The Chemical Compositions and Evolutionary Status of Red Giants in the Open Cluster NGC 752

Abstract

We present detailed chemical compositions of 10 red giant star members of the Galactic (open) cluster NGC 752, derived from high-resolution (R $\approx$ 60,000), high signal-to-noise ($S/N$ $\ge$ 140) spectra. We confirmed cluster memberships by measuring the stellar radial velocities, and by deriving model atmosphere parameters ($T_{eff}$, logg, [Fe/H] and ${\xi }_t$) from equivalent widths of Fe I, Fe II, Ti I, and Ti II lines. The metallicity we obtained for NGC 752 ([Fe/H]=$-$0.02$\pm$0.05) is in good agreement with previous studies. We derived abundances of $\alpha$ (Mg, Si, Ca), light odd-Z (Na, Al), Fe-group (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn), $n$-capture (Y, La, Nd, Eu), and $p$-capture (Li, C, N, O) species for each star. Furthermore, we also derived abundances of the LiCNO $p$-capture element group and carbon isotopic ratios, using synthetic spectrum analyses of the Li I 6707~Å resonance doublet, the [O I] line at 6300~Å, the CH G-band features near 4311 and 4325 Å, the C${}_2$ bandheads at 5160 and 5631 Å, and ${}^{12,13}$CN red system lines in the 7995$-$8040~Å region. By applying recent isochrones to NGC~752 photometry, and comparing the color-magnitude diagram information to our Li abundances and \ciso\ ratios, we suggest that the 10 observed red giants can be separated into three first-ascent, six red-clump and one red horizontal branch star.

arXiv commentAccepted for publication in MNRAS (19 pages, 15 figures)

References in corpus (37)

• The chemical composition of the Sun
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• The effective temperature scale of FGK stars. II. Teff : color : [Fe/H] calibrations
• A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars
• On the use of empirical bolometric corrections for stars
• Chemical yields from low- and intermediate-mass stars: model predictions and basic observational constraints
• The Victoria-Regina Stellar Models: Evolutionary Tracks and Isochrones for a Wide Range in Mass and Metallicity that Allow for Empirically Constrained Amounts of Convective Core Overshooting
• Improved spectroscopic parameters for transiting planet hosts
• CH in stellar atmospheres: an extensive linelist
• The photospheric solar oxygen project: I. Abundance analysis of atomic lines and influence of atmospheric models
• Thermohaline instability and rotation-induced mixing. I - Low- and intermediate-mass solar metallicity stars up to the end of the AGB
• Elemental Abundance Ratios in Stars of the Outer Galactic Disk. I. Open Clusters
• Low-temperature gas opacity - AESOPUS: a versatile and quick computational tool
• Line lists for the A2PI-X2Sigma+ (red) and {B2Sigma+-X2Sigma} (violet) Systems of CN, 13C14N, and 12C15N, and Application to Astronomical Spectra
• Experimental f-value and isotopic structure for the Ni I line blended with [OI] at 6300A
• Line strengths and updated molecular constants for the C2 Swan system
• Characterizing the Chemistry of the Milky Way Stellar Halo: Detailed Chemical Analysis of a Metal-Poor Stellar Stream
• Chemical abundance analysis of the Open Clusters Berkeley 32, NGC 752, Hyades and Praesepe
• On the metallicity of open clusters II. Spectroscopy
• CNONa and 12C/13C in giants of 10 open clusters
• The Chemical Abundances of Stars in the Halo (CASH) Project. II. A Sample of 16 Extremely Metal-poor Stars
• Oxygen abundances in planet-harbouring stars. Comparison of different abundance indicators
• Silicon and Oxygen Abundances in Planet-Host Stars
• Comprehensive abundance analysis of red giants in the open clusters NGC 752, NGC 1817, NGC 2360 and NGC 2506
• The impact of non-LTE effects and granulation inhomogeneities on the derived iron and oxygen abundances in metal-poor halo stars
• Lithium evolution in intermediate age and old open clusters: NGC 752 revisited
• On the metallicity of open clusters I. Photometry
• Chemical composition of clump stars in the open cluster NGC 6134
• C, N, O abundances and carbon isotope ratios in evolved stars of the open clusters Collinder 261 and NGC 6253
• Chemical composition of evolved stars in the open cluster NGC 2506
• A statistical method to determine open cluster metallicities
• Chemical composition of evolved stars in the open cluster IC 4651
• Chemical compositions of thin-disk, high-metallicity red horizontal-branch field stars
• Oscillator Strength Measurements of Atomic Absorption Lines from Stellar Spectra
• Deriving temperature, mass and age of evolved stars from high-resolution spectra. Application to field stars and the open cluster IC 4651
• Abundance analysis of red clump stars in the old, inner disc, open cluster NGC 4337: a twin of NGC 752?
• Extended Stromgren Photoelectric Photometry in NGC 752

Cited by in corpus (22)

• On the metallicity of open clusters. III. Homogenised sample
• Post first dredge-up [C/N] ratio as age indicator. Theoretical calibration
• NGC 6535: the lowest mass Milky Way globular cluster with a Na-O anti-correlation? Cluster mass and age in the multiple population context
• The OCCASO survey: Presentation and radial velocities of twelve Milky Way Open Clusters
• The Gaia-ESO Survey: properties of newly discovered Li-rich giants
• Tidal tails in the disintegrating open cluster NGC 752
• On Lithium-Rich Red Giants. II. Engulfment on the Giant Branch of Trumpler 20
• The Swift/UVOT Stars Survey. III. Photometry and Color-Magnitude Diagrams of 103 Galactic Open Clusters
• Chemical Compositions of Evolved Stars From Near-Infrared IGRINS High-Resolution Spectra. I. Abundances in Three Red Horizontal Branch Stars
• A uvbyCaHbeta CCD Analysis of the Open Cluster Standard, NGC 752
• Chemical Abundances Of Open Clusters From High-Resolution Infrared Spectra. II. NGC 752
• The chemical compositions and evolutionary status of red giants in the open cluster NGC 6940
• The Gaia-ESO Survey: Inhibited extra mixing in two giants of the open cluster Trumpler 20?
• Lithium in Open Cluster Red Giants Hosting Substellar Companions
• Effective Temperature Estimations from Line Depth Ratios in the \H\ and \K-band Spectra of IGRINS
• A Comparison of the Chemical Composition of Main Sequence and Giant Stars in the Open Cluster NCC 752
• A Spectroscopic Survey of Field Red Horizontal-Branch Stars
• Chemical Compositions of Red Giant Stars from Habitable Zone Planet Finder Spectroscopy
• On the validity of the spectroscopic age indicators [Y/Mg], [Y/Al], [Y/Si], [Y/Ca], and [Y/Ti] for giant stars
• On Lithium-6 as diagnostic of the lithium-enrichment mechanism in red giants
• Evolved Eclipsing Binaries and the Age of the Open Cluster NGC 752
• Stellar Population Astrophysics (SPA) with the TNG: NLTE atmospheric parameters and abundances of giant stars in 33 Open Clusters