| Title: |
The Gaia-ESO Survey: The inner disc, intermediate-age open cluster Pismis 18 |
| Authors: |
Hatzidimitriou, D; Held, EV; Tognelli, E; Bragaglia, A; Magrini, L; Bravi, L; Gazeas, K; Dapergolas, A; Drazdauskas, A; Delgado-Mena, E; Friel, ED; Minkeviciute, R; Sordo, R; Tautvaisiene, G; Gilmore, G; Randich, S; Feltzing, S; Vallenari, A; Alfaro, EJ; Flaccomio, E; Lanzafame, AC; Pancino, E; Smiljanic, R; Bayo, A; Bergemann, M; Carraro, G; Casey, AR; Costado, MT; Damiani, F; Franciosini, E; Gonneau, A; Jofre, P; Lewis, J; Monaco, L; Morbidelli, L; Worley, CC; Zaggia, S |
| Publisher Information: |
EDP Sciences http://dx.doi.org/10.1051/0004-6361/201834636 ASTRONOMY & ASTROPHYSICS 2019-07-05T23:31:12Z 2019-07-05T23:31:12Z 2019 |
| Document Type: |
Electronic Resource |
| Abstract: |
Pismis 18 is a moderately populated, intermediate-age open cluster located within the solar circle at a Galactocentric distance of about 7 kpc. Few open clusters have been studied in detail in the inner disc region before the Gaia-ESO Survey. New data from the Gaia-ESO Survey allowed us to conduct an extended radial velocity membership study as well as spectroscopic metallicity and detailed chemical abundance measurements for this cluster. Gaia-ESO Survey data for 142 potential members, lying on the upper MS and on the red clump, yielded radial velocity measurements, which, together with proper motion measurements from the Gaia DR2, were used to determine the systemic velocity of the cluster and membership of individual stars. Photometry from Gaia DR2 was used to re-determine cluster parameters based on high confidence member stars only. Cluster abundance measurements of six radial-velocity member stars with UVES high-resolution spectroscopy are presented for 23 elements. According to the new estimates, based on high confidence members, Pismis 18 has an age of $700^{+40}_{-50}$ Myr, interstellar reddening of E(B-V) = $0.562^{+0.012}_{-0.026}$ mag and a de-reddened distance modulus of $DM_0 = 11.96^{+0.10}_{-0.24}$ mag. The median metallicity of the cluster (using the six UVES stars) is [Fe/H] = $+0.23 \pm 0.05$ dex, with [$\alpha$/Fe]= $0.07 \pm 0.13$ and a slight enhancement of s- and r- neutron-capture elements. With the present work, we fully characterized the open cluster Pismis 18, confirming its present location in the inner disc. We estimated a younger age than the previous literature values and gave, for the first time, its metallicity and its detailed abundances. Its [$\alpha$/Fe] and [s-process/Fe], both slightly super-solar, are in agreement with other inner-disc open clusters observed by the Gaia-ESO survey. [abridged] |
| Index Terms: |
stars: abundances; open clusters and associations: individual: Pismis 18; Galaxy: abundances; Galaxy: formation Galaxy: disk; Article |
| URL: |
https://www.repository.cam.ac.uk/handle/1810/294426 |
| Availability: |
Open access content. Open access content; All rights reserved |
| Note: |
application/pdf; English |
| Other Numbers: |
HS1 oai:www.repository.cam.ac.uk:1810/294426; 10.17863/CAM.41525; 1489040359 |
| Contributing Source: |
UNIV OF CAMBRIDGE; From OAIster®, provided by the OCLC Cooperative. |
| Accession Number: |
edsoai.on1489040359 |
| Database: |
OAIster |