We report the spectroscopic discovery of abundance spreads (i.e. multiple populations) in the 1/42 Gyr old cluster in the LMC, Hodge 6. We use low-resolution VLT FORS2 spectra of 15 member stars in the cluster to measure their CN and CH band strengths at ' 3883 and 4300 Å, respectively, as well as [C/Fe] and [N/Fe] abundances. We find a subpopulation of two stars that are enriched in nitrogen, and we conclude that this subpopulation is evidence of multiple populations in Hodge 6. This is the second 1/42 Gyr old cluster (the first being NGC 1978 in the LMC) to show multiple populations and the first spectroscopic detection of MPs in a cluster of this age. This result is interesting as it hints at a possible relationship between the disappearance of extended main sequence turn-offs in clusters younger than 1/42 Gyr and the onset of multiple populations at 1/42 Gyr, which should be explored further.

Spectroscopic detection of multiple populations in the er Hodge 6 in the LMC

Lardo C.;Mucciarelli A.;
2019

Abstract

We report the spectroscopic discovery of abundance spreads (i.e. multiple populations) in the 1/42 Gyr old cluster in the LMC, Hodge 6. We use low-resolution VLT FORS2 spectra of 15 member stars in the cluster to measure their CN and CH band strengths at ' 3883 and 4300 Å, respectively, as well as [C/Fe] and [N/Fe] abundances. We find a subpopulation of two stars that are enriched in nitrogen, and we conclude that this subpopulation is evidence of multiple populations in Hodge 6. This is the second 1/42 Gyr old cluster (the first being NGC 1978 in the LMC) to show multiple populations and the first spectroscopic detection of MPs in a cluster of this age. This result is interesting as it hints at a possible relationship between the disappearance of extended main sequence turn-offs in clusters younger than 1/42 Gyr and the onset of multiple populations at 1/42 Gyr, which should be explored further.
2019
Hollyhead K.; Martocchia S.; Lardo C.; Bastian N.; Kacharov N.; Niederhofer F.; Cabrera-Ziri I.; Dalessandro E.; Mucciarelli A.; Salaris M.; Usher C.
File in questo prodotto:
File Dimensione Formato  
stz317.pdf

accesso aperto

Tipo: Versione (PDF) editoriale
Licenza: Licenza per accesso libero gratuito
Dimensione 1.5 MB
Formato Adobe PDF
1.5 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/740145
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 25
  • ???jsp.display-item.citation.isi??? 24
social impact