Zinc in the Sculptor dwarf spheroidal galaxy

Abstract

From ESO VLT/FLAMES/GIRAFFE spectra, abundance measurements of Zn have been made in $\approx$100 individual red giant branch (RGB) stars in the Sculptor dwarf spheroidal galaxy. This is the largest sample of individual Zn abundance measurements within a stellar system beyond the Milky Way. In the observed metallicity range, $-2.7\le \text{[Fe/H]}\le -0.9$, the general trend of Zn abundances in Sculptor is similar to that of $\alpha$-elements. That is, super-solar abundance ratios of [Zn/Fe] at low metallicities, which decrease with increasing [Fe/H], eventually reaching subsolar values. However, at the higher metallicities in Sculptor, $\text{[Fe/H]}\gtrsim -1.8$, we find a significant scatter, $-0.8\lesssim \text{[Zn/Fe]}\lesssim +0.4$, which is not seen in any $\alpha$-element. Our results are consistent with previous observations of a limited number of stars in Sculptor and in other dwarf galaxies. These results suggest that zinc has a complex nucleosynthetic origin, behaving neither completely like an $\alpha$- nor an iron-peak element.

Accepted in A&A, 14 pages, 16 figures, 8 tables

References in corpus (15)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• A Unified Representation of Gas-Phase Element Depletions in the Interstellar Medium
• Galactic chemical evolution: Carbon through Zinc
• The kinematic status and mass content of the Sculptor dwarf spheroidal galaxy
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• A high resolution VLT/FLAMES study of individual stars in the centre of the Fornax dwarf spheroidal galaxy
• The Chemical Evolution of the Draco Dwarf Spheroidal Galaxy
• Binarity in Carbon-Enhanced Metal-Poor stars
• Limits on Pop III star formation with the most iron-poor stars
• The Araucaria Project. The Distance to the Sculptor dwarf spheroidal galaxy from infrared photometry of RR Lyrae stars
• The first carbon-enhanced metal-poor star found in the Sculptor dwarf spheroidal
• Detailed Abundances of Two Very Metal-Poor Stars in Dwarf Galaxies
• Chemical Signatures of the First Supernovae in the Sculptor Dwarf Spheroidal Galaxy
• Explosion and nucleosynthesis of low redshift pair instability supernovae
• An inefficient dwarf: Chemical abundances and the evolution of the Ursa Minor dwarf spheroidal galaxy

Cited by in corpus (18)

• Zero-metallicity hypernova uncovered by an ultra metal-poor star in the Sculptor dwarf spheroidal galaxy
• Probing the existence of very massive first stars
• High-precision chemical abundances of Galactic building blocks. II. Revisiting the chemical distinctness of the Helmi streams
• Tracing Pop III supernovae with extreme energies through the Sculptor dwarf spheroidal galaxy
• Neutron-capture elements in dwarf galaxies II: Challenges for the s- and i-processes at low metallicity
• Chemical Evolution of R-process Elements in Stars (CERES). I. Stellar parameters and chemical abundances from Na to Zr
• A homogeneous comparison between the chemical composition of the Large Magellanic Cloud and the Sagittarius dwarf galaxy
• A 3D view of dwarf galaxies with Gaia and VLT/FLAMES I. The Sculptor dwarf spheroidal
• Extremely metal-poor stars in the Fornax and Carina dwarf spheroidal galaxies
• Sub-damped Lyman alpha systems in the XQ-100 survey II -- Chemical evolution at 2.4<z<4.3
• Evidence for multiple nucleosynthetic processes from carbon enhanced metal-poor stars in the Carina dwarf spheroidal galaxy
• On the dearth of C-enhanced metal-poor stars in the Galactic bulge
• G112-43/44: A metal-poor binary star with a unique chemical composition and kinematics like the Helmi streams
• Chemical diversity of gas in distant galaxies: The metal and dust enrichment and variations within absorbing galaxies
• XMM-Newton study of the Sculptor dwarf spheroidal galaxy
• A chemical close-up of the main body of the Sagittarius dwarf galaxy
• LAMOST J045019.27+394758.7, with peculiar abundances of N, Na, V, Zn, is possibly a Sculptor dwarf galaxy escapee
• EDGE-INFERNO: How chemical enrichment assumptions impact the individual stars of a simulated ultra-faint dwarf galaxy