Utilizza questo identificativo per citare o creare un link a questo documento:
http://hdl.handle.net/20.500.12386/28775
Titolo: | The GALAH survey: chemical tagging of star clusters and new members in the Pleiades | Autori: | Kos, Janez Bland-Hawthorn, Joss Freeman, Ken Buder, Sven Traven, Gregor De Silva, Gayandhi M. Sharma, Sanjib Asplund, Martin Duong, Ly Lin, Jane Lind, Karin Martell, Sarah Simpson, Jeffrey D. Stello, Dennis Zucker, Daniel B. Zwitter, Tomaž Anguiano, Borja Da Costa, Gary D'ORAZI, VALENTINA Horner, Jonathan Kafle, Prajwal R. Lewis, Geraint MUNARI, Ulisse Nataf, David M. Ness, Melissa Reid, Warren Schlesinger, Katie Ting, Yuan-Sen Wyse, Rosemary |
Data pubblicazione: | 2018 | Rivista: | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | Numero: | 473 | Fascicolo: | 4 | Da pagina:: | 4612 | Abstract: | The technique of chemical tagging uses the elemental abundances of stellar atmospheres to 'reconstruct' chemically homogeneous star clusters that have long since dispersed. The GALAH spectroscopic survey - which aims to observe one million stars using the Anglo-Australian Telescope - allows us to measure up to 30 elements or dimensions in the stellar chemical abundance space, many of which are not independent. How to find clustering reliably in a noisy high-dimensional space is a difficult problem that remains largely unsolved. Here, we explore t-distributed stochastic neighbour embedding (t-SNE) - which identifies an optimal mapping of a high-dimensional space into fewer dimensions - whilst conserving the original clustering information. Typically, the projection is made to a 2D space to aid recognition of clusters by eye. We show that this method is a reliable tool for chemical tagging because it can: (i) resolve clustering in chemical space alone, (ii) recover known open and globular clusters with high efficiency and low contamination, and (iii) relate field stars to known clusters. t-SNE also provides a useful visualization of a high-dimensional space. We demonstrate the method on a data set of 13 abundances measured in the spectra of 187 000 stars by the GALAH survey. We recover seven of the nine observed clusters (six globular and three open clusters) in chemical space with minimal contamination from field stars and low numbers of outliers. With chemical tagging, we also identify two Pleiades supercluster members (which we confirm kinematically), one as far as 6° - one tidal radius away from the cluster centre. | URI: | http://hdl.handle.net/20.500.12386/28775 | URL: | https://academic.oup.com/mnras/article-abstract/473/4/4612/4555384 | ISSN: | 0035-8711 | DOI: | 10.1093/mnras/stx2637 | Bibcode ADS: | 2018MNRAS.473.4612K | Fulltext: | open |
È visualizzato nelle collezioni: | 1.01 Articoli in rivista |
File in questo documento:
File | Descrizione | Dimensioni | Formato | |
---|---|---|---|---|
1709.00794.pdf | preprint | 47.8 MB | Adobe PDF | Visualizza/apri |
stx2637-compr.pdf | Pdf editoriale | 2.83 MB | Adobe PDF | Visualizza/apri |
Page view(s)
72
controllato il 11-set-2024
Download(s)
23
controllato il 11-set-2024
Google ScholarTM
Check
Altmetric
Altmetric
Tutti i documenti in DSpace sono pubblicati ad Accesso Aperto, salvo diversa indicazione per alcuni documenti specifici.