J/AJ/143/41 UBVIc CCD photometry of star clusters Tr14 and Tr16 (Hur+, 2012)
Distance and the initial mass function of young open clusters in the
η Carina Nebula: Tr 14 and Tr 16.
Hur H., Sung H., Bessell M.S.
<Astron. J., 143, 41 (2012)>
=2012AJ....143...41H 2012AJ....143...41H
ADC_Keywords: Clusters, open ; Photometry, CCD ; Photometry, UBVRI ;
Cross identifications
Keywords: open clusters and associations: individual (Trumpler 14,
Trumpler 16) - stars: luminosity function, mass function -
stars: pre-main sequence
Abstract:
We present new UBVIc CCD photometry of the young open clusters
Trumpler 14 (Tr 14) and Trumpler 16 (Tr 16) in the η Carina Nebula
(NGC 3372). We also identify the optical counterpart of Chandra X-ray
sources and Two Micron All Sky Survey point sources. The members of
the clusters were selected from the proper-motion study, spectral
types, reddening characteristics, and X-ray or near-IR excess
emission. An abnormal reddening law RV,cl=4.4±0.2 was obtained for
the stars in the η Carina Nebula using the 141 early-type stars
with high proper-motion membership probability (Pµ≥70%). We
determined the distance to each cluster and conclude that Tr 14 and
Tr 16 have practically the same distance modulus of
V0-MV=12.3±0.2mag (d=2.9±0.3kpc). The slope of the initial
mass function was determined to be Γ=-1.3±0.1 for Tr 14,
Γ=-1.3±0.1 for Tr 16, and Γ=-1.4±0.1 for all members
in the observed region for the stars with log m≥0.2. We also
estimated the age of the clusters to be about 1-3Myr from the
evolutionary stage of evolved stars and low-mass pre-main-sequence
stars.
Description:
We selected the members and candidates using the X-ray source catalog
from Chandra X-ray observations provided by Albacete-Colombo et al.
(2008, Cat. J/A+A/490/1055) and the CCCP X-ray point-source catalog
provided by Broos et al. (2011, Cat. J/ApJS/194/2), the 2MASS
point-source catalog (Cat. II/246), and the membership probability
from the proper-motion study of Cudworth et al. (1993, Cat. J/AJ/105/1822).
UBVIc observations were performed on 1997 March 2, June 23, 1999
February 5 and 6 using the 1m telescope at Siding Spring Observatory.
The total observed area covered 22.4'x20.8' of the nebula.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 110 4543 Photometric data
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2013)
B/chandra : The Chandra Archive Log (CXC, 1999-2013)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/194/9 : X-ray star clusters in the Carina complex (Feigelson+, 2011)
J/ApJS/194/10 : NIR properties of YSO in the CCCP (Preibisch+, 2011)
J/ApJS/194/2 : Chandra Carina Complex Project (CCCP) catalog (Broos+, 2011)
J/MNRAS/407/2109 : Kinematic study of open clusters (Vande Putte+, 2010)
J/A+A/515/A26 : H and Ks photometry of Trumpler 14 (Sana+, 2010)
J/other/NewA/15.108 : UBVRIHα of η Car (Fernandez-Lajus+ 2010)
J/A+A/493/1093 : BVRI light curves of η Car (Fernandez-Lajus+, 2009)
J/A+A/490/1055 : Tr 16 low-mass stars in Chandra (Albacete-Colombo+, 2008)
J/ApJ/667/963 : Near-infrared photometry of Carina nebula (Sanchawala+ 2007)
J/A+A/476/199 : Trumpler 14 JHKL' photometry (Ascenso+, 2007)
J/MNRAS/367/513 : JHKs[3.5][4.5] photometry of NGC 3372 (Tapia+, 2006)
J/A+A/418/525 : Collinder 232 & Tr 14/16 UBVRI photometry (Carraro+, 2004)
J/ApJ/549/578 : BV photometry of Trumpler 14 and 16 (Degioia-Eastwood+ 2001)
J/A+AS/116/75 : Region of the open cluster Tr 14 (Vazquez+, 1996)
J/AJ/105/980 : Stellar content of Tr 14 and Tr 16 (Massey+, 1993)
J/AJ/105/258 : UBVRI polarimetry in Car Nebula (Marraco+ 1993)
J/AJ/105/1822 : Open clusters near eta Car (Cudworth+, 1993)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [1/4543] Object identifier
(<[HSB2012] NNNN> in Simbad)
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 15 F4.1 s RAs Second of Right Ascension (J2000)
17 A1 --- DE- Sign of the Declination (J2000)
18- 19 I2 deg DEd Degree of Declination (J2000)
21- 22 I2 arcmin DEm Arcminute of Declination (J2000)
24- 27 F4.1 arcsec DEs Arcsecond of Declination (J2000)
29- 34 F6.3 mag Vmag [9.2/19] The V band magnitude
36- 41 F6.3 mag U-B ? The (U-B) color index
43- 48 F6.3 mag B-V ? The (B-V) color index
50- 55 F6.3 mag V-I ? The (V-I) color index
57- 61 F5.3 mag e_Vmag Uncertainty in Vmag
63- 67 F5.3 mag e_U-B ? Uncertainty in U-B
69- 73 F5.3 mag e_B-V ? Uncertainty in B-V
75- 79 F5.3 mag e_V-I ? Uncertainty in V-I
81 I1 --- o_Vmag [1/6] Number of V band observations
83 I1 --- o_U-B [0/2] Number of (U-B) observations
85 I1 --- o_B-V [0/6] Number of (B-V) observations
87 I1 --- o_V-I [0/6] Number of (V-I) observations
89- 90 I2 % Mmb ? Membership probability from proper motion (1)
92- 93 A2 --- n_ID [D X I DX XI] Pecularities (2)
95-110 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs, J2000;
Cat. II/246)
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Note (1): From proper motion study of Cudworth et al. (1993, Cat. J/AJ/105/1822)
Note (2): Note as follows:
D = The PSF of the object shows a convolution of two PSFs, but the
object is measured as a single star for the sake of photometric error.
X = X-ray emission star.
I = NIR excess star.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 12-Apr-2013