J/A+A/575/A120 DANCe study of M35 (NGC 2168) (Bouy+, 2015)
Messier 35 (NGC 2168) DANCe.
I. Membership, proper motions, and multi-wavelength photometry.
Bouy H., Bertin E., Barrado D., Sarro L.M., Olivares J., Moraux E.,
Bouvier J., Cuillandre J.-C., Ribas A., Beletsky Y.
<Astron. Astrophys. 575, A120 (2015)>
=2015A&A...575A.120B 2015A&A...575A.120B
ADC_Keywords: Clusters, open ; Photometry, infrared ; Proper motions
Keywords: proper motions - stars: kinematics and dynamics -
Galaxy: open clusters and associations: individual: NGC2168
Abstract:
Messier 35 (NGC 2168) is an important young nearby cluster. Its age,
richness and relative proximity make it a privileged target for
stellar evolution studies. The Kepler K2 mission recently observed it
and provided high accuracy photometric time series of a large number
of sources in this area of the sky. Identifying the cluster's
members is therefore of high importance to optimize the interpretation
and analysis of the Kepler K2 data.
We aim at identifying the cluster's members by deriving membership
probabilities for the sources within 1 degree of the cluster's
center, going further away than equivalent previous studies.
We measure accurate proper motions and multi-wavelength (optical and
near-infrared) photometry using ground based archival images of the
cluster. We use these measurements to compute membership
probabilities. The list of candidate members from Barrado y Navascues et al.
(2001ApJ...546.1006B 2001ApJ...546.1006B, Cat. J/ApJ/546/1006) is used as training set to
identify the cluster's locus in a multi-dimensional space made of
proper motions, luminosities and colors.
The final catalog includes 338892 sources with multi-wavelength
photometry. Approximately half (194452) were detected at more than two
epochs and we measured their proper motion and used it to derive
membership probability. A total of 4349 candidate members with
membership probabilities greater than 50% are found in this sample in
the luminosity range between 10 and 22mag. The slow proper motion of
the cluster and the overlap of its sequence with the field and
background sequences in almost all color-magnitude and color-color
diagrams complicate the analysis and the contamination level is
expected to be significant. Our study nevertheless provides a coherent
and quantitative membership analysis of Messier 35 based on a large
fraction of the best ground-based data sets obtained over the past 18
years. As such, it represents a valuable input for follow-up studies
using in particular the Kepler K2 photometric time series.
Description:
Position, proper motion and multi-wavelength grizJHK photometry for
338892 sources within 1° of Messier 35 center. Membership to
Messier 35 is available for 194452 of them.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 240 338392 Position, proper motion and multi-wavelength
grizJHK photometry for 338892 sources within
1degree of Messier 35 center
DANCe_M35.fits 2880 28088 FITS version of table3
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See also:
J/MNRAS/306/361 : UBVI CCD photometry of M35 (NGC 2168) (Sung+ 1999)
J/ApJ/546/1006 : VRI photometry of M35 (Barrado y Navascues+, 2001)
J/ApJ/695/679 : Stellar rotation in M35 (Meibom+, 2009)
J/AJ/139/1383 : Radial velocities in M35 (NGC 2168) (Geller+, 2010)
J/AJ/148/85 : WIYN open cluster study. Photometry of M35 (Thompson+, 2014)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- DANCe DANCe designation (HHMMSSss+DDMMSSs) (2)
17 A1 --- m_DANCe [abc] Non-unique DANCe name (2)
19- 22 I4 --- Nep [1/1564] Total number of epochs
24- 27 I4 --- Npm [1/1564] Number of epochs used for the
proper motion fit
29- 38 F10.6 deg RAdeg Right ascension (J2000), at Epoch
40- 49 F10.6 deg DEdeg Declination (J2000), at Epoch
51- 58 F8.6 deg e_RAdeg rms uncertainty on RAdeg
60- 67 F8.6 deg e_DEdeg rms uncertainty on DEdeg
69- 76 F8.2 mas/yr pmRA ?=- Proper motion along RA (pmRA*cosDE) (1)
78- 85 F8.2 mas/yr pmDE ?=- Proper motion along DE (1)
87- 92 F6.2 mas/yr e_pmRA ?=- rms uncertainty on pmRA (1)
94- 99 F6.2 mas/yr e_pmDE ?=- rms uncertainty on pmDE (1)
101-108 F8.2 --- chi2 ?=- Reduced χ2 of the proper motion fit
110-117 F8.3 yr Epoch [1997/2012] Mean epoch of observation
119-126 F8.3 yr b_Epoch Earliest epoch used for the proper motion fit
128-135 F8.3 yr B_Epoch Lastest epoch used for the proper motion fit
137 I1 --- Flags [0/7] Extraction flags (SExtractor flag)
139-144 F6.3 mag gmag ? SDSS g magnitude
146-151 F6.3 mag e_gmag ? rms uncertainty on gmag
153-158 F6.3 mag rmag ? SDSS r magnitude
160-165 F6.3 mag e_rmag ? rms uncertainty on rmag
167-172 F6.3 mag imag ? SDSS i magnitude
174-179 F6.3 mag e_imag ? rms uncertainty on imag
181-186 F6.3 mag zmag ? SDSS z magnitude
188-193 F6.3 mag e_zmag ? rms uncertainty on zmag
195-200 F6.3 mag Jmag ? 2MASS J magnitude
202-207 F6.3 mag e_Jmag ? rms uncertainty on Jmag
209-214 F6.3 mag Hmag ? 2MASS H magnitude
216-221 F6.3 mag e_Hmag ? rms uncertainty on Hmag
223-228 F6.3 mag Kmag ? 2MASS Ks magnitude
230-235 F6.3 mag e_Kmag ? rms uncertainty on Kmag
237-240 F4.2 --- Mm [0/1]? Membership probability
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Note (1): huge values of the proper motion and their errors are truncated
here at ±9999.99mas/yr for the proper motion components, and
999.99 for the errors.
Note (2): 859 DANCe names are not unique -- a suffix "a" or "b" was added
at CDS
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Acknowledgements:
Herve Bouy, hbouy(at)cab.inta-csic.es
History:
* 20-Jan-2015: FITS table version, from author
* 01-Aug-2015: in the ascii version of the table, the huge values and
errors of the proper motion are truncated, and the suffix m_DANCe
was added for colliding DANCe names.
(End) Patricia Vannier [CDS] 20-Jan-2015