Abundances of Baade’s Window Giants from Keck HIRES Spectra. I. Stellar Parameters and [Fe/H] Values

By Jon P. Fulbright, A. McWilliam, R. Rich. 2005

150 citations recorded by the source corpus.

We present the first results of a new abundance survey of the Milky Way bulge based on Keck HIRES spectra of 27 K giants in the Baade's Window (l = 1°, b = -4°) field. The spectral data used in this study are of much higher resolution and signal-to-noise ratio than previous optical studies of Galactic bulge stars. The [Fe/H] values of our stars, which range between -1.29 and +0.51, were used to recalibrate large low-resolution surveys of bulge stars. Our best value for the mean [Fe/H] of the bulge is -0.10 ± 0.04. This mean value is similar to the mean metallicity of the local disk and indicates that there cannot be a strong metallicity gradient inside the solar circle. The metallicity distribution of stars confirms that the bulge does not suffer from the so-called G dwarf problem. This paper also details the new abundance techniques necessary to analyze very metal-rich K giants, including a new Fe line list and regions of low blanketing for continuum identification.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/1b137fb7adbbc4a7708313db9b053319f385eff9

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Instrumentation

Citations in the corpus

Extragalactic Globular Clusters and Galaxy Formation (2006, methodology): “Fulbright et al. (2006) used Keck/HIRES spectra to recalibrate the metallicity distribution of red clump stars in Baade’s Window (Sadler et al. 1996).”
THE RADIAL VELOCITY EXPERIMENT (RAVE): SECOND DATA RELEASE (2008, result): “The results are consistent with those resulting from the analysis using the excitation temperature and equivalent widths of Fe I and Fe II lines to derive iron abundance, temperature and gravity (Fulbright et al. 2006, 2007).”
Stellar Proper Motions in the Galactic Bulge from Deep Hubble Space Telescope ACS WFC Photometry (2008, background): “A recent spec- troscopic comparisonwith halo objects shows themajority of bulge stars to be -enhanced compared to the halo; thus, themajority bulge stellar population cannot have formed from the halo (Fulbright et al. 2006, 2007).”
Oxygen, Sodium, Magnesium and Aluminium as tracers of the Galactic Bulge Formation (2006, background): “In the red part of the spectrum where our data lies, the CN molecule is one of the worst plagues, making continuum placement and the selection ofclean (i.e. unblended) lines a challenge (see Fulbright et al. 2006 for a description).”
The metal content of bulge field stars from FLAMES-GIRAFFE spectra - I. Stellar parameters and iron abundances (2008, methodology): “The right panel shows the comparison with the spectroscopic IDF for Baade’s Window from Fulbright et al. (2006), as obtained from the recalibration of the Sadler et al. (1996) IDF.”
The Galaxy and its stellar halo: insights on their formation from a hybrid cosmological approach (2008, result): “However, we note that Fulbright et al. (2006) find a slightly more metal-poor distribution for the ‘Baade’s Window’, compared to the distribution found for the same field by Zoccali et al. (2008, plotted in the bottom right panel of Fig.”
Properties of stellar generations in globular clusters and relations with global parameters (2010, methodology): “In the same figure, we also plotted the distribution of field stars from Fulbright (2000), Gratton et al. (2003a), Reddy et al. (2006), Venn et al. (2004) and Fulbright et al. (2003, 2006).”
REDDENING AND EXTINCTION TOWARD THE GALACTIC BULGE FROM OGLE-III: THE INNER MILKY WAY'S RV ∼ 2.5 EXTINCTION CURVE (2012, background): “Spectroscopic investigations of red giants assume photometric temperatures and gravities (Fulbright et al. 2006; Zoccali et al. 2008; De Propris et al. 2011; Hill et al. 2011; Johnson et al. 2011), and thus knowledge of the scale of differential reddening is a prerequisite to making more detailed…”
Chemical similarities between Galactic bulge and local thick disk red giants: O, Na, Mg, Al, Si, Ca, and Ti (2010, background): “Comparison of our equivalent width measurements with lines in common with Fulbright et al. (2006, 2007) for two bulge giant stars: (a) IV-203 and (b) I-322.”
Insights on the Milky Way bulge formation from the correlations between kinematics and metallicity (2010, methodology): “Their study was based on 315 K and M giants with proper motions of Spaenhauer et al. (1992), radial velocities of Sadler et al. (1996) and low-resolution abundances of Terndrup et al. (1995) re-calibrated with the iron abundances scale of Fulbright et al. (2006).”
Chemical Similarities Between Galactic Bulge And Local Thick Disk Red Giant Stars (2008, methodology): “The nature of the Galactic bulge is still unknown since its generally old and metal-rich stellar population (e.g. Zoccali et al. 2006; Fulbright et al. 2006) is consistent with a classical bulge while its boxy shape is indicative of formation by dynamical instability.”
OUR MILKY WAY AS A PURE-DISK GALAXY—A CHALLENGE FOR GALAXY FORMATION (2010, background): “The bulge of our Galaxy is>99% made of stars that are at least 5 Gyr old (Clarkson et al. 2008) with a wide range of metal abundances (McWilliam & Rich 1994; Fulbright et al. 2006; Zoccali et al. 2008).”
The metallicity distribution of bulge clump giants in Baade’s window (2011, methodology): “…lifetime, leading to a correction of −0.02/−0.03 on the MD. Red clump giants are also good candidates for sampling the bulge MD because the CMD region where they stand is known to be hardly contaminated by other Galactic components on the line of sight (Sadler et al. 1996; Fulbright et al. 2006).”
Abundances of Baade’s Window Giants from Keck HIRES Spectra. II. The Alpha and Light Odd Elements (2006, background): “A review of these results, including the implications to the formation of the bulge, will be included in Fulbright et al. (2006b).”
Alpha element abundances and gradients in the Milky Way bulge from FLAMES-GIRAFFE spectra of 650 K giants (2011, background): “…2010, and references therein) and that the formation of the bulge was fast as evidenced by the enhanced alpha elements in bulge stars (McWilliam & Rich 1994; Rich & Origlia 2005; Zoccali et al. 2006; Fulbright et al. 2006, 2007; Lecureur et al. 2007; Meléndez et al. 2008; Ryde et al. 2009, 2010).”