Tracking the Evolution of Lithium in Giants Using Asteroseismology: Super-Li-rich Stars Are Almost Exclusively Young Red-clump Stars

AbstractWe investigate the structure and dynamics of the Milky Way (MW) disk stars based on the analysis of the Apache Point Observatory Galactic Evolution Experiment (APOGEE) data, to infer the past evolution histories of the MW disk component(s) possibly affected by radial migration and/or satellite accretions. APOGEE is the first near-infrared spectroscopic survey for a large number of the MW disk stars, providing their radial velocities and chemical abundances without significant dust extinction effects. We here adopt red-clump (RC) stars (Bovy et al. 2014), for which the distances from the Sun are determined precisely, and analyze their radial velocities and chemical abundances in the MW disk regions covering from the Galactocentric distance, R, of 5 kpc to 14 kpc. We investigate their dynamical properties, such as mean rotational velocities, 〈Vφ〉 and velocity dispersions, as a function of R, based on the MCMC Bayesian method. We find that at all radii, the dynamics of alpha-poor stars, which are candidates of young disk stars, is much different from that of alpha-rich stars, which are candidates of old disk stars. We find that our Jeans analysis for our sample stars reveals characteristic spatial and dynamical properties of the MW disk, which are generally in agreement with the recent independent work by Bovy et al. (2015) but with a different method from ours.

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The core of the Canis Major galaxy as traced by red clump stars

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2005.09973.x ◽

2006 ◽

Vol 366 (3) ◽

pp. 865-883 ◽

Cited By ~ 45

Author(s):

M. Bellazzini ◽

R. Ibata ◽

N. Martin ◽

G. F. Lewis ◽

B. Conn ◽

...

Keyword(s):

The Core ◽

Red Clump

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UVIT-HST-Gaia-VISTA study of KRON 3 in the Small Magellanic Cloud: A cluster with an extended red clump in UV

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab385 ◽

2021 ◽

Author(s):

P K Nayak ◽

A Subramaniam ◽

S Subramanian ◽

S Sahu ◽

C Mondal ◽

...

Keyword(s):

Near Infrared ◽

Spectral Energy Distribution ◽

Variable Mass ◽

Intrinsic Property ◽

Small Variation ◽

Magellanic Cloud ◽

Spectral Energy ◽

Small Range ◽

Small Magellanic Cloud ◽

Red Clump

Abstract We have demonstrated the advantage of combining multi-wavelength observations, from the ultraviolet (UV) to near-infrared, to study Kron 3, a massive star cluster in the Small Magellanic Cloud. We have estimated the radius of the cluster Kron 3 to be 2${_{.}^{\prime}}$0 and for the first time, we report the identification of NUV-bright red clump (RC) stars and the extension of the RC in colour and magnitude in the NUV versus (NUV−optical) colour-magnitude diagram (CMD). We found that extension of the RC is an intrinsic property of the cluster and it is not due to contamination of field stars or differential reddening across the field. We studied the spectral energy distribution of the RC stars, and estimated a small range in temperature ∼5000–5500 K, luminosity ∼60–90 L⊙ and radius ∼8.0–11.0 R⊙ supporting their RC nature. The range of UV magnitudes amongst the RC stars (∼23.3 to 24.8 mag) is likely caused by the combined effects of variable mass loss, variation in initial helium abundance (Yini = 0.23 to 0.28), and a small variation in age (6.5-7.5 Gyr) and metallicity ([Fe/H] = −1.5 to −1.3). Spectroscopic follow-up observations of RC stars in Kron 3 are necessary to confirm the cause of the extended RC.

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Abundance analysis of red clump stars in the old, inner disc, open cluster NGC 4337: a twin of NGC 752?

Astronomy and Astrophysics ◽

10.1051/0004-6361/201424443 ◽

2014 ◽

Vol 568 ◽

pp. A86 ◽

Cited By ~ 9

Author(s):

Giovanni Carraro ◽

Lorenzo Monaco ◽

Sandro Villanova

Keyword(s):

Open Cluster ◽

Red Clump

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Structure of the Large Magellanic Cloud from near infrared magnitudes of red clump stars

Astronomy and Astrophysics ◽

10.1051/0004-6361/201219327 ◽

2013 ◽

Vol 552 ◽

pp. A144 ◽

Cited By ~ 23

Author(s):

S. Subramanian ◽

A. Subramaniam

Keyword(s):

Near Infrared ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Red Clump

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Proper motions in the Galactic bulge: Plaut's window

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308018097 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 351-354

Author(s):

Katherine Vieira ◽

Dana Cassetti-Dinescu ◽

René A. Méndez ◽

R. Michael Rich ◽

Terrence M. Girard ◽

...

