J/A+A/649/A178 NGC6791 V604 Lyr disentangled component spectra (Brogaard+, 2021)
Age and helium content of the open cluster NGC6791 from multiple eclipsing
binary members. III. Constraints from a subgiant.
Brogaard K., Grundahl F., Sandquist E.L., Slumstrup D., Jensen M.L.,
Thomsen J.B., Joergensen J.H., Larsen J.R., Bjoern S.T., Soerensen C.T.G.,
Bruntt H., Arentoft T., Frandsen S., Jessen-Hansen J., Orosz J.A.,
Mathieu R., Geller A., Ryde N., Stello D., Meibom S., Platais I.
<Astron. Astrophys. 649, A178 (2021)>
=2021A&A...649A.178B 2021A&A...649A.178B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Binaries, spectroscopic ; Spectroscopy
Keywords: binaries: spectroscopic - stars: fundamental parameters -
stars: individual: V604 Lyr - stars: abundances -
open clusters and associations: individual: NGC 6791
Abstract:
Models of stellar structure and evolution can be constrained using
accurate measurements of the parameters of eclipsing binary members
of open clusters. Multiple binary stars provide the means to tighten
the constraints, and in turn, to improve the precision and accuracy
of the age estimate of the host cluster.
In the previous two papers of this series, we demonstrated the use of
measurements of multiple eclipsing binaries in the old open cluster
NGC6791 to set tighter constraints on the properties of stellar models
than was previously possible, thereby improving both the accuracy and
precision of the cluster age.
We identify and measure the properties of a non-eclipsing cluster
member, V56 (Cl* NGC 6791 KR V56), in NGC 6791 and demonstrate how
this provides additional model constraints that support and strengthen
our previous findings.
We analyse multi-epoch spectra of V56 from FLAMES in conjunction with
the existing photometry and measurements of eclipsing binaries in
NGC6971.
The parameters of the V56 components are found to be
Mp=1.103±0.008M☉ and Ms=0.974±0.007M☉,
Rp=1.764±0.099R☉ and Rs=1.045±0.057R☉,
Teff,p=5447±125K and Teff,s=5552±125K, and surface
[Fe/H]=+0.29±0.06 assuming that they have the same abundance.
The derived properties strengthen our previous best estimate of the
cluster age of 8.3±0.3Gyr and the mass of stars on the lower RGB,
MRGB=1.15±0.02M☉ for NGC 6791. These numbers therefore
continue to serve as verification points for other methods of age and
mass measures, such as asteroseismology.
Description:
Disentangled and renormalised spectra of the two components of the SB2
spectroscopic binary V56 in NGC6791 oversampled to a resolution of
∼1km/s. The spectra used are observed with FLAMES at the VLT in a
setting providing a wavelength range from 5335 to 5611 Angstrom at a
resolution of R∼15000. More details in the article, where the spectra
are shown in Fig. 5.
Objects:
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RA (2000) DE Designation(s)
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19 20 45.26 +37 45 48.6 V604 Lyr = Cl* NGC 6791 KR V56
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 29 151410 Disentangled spectrum of V56 (V604 Lyr)
subgiant component
tablea2.dat 29 151410 Disentangled spectrum of V56 (V604 Lyr)
MS component
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See also:
J/A+A/525/A2 : Eclipsing binaries in NGC6791 (Brogaard+, 2011)
J/A+A/543/A106 : UBVRI photometry in NGC6791 (Brogaard+, 2012)
Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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8- 16 F9.4 0.1nm lambda Wavelength in Angstrom
22- 29 F8.6 --- Flux Normalised flux
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Acknowledgements:
Karsten Brogaard, kfb(at)phys.au.dk
References:
Brogaard et al., Paper I 2011A&A...525A...2B 2011A&A...525A...2B, Cat. J/A+A/525/A2
Brogaard et al., Paper II 2012A&A...543A.106B 2012A&A...543A.106B, Cat. J/A+A/543/A106
(End) K. Brogaard [Aarhus University, Denmark], P. Vannier [CDS] 29-Apr-2021