J/A+A/467/1397 PMS stars in open clusters: the DAY-I Catalogue (Delgado+, 2007)
Pre-main sequence stars in open clusters. I. The DAY-I Catalogue.
Delgado A.J., Alfaro E.J., Yun J.L.
<Astron. Astrophys. 467, 1397 (2007)>
=2007A&A...467.1397D 2007A&A...467.1397D
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; Photometry, UBVRI ;
Photometry, infrared
Keywords: open clusters and associations - stars: pre-main sequence - catalogs
Abstract:
We present the basic ideas and first results from the project we
are carrying out at present, the search for and characterisation of
pre-main sequence (PMS) stars among the members of Galactic young
clusters. The observations of 10 southern clusters, nine of them
located in the Carina-Sagittarius spiral arm of the Milky Way are
presented.
We aim at listing candidate PMS member stars in young clusters.
The catalogued stars will serve as a basis for future spectroscopic
studies of individual objects to determine the properties of stellar
formation in the last phases before the main sequence stage.
Properties such as the presence of residual envelopes or disks,
age spread among PMS members, and the possible presence of several
episodes of star formation in the clusters, are to be addressed.
Multicolour photometry in the UBVRcIc system has been obtained for
10 southern young clusters in the fourth Galactic quadrant, located
between Galactic longitudes l=238 and l=310. For six clusters in the
sample, the observations presented here provide the first published
study based on CCD photometry. A quantitative comparison is performed
with post-MS isochrones, and PMS isochrones from three different
evolutionary models are used in the photometric membership analysis
for possible PMS stars.
The observations produce photometric indices in the Johnson-Cousins
photometric systems for a total of 26962 stars. The matching of our
pixel coordinates with corresponding fields in the 2MASS data base
provides astrometric calibration for all catalogued stars and JHK
2MASS photometric indices for 60% of them. Post-MS cluster ages range
from 4 to 60Myr, whereas the photometric membership analysis assigns
PMS membership assignment to a total of 842 stars, covering an age
range between 1 and 10Myr. This information on the PMS candidate
members has been collected into a catalogue, named DAY-I, which
contains 16 entries for 842 stars in the field of 10 southern
clusters.
Objects:
----------------------------------------------------------------
RA (2000) DE Designation(s) (Nstars)
----------------------------------------------------------------
07 20 06.0 -21 53 00 C0718-218 = NGC 2367 ( 55)
10 35 48.8 -58 13 00 C1033-579 = NGC 3293 ( 83)
10 43 48 -60 05.0 C1041-597 = Cl Collinder 228 (152)
11 10 42 -60 22.0 C1108-601 = Cl Hogg 10 ( 68)
11 11 32.0 -60 22 18 C1109-601 = Cl Hogg 11 (116)
11 11 30 -60 40.0 C1109-604 = Cl Trumpler 18 ( 40)
11 13 00 -60 47.0 C1110-605 = NGC 3590 (129)
12 06 42.7 -61 15 21 C1204-609 = NGC 4103 ( 84)
12 30 00 -64 47.0 C1227-645 = NGC 4463 ( 45)
14 27 47.0 -59 38 24 C1424-594 = NGC 5606 ( 70)
----------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
catalog.dat 104 842 Catalogue of PMS candidates
--------------------------------------------------------------------------------
See also:
J/A+AS/121/223 : PMS candidates in NGC 6611 open cluster (de Winter+ 1997)
Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name IAU cluster number + star number (this work),
CNNNN-NNN-NNNNN
17- 26 F10.6 deg RAdeg Right Ascension (J2000) in decimal degrees
28- 37 F10.6 deg DEdeg Declination (J2000) in decimal degrees
39- 43 F5.2 mag Vmag Johnson V magnitude
45- 49 F5.2 mag U-B ? Johnson U-B colour index
51- 54 F4.2 mag B-V Johnson B-V colour index
56- 59 F4.2 mag V-Rc Johnson-Cousins V-Rc colour index
61- 64 F4.2 mag V-Ic Johnson-Cousins V-Ic colour index
66- 70 F5.2 mag Kmag ? K magnitude (1)
72- 76 F5.2 mag J-H ? J-H colour index (1)
78- 82 F5.2 mag H-K ? H-K colour index (1)
84 I1 --- Mem [1/2] Membership assignment (2)
86- 89 F4.2 mag AV ? Absorption in V band
91- 94 F4.2 [yr] logAge1 ? Age from Siess et al.,
2000A&A...358..593S 2000A&A...358..593S model
96- 99 F4.2 [yr] logAge2 ? Age from Palla et al.,
1999ApJ...525..772P 1999ApJ...525..772P model
101-104 F4.2 [yr] logAge3 ? Age from D'Antona et al.,
1997ApJ...477..519D 1997ApJ...477..519D model
--------------------------------------------------------------------------------
Note (1): JHK colour indices are from 2MASS, transformed to the Bessel system
with formulas by Carpenter, 2001AJ....121.2851C 2001AJ....121.2851C
Note (2): Membership assignment as follows:
1 = membership assignment in 3 CM diagrams, V vs B-V, V-R, and V-I
2 = membership assignment in 4 CM diagrams, V vs U-B, B-V, V-R, and V-I
--------------------------------------------------------------------------------
History:
* 22-Mar-2007: Original version
* 07-Aug-2007: Columns 10 and 11 (J-H and H-K) corrected (from author)
Acknowledgements:
A.J. Delgado, delgado(at)iaa.es
(End) Patricia Vannier [CDS] 22-Mar-2007