Publication: The Gaia-ESO survey: galactic evolution of lithium from iDR6
Full text at PDC
Gutiérrez Albarrán, M.L.
Jiménez Esteban, F. M.
Advisors (or tutors)
Context. After more than 50 years, astronomical research still struggles to reconstruct the history of lithium enrichment in the Galaxy and to establish the relative importance of the various ^(7)Li sources in enriching the interstellar medium (ISM) with this fragile element. Aims. To better trace the evolution of lithium in the Milky Way discs, we exploit the unique characteristics of a sample of open clusters (OCs) and field stars for which high-precision ^(7)Li abundances and stellar parameters are homogeneously derived by the Gaia-ESO Survey (GES). Methods. We derive possibly un-depleted ^(7)Li abundances for 26 OCs and star forming regions with ages from young (∼3 Myr) to old (∼4.5 Gyr), spanning a large range of galactocentric distances, 5 < R_(GC)/kpc < 15, which allows us to reconstruct the local late Galactic evolution of lithium as well as its current abundance gradient along the disc. Field stars are added to look further back in time and to constrain ^(7)Li evolution in other Galactic components. The data are then compared to theoretical tracks from chemical evolution models that implement different ^(7)Li forges. Results. Thanks to the homogeneity of the GES analysis, we can combine the maximum average ^(7)Li abundances derived for the clusters with ^(7)Li measurements in field stars. We find that the upper envelope of the 7Li abundances measured in field stars of nearly solar metallicities (−0.3 < [Fe/H]/dex < +0.3) traces very well the level of lithium enrichment attained by the ISM as inferred from observations of cluster stars in the same metallicity range. We confirm previous findings that the abundance of ^(7)Li in the solar neighbourhood does not decrease at super-solar metallicity. The comparison of the data with the chemical evolution model predictions favours a scenario in which the majority of the ^(7)Li abundance in meteorites comes from novae. Current data also seem to suggest that the nova rate flattens out at later times. This requirement might have implications for the masses of the white dwarf nova progenitors and deserves further investigation. Neutrino-induced reactions taking place in core-collapse supernovae also produce some fresh lithium. This likely makes a negligible contribution to the meteoritic abundance, but could be responsible for a mild increase in the ^(7)Li abundance in the ISM of low-metallicity systems that would counterbalance the astration processes.
© ESO 2021. Artículo firmado por 34 autores. This work is based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme IDs 188.B-3002, 193.B-0936, and 197.B-1074. These data products have been processed by the Cambridge Astronomy Survey Unit (CASU) at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF, Osservatorio Astrofisico di Arcetri. These data have been obtained from the Gaia-ESO Survey Data Archive, prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and from the Italian Ministry of Education, University and Research (Ministero dell’Istruzione, dell’Università e della Ricerca, MIUR) in the form of the grant Premiale VLT 2012. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. LM, SR, GCas and AB acknowledges funding from MIUR Premiale 2016 MITiC. PB acknowledges support from the French National Research Agency (ANR) funded project “Pristine” (ANR-18-CE31-0017). VG acknowledges financial support at SISSA from the European Social Fund operational Programme 2014/2020 of the autonomous region Friuli Venezia Giulia. TB was funded by grant No. 2018-04857 from The Swedish Research Council. AJK acknowledges support from the Swedish National Space Agency (SNSA/Rymdstyrelsen). SLM is supported by funding from the Australian Research Council via Discovery Project DP180101791 and from the UNSW Scientia Fellowship program. FJE acknowledges financial support from the Spanish MINECO/FEDER through the grant AYA2017-84089 and MDM-2017-0737 at Centro de Astrobiología (CSIC-INTA), Unidad de Excelencia María de Maeztu, and from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 824064 through the ESCAPE - The European Science Cluster of Astronomy and Particle Physics ESFRI Research Infrastructures project.