Keyword(s):

Proper Motion ◽

Galactic Rotation ◽

Red Giants ◽

Proper Motions ◽

Motion Study ◽

Solar Motion ◽

Two Samples ◽

Red Clump ◽

Good Agreement ◽

Peak Value

AbstractA proper motion study of a field of 20′ × 20′ inside Plaut's low extinction window (l,b)=(0o, −8o), has been completed. Relative proper motions and photographicBVphotometry have been derived for ~ 21,000 stars reaching toV~ 20.5 mag, based on the astrometric reduction of 43 photographic plates, spanning over 21 years of epoch difference. Proper motion errors are typically 1 mas yr−1. Cross-referencing with the 2MASS catalog yielded a sample of ~ 8700 stars, from which predominantly disk and bulge subsamples were selected photometrically from theJHcolor-magnitude diagram. The two samples exhibited different proper-motion distributions, with the disk displaying the expected reflex solar motion. Galactic rotation was also detected for stars between ~2 and ~3 kpc from us. The bulge sample, represented by red giants, has an intrinsic proper motion dispersion of (σl, σb) = (3.39, 2.91)±(0.11, 0.09) mas yr−1, which is in good agreement with previous results. A mean distance of$6.37^{+0.87}_{-0.77}$kpc has been estimated for the bulge sample, based on the observedKmagnitude of the horizontal branch red clump. The metallicity [M/H] distribution was also obtained for a subsample of 60 bulge giants stars, based on calibrated photometric indices. The observed [M/H] shows a peak value at [M/H] ~ −0.1 with an extended metal poor tail and around 30% of the stars with supersolar metallicity. No change in proper motion dispersion was observed as a function of [M/H]. We are currently in the process of obtaining CCDUBV RIphotometry for the entire proper-motion sample of ~ 21,000 stars.

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Environmental Influence on Stellar Evolution: The Horizontal Branch of NGC 1851

Symposium - International Astronomical Union ◽

10.1017/s0074180900001807 ◽

1996 ◽

Vol 174 ◽

pp. 357-358

Author(s):

I. Saviane ◽

G. Piotto ◽

M. Capaccioli ◽

F. Fagotto

Keyword(s):

Mass Loss ◽

Loss Rate ◽

Environmental Influence ◽

Mass Loss Rate ◽

Bimodal Distribution ◽

Age Difference ◽

Horizontal Branch ◽

Cluster Area ◽

The Difference ◽

Red Clump

The bimodal nature of the horizontal branch (HB) of NGC 1851 is known since Stetson (1981). In order to better understand the properties of its HB, we collected a set of data at the ESO-NTT telescope, which provides a full coverage of the cluster area. Additional archive images from the HST-WFPC camera have been used in order to study the central region. The resulting c-m diagram (CMD) for 20500 stars is presented in Fig. 1 (left). Despite its metallicity ([Fe/H]=−1.3), NGC 1851 presents a well defined blue HB tail, besides the expected red clump. The observed CMD has been compared with the synthetic ones. The bimodal HB can be reproduced assuming that there are two stellar populations in the cluster, with an age difference of ∼ 4 Gyr, hypothesis not supported by other properties of the CMD. On the other side, if we assume that the stars in NGC 1851 are 15 Gyr old (as suggested by the difference between the HB and the TO luminosities), only a bimodal mass loss can reproduce the HB morphology: only stars with higher than standard mass loss rate are able to populate the blue-HB (BHB) tail (Fig. 1,left). There are no observational evidences for a bimodal distribution of other parameters (He, CNO, etc.).

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TRACING CHEMICAL EVOLUTION OVER THE EXTENT OF THE MILKY WAY'S DISK WITH APOGEE RED CLUMP STARS

The Astrophysical Journal ◽

10.1088/0004-637x/796/1/38 ◽

2014 ◽

Vol 796 (1) ◽

pp. 38 ◽

Cited By ~ 118

Author(s):

David L. Nidever ◽

Jo Bovy ◽

Jonathan C. Bird ◽

Brett H. Andrews ◽

Michael Hayden ◽

...

Keyword(s):

Chemical Evolution ◽

Red Clump

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The surface mass density in the solar neighbourhood using red clumps stars in TGASxRAVE

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317006524 ◽

2017 ◽

Vol 13 (S334) ◽

pp. 304-305

Author(s):

Jorrit H. J. Hagen ◽

Amina Helmi

Keyword(s):

Vertical Velocity ◽

Velocity Dispersion ◽

Mass Density ◽

Solar Neighbourhood ◽

Local Distribution ◽

Surface Mass ◽

Preliminary Results ◽

Combining Data ◽

Surface Mass Density ◽

Red Clump

AbstractWe investigate the kinematics of red clump stars in the Solar neighbourhood by combining data from the RAVE survey with the TGAS dataset presented in Gaia DR1. Our goal is to put new constraints on the (local) distribution of mass using the Jeans Equations. Here we show the variation of the vertical velocity dispersion as function of height above the mid-plane for both a thin and a thick disk tracer sample and present preliminary results.

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