METALLICITY IN THE GALACTIC CENTER: THE QUINTUPLET CLUSTER

@article{Najarro2008METALLICITYIT,
  title={METALLICITY IN THE GALACTIC CENTER: THE QUINTUPLET CLUSTER},
  author={Francisco Najarro and Donald F. Figer and D. John Hillier and Thomas R. Geballe and Rolf Peter Kudritzki},
  journal={The Astrophysical Journal},
  year={2008},
  volume={691},
  pages={1816 - 1827}
}
We present a measurement of metallicity in the Galactic center Quintuplet cluster made using quantitative spectral analysis of two luminous blue variables (LBVs). The analysis employs line-blanketed non-LTE wind/atmosphere models fit to high-resolution near-infrared spectra containing lines of H, He i, Si ii, Mg ii, and Fe ii. We are able to break the H/He ratio versus mass-loss rate degeneracy found in other LBVs and to obtain robust estimates of the He content of both objects. Our results… 

CHEMICAL ABUNDANCE PATTERNS IN THE INNER GALAXY: THE SCUTUM RED SUPERGIANT CLUSTERS

The location of the Scutum Red Supergiant (RSG) clusters at the end of the Galactic Bar makes them an excellent probe of the Galaxy's secular evolution, while the clusters themselves are ideal

Detailed Abundances in the Galactic Center: Evidence of a Metal-rich Alpha-enhanced Stellar Population

We present a detailed study of the composition of 20 M giants in the Galactic center with 15 of them confirmed to be in the nuclear star cluster. As a control sample we have also observed 7 M giants

On the metallicity distribution of classical Cepheids in the Galactic inner disk

We present homogeneous and accurate iron abundances for almost four dozen (47) of Galactic Cepheids using high-spectral resolution (R ~ 40 000) high signal-to-noise ratio (S/N ≥ 100) optical spectra

Metallicity studies of the Galactic center: evidence for a top-heavy star formation history?

Abstract The Galactic center (GC) region hosts three of the most massive resolved young clusters in the Local Group and constitutes a test bed for studying the star formation history of the region

Chemical Abundances of M giants in the Galactic Center: a Single Metal-Rich Population with Low [alpha/Fe]

Context. The formation and evolution of the Milky Way bulge is still largely an unanswered question. One of the most essential observables needed in its modelling are the metallicity distribution and

Evidence for a metal-poor population in the inner Galactic Bulge

The inner Galactic Bulge has, until recently, been avoided in chemical evolution studies due to extreme extinction and stellar crowding. Large, near-IR spectroscopic surveys, such as APOGEE, allow

Emission Lines in the Near-infrared Spectra of the Infrared Quintuplet Stars in the Galactic Center

We report the detection of a number of emission lines in the 1.0–2.4 μm spectra of four of the five bright-infrared dust-embedded stars at the center of the Galactic center’s (GC) Quintuplet Cluster.

On the α-element gradients of the Galactic thin disk using Cepheids

We present new homogeneous measurements of Na, Al, and three α-elements (Mg, Si, Ca) for 75 Galactic Cepheids. The abundances are based on high spectral resolution (R~ 38 000) and high

On the fine structure of the Cepheid metallicity gradient in the Galactic thin disk

We present homogeneous and accurate iron abundances for 42 Galactic Cepheids based on high resolution (R ~ 38 000) high signal-to-noise ratio (S/N ≥ 100) optical spectra collected with UVES at VLT

The Quintuplet cluster - II. Analysis of the WN stars

Based on K-band integral-field spectroscopy, we analyze four Wolf-Rayet stars of the nitrogen sequence (WN) found in the inner part of the Quintuplet cluster. All WN stars (WR 102d, WR 102i, WR
...

References

SHOWING 1-10 OF 59 REFERENCES

Metallicity in the Galactic Center: The Arches Cluster

We present a quantitative spectral analysis of five very massive stars in the Arches cluster, located near the Galactic center, to determine stellar parameters, stellar wind properties, and, most

Chemical Abundances of Luminous Cool Stars in the Galactic Center from High-Resolution Infrared Spectroscopy

We present chemical abundances in a sample of luminous cool stars located within 30 pc of the Galactic center. Abundances of carbon, nitrogen, oxygen, calcium, and iron were derived from

Stellar Iron Abundances at the Galactic Center

We present measurements of [Fe/H] for six M supergiant stars and three giant stars within 2.5 pc of the Galactic center (GC) and one M supergiant star within 30 pc of the GC. The results are based on

Massive Stars in the Quintuplet Cluster

We present near-infrared photometry and K-band spectra of newly identified massive stars in the Quintuplet cluster, one of the three massive clusters projected within 50 pc of the Galactic center. We

On the α-Element Abundance Gradients in the Disk of the Sculptor Spiral Galaxy NGC 300

We have carried out a detailed spectral analysis of six early B-type supergiants in the Sculptor Group spiral galaxy NGC 300. To this end, we used state-of-the-art unified blanketed non-local

Chemical abundances in the inner 5 kpc of the galactic disk

High-resolution, high signal-to-noise spectral data are presented for four young B-type stars lying towards the Galactic Centre. Determination of their atmospheric parameters from their absorption

Hubble Space Telescope/NICMOS Observations of Massive Stellar Clusters near the Galactic Center

We report Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS) observations of the Arches and Quintuplet clusters, two extraordinary young clusters near the

The First Stellar Abundance Measurements in the Galactic Center: The M Supergiant IRS 7

The first measurement of the photospheric abundances in a star at the Galactic center are presented. A detailed abundance analysis of the Galactic center M2 supergiant IRS 7 was carried out using

Massive Stars in the Arches Cluster

We present and use new spectra and narrowband images, along with previously published broadband images, of stars in the Arches cluster to extract photometry, astrometry, equivalent width, and

The Metallicity and Reddening of Stars in the Inner Galactic Bulge

We present a preliminary analysis of K, J-K color-magnitude diagrams (CMDs) for seven different positions on or close to the minor axis of the Milky Way at Galactic latitudes between +0.°1 and -2.°8.
...