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# Sulfur abundances in the Galactic bulge and disk

F. Lucertini, L. Monaco, Elisabetta Caffau, Piercarlo Bonifacio, Alessio Mucciarelli

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## To cite this version:

F. Lucertini, L. Monaco, Elisabetta Caffau, Piercarlo Bonifacio, Alessio Mucciarelli. Sulfur abundances in the Galactic bulge and disk. Joint Observatories Kavli Science Forum in Chile (joksfic2022), ESO Santiago, Chile, April 25-29, 2022, Oct 2022, Santiago, Chile. obspm-03812131

HAL Id: obspm-03812131

https://hal-obspm.ccsd.cnrs.fr/obspm-03812131

Submitted on 12 Oct 2022

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# Sulfur abundances
## in the Galactic bulge and disk

F. Lucertini¹,², L. Monaco², E. Caffau³, P. Bonifacio³, A. Mucciarelli⁴,⁵

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francesca.lucertini@eso.org

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@FraLucertini

1. ESO - European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago, Chile

2. Departamento de Ciencias Fisicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Av. Fernandez Concha 700, Las Condes, Santiago, Chile

3. GEPI, Observatoire de Paris, Université PSL, CNRS, Place Jules Janssen, 92195 Meudon, France

4. Dipartimento di Fisica e Astronomia, Università degli Studi di Bologna, Via Gobetti 93/2, 40129 Bologna, Italy

5. INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Gobetti 93/3, 40129 Bologna, Italy

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## MOTIVATION

The measurement of α-element abundances provides a powerful tool for placing constraints on the chemical evolution and star formation history of galaxies. The investigation of sulfur in the Galactic bulge was recently considered for the first time (Griffith+2020). This work aims to improve our knowledge on sulfur behavior in this component of the Milky Way.

## DATA

* Dwarf and sub-giant stars observed during micro-lensing events.

* FLAMES/UVES spectra of 74 Galactic bulge stars.

* FLAMES/UVES spectra of 21 thick-disk stars.

* UVES POP spectra of 30 thin-disk stars.

## RESULTS

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**This work:**

* Galactic bulge stars

* thick-disk stars

* thin-disk stars

**Literature:**

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## METHODS

Sulfur abundances were derived from multiplets 8 (675 nm, left panel), 6 (869 nm, middle panel) and 1 (920 nm, right panel) by spectroscopy or line equivalent widths.

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## CONCLUSIONS

* Sulfur behaves like an α-element in the Galactic bulge.

* Our results for bulge, thick- and thin-disk stars are in agreement within errors with those in the literature.

* We found that the Galactic bulge is sulfur-rich with respect to both the thick- and thin-disks, supporting a more rapid formation and chemical evolution of the Galactic bulge than the disk. On the contrary, Griffith+2020 found similar sulfur behavior for the Galactic bulge and the thick-disk.

**Acknowledgements.**

Support for the author F.L. is provided by CONICYT-PFCHA/Doctorado Nacional año 2020-folio

21200677. E.C. and P.B. acknowledge support from the French National Research Agency (ANR) funded

project "Pristine" (ANR-18-CE31-0017).

**References.**

Griffith, E., Weinberg, D. H., Johnson, J. A., et al. 2021, ApJ, 909, 77
Duffau, S., Caffau, E., Sbordone, L., et al. 2017, A&A, 604, A128
Perdigon, J., de Laverny, P., Recio-Blanco, A., et al. 2021, A&A 647, A162

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