J/A+A/586/A52 NGC 2264, NGC 2547 and NGC 2516 stellar radii (Jackson+, 2016)
The Gaia-ESO Survey: Stellar radii in the young open clusters
NGC 2264, NGC 2547 and NGC 2516.
Jackson R.J., Jeffries R.D., Randich S., Bragaglia A., Carraro G.,
Costado M.T., Flaccomio E., Lanzafame , Lardo C., Monaco L., Morbidelli L.,
Smiljanic R., Zaggia S.
<Astron. Astrophys. 586, A52 (2016)>
=2016A&A...586A..52J 2016A&A...586A..52J (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, diameters
Keywords: stars: rotation - stars: low-mass - stars: activity -
open clusters and associations: NGC 2264 -
open clusters and associations: NGC 2547 -
open clusters and associations: NGC 2516
Abstract:
Rapidly rotating, low-mass members of eclipsing binary systems have
measured radii that are significantly larger than predicted by
standard evolutionary models. It has been proposed that magnetic
activity is responsible for this radius inflation.
By estimating the radii of low-mass stars in three young clusters
(NGC 2264, NGC 2547, NGC 2516, with ages of ∼5, ∼35 and
∼140Myr respectively), we aim to establish whether similar radius
inflation is seen in single, magnetically active stars.
We use radial velocities from the Gaia-ESO Survey (GES) and published
photometry to establish cluster membership and then combine GES
measurements of projected equatorial velocities with published
rotation periods to estimate the average radii for groups of
fast-rotating cluster members as a function of their luminosity and
age. The average radii are compared with the predictions of both
standard evolutionary models and variants that include magnetic
inhibition of convection and starspots.
Description:
File Table1.dat contains Photometric and spectroscopic data of GES
Survey targets in clusters in NGC 2547, NGC 2516, NGC 22264 downloaded
from the Edinburugh GES archive (http://ges/roe.ac.uk/) .
Photometric data comprised the (Cousins) I magnitude and 2MASS J, H
and K magnitudes.
Spectroscopic data comprises the signal to noise ratio, S/N of the
target spectrum, the radial velocity, RV (in km/s), the projected
equatorial velocity, vsini (in km/s), the number of separate
observations co-added to produce the target spectrum and the log of
effective temperature (logTeff) of the template spectrum fitted to
measure RV and vsini.
The absolute precision in RV, pRV (in km/s) and relative precision
vsini (pvsini) were estimated, as a function of the logTeff, vsini
and S/N, using the prescription described in Jackson et al.
(2015A&A...580A..75J 2015A&A...580A..75J, Cat. J/A+A/580/A75).
File Table3.dat contains measured and calculated properties of cluster
targets with resolved vsini and a reported rotation period.
The cluster name, right ascension, RA (deg) and declination, Dec (deg)
are given for targets with measured periods given in the literature.
Dynamic properties comprise: the radial velocity, RV (in km/s), the
absolute precision in RV, pRV (km/s), the projected equatorial
velocity, vsini (in km/s), the relative precision in vsini (pvsini)
and the rotational period (in days).
Also shown are values of absolute K magnitude, MK log of luminosity,
log L (in solar units) and probability of cluster membership estimated
using cluster data given in the text.
Period shows reported values of cluster taken from the literature
Estimated values of the projected radius, Rsini (in Rsolar) and
uncertainty in projected radius, e_Rsini (in Rsolar) are given for
targets where vsini>5km/s and pvsini>0.2.
The final column shows a flag which is set to 1 for targets in cluster
NGC 2264 where a (H-K) versus (J-H) colour-colour plot indicates
possible infra-red excess.
Period shows reported values of cluster taken from the literature
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 2755 Photometric and spectroscopic data of GES Survey
targets in clusters in NGC 2547, NGC 2516, NGC 22264
downloaded from the Edinburugh GES archive
table3.dat 85 387 Measured and calculated properties of cluster targets
with resolved vsini and a reported rotation period
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Cluster Name of cluster
9- 24 A16 --- Object Name of target (HHMMSSss+DDMMSSs, J2000)
26- 30 F5.2 mag Icmag ?=- Relative I magnitude (Cousins)
32- 36 F5.2 mag Jmag Relative Jmag from 2MASS
38- 42 F5.2 mag Hmag Relative Hmag from 2MASS
44- 48 F5.2 mag Kmag Relative Kmag from 2MASS
50- 55 F6.2 --- S/N Signal to noise ratio
57- 63 F7.2 km/s RV Radial velocity
65- 70 F6.2 km/s vsini Projected equatorial velocity
72- 76 F5.3 [K] logTeff Log of effective temperature
78- 79 I2 --- Nsp Number of spectra co-added
81- 86 F6.2 km/s pRV ? Precision in RV
88- 92 F5.2 --- pvsini ? Relative precision in vsini
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Cluster Name of cluster
9- 16 F8.4 deg RAdeg Right ascension (J2000)
18- 25 F8.4 deg DEdeg Declination (J2000)
27- 32 F6.2 km/s RV Radial velocity
34- 37 F4.2 km/s pRV Absolute precision in RV
39- 44 F6.2 km/s vsini Projected equatorial velocity
46- 50 F5.2 --- pvsini Relative precision in vsini
52- 55 F4.2 mag KMAG Absolute K magnitude
57- 61 F5.2 [Lsun] logL log of luminosity
63- 66 F4.2 --- Member Estimated probability of membership
68- 72 F5.2 d Period Rotational period
74- 78 F5.2 Rsun Rsini ?=- Esimated value of projected stellar radius
80- 83 F4.2 Rsun e_Rsini ?=- Estimate uncertainty in Rsini
85 I1 --- Flag [1]? Flag of targets with possible
infra-red excess (1)
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Note (1): 1 = (H-K) versus (J-H) colour-colour plot indicates possible
infra-red excess
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Acknowledgements:
Richard Jackson, r.j.jackson(at)keele.ac.uk
(End) Richard Jackson [Keele University], Patricia Vannier [CDS] 20-Nov-2015