
Byte-by-byte Description of file: stars/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 F13.8 h RAhour Right Ascension J2000.0, epoch 2000.0
14- 26 F13.7 deg DEdeg Declination J2000.0, epoch 2000.0
27- 34 F8.3 mag Bmag ?=99.990 Blue magnitude (1)
35- 42 F8.3 mag Vmag ?=99.990 Visual or red magnitude (2)
43- 50 F8.3 mag Jmag J magnitude 2MASS
51- 58 F8.3 mag Hmag H magnitude 2MASS
59- 66 F8.3 mag Ksmag Ks magnitude 2MASS
67- 73 F7.3 mag e_Jmag Error of J magnitude
74- 80 F7.3 mag e_Hmag Error of H magnitude
81- 87 F7.3 mag e_Ksmag Error of Ks magnitude
88- 97 F10.2 mas/yr pmRA ?=9999.90 Proper Motion in RA*cos(DE)
98-107 F10.2 mas/yr pmDE ?=9999.90 Proper Motion in DE
108-115 F8.2 mas/yr e_pm ?=-9.99 Error of proper motion
116-124 F9.2 km/s RV ?=999.99 Radial velocity
125-131 F7.2 km/s e_RV ?=-9.99 Error of RV
133-135 A3 --- Qflg 2MASS (ph_qual) JHKs Photometric quality flag
136-138 A3 --- Rflg 2MASS (rd_flg) Source of JHKs default mag
139-141 A3 --- Bflg 2MASS (bl_flg) JHKs components fit to source
146-155 I10 --- 2MASS 2MASS (pts_key) Unique identifier in 2MASS
156-163 I8 --- ASCC ?=0 ASCC-2.5 number (Cat. I/280)
165-184 A20 --- SpType Spectral type and luminosity class
186-193 F8.4 deg Rcl Angular distance from cluster centre
194-195 I2 --- Ps [0/1] Spatial membership probability
196-203 F8.2 % Pkin [0/100] Proper motion membership probability
204-211 F8.2 % PJKs [0/100] Photometric JKs membership probability
212-219 F8.2 % PJH [0/100] Photometric JH membership probability
221-224 I04 --- MWSC [5001/5987] MWSC number of cluster
--------------------------------------------------------------------------------
Note (1): Blue magnitude, if the star is in the ASCC-2.5 (ASCC is not equal 0),
then this is the Johnson B magnitude from ASCC-2.5;
if the star is not in the ASCC-2.5 (ASCC = 0), then this is the photographic
blue magnitude from USNO-A2.0.
Note (2): Visual or red magnitude, if the star is in the ASCC-2.5
(ASCC is not equal 0), then this is the Johnson V magnitude from ASCC-2.5;
if the star is not in the ASCC-2.5 (ASCC = 0), then this is the photographic
red magnitude from USNO-A2.0.
--------------------------------------------------------------------------------
Global notes:
Note (G1): This column has the following meaning:
"=" = cluster parameters are determined
":" = possibly this is a cluster, but parameters are not determined
"-" = this is not a cluster
"&" = duplicated/coincides with another cluster
Note (G2): the sources are:
ARIn = Objects with b>18.5°
ARIs = Objects with b←18.5°
ARIa = (unspecified)
--------------------------------------------------------------------------------
Acknowledgements:
Stefan Schmeja, sschmeja(at)ari.uni-heidelberg.de
References:
Kharchenko et al., Paper I 2012A&A...543A.156K 2012A&A...543A.156K, Cat. J/A+A/543/A156
Kharchenko et al., Paper II 2013A&A...558A..53K 2013A&A...558A..53K, Cat. J/A+A/558/A53
History:
* 13-Aug-2014: Original version
* 21-Aug-2015: Corrected definitions for Bmag and Vmag in stars/* files,
from Ralf Scholz
(End) Patricia Vannier [CDS] 27-Jun-2014