We perform a suite of cosmological hydrodynamical simulations of disc galaxies, with zoomed-in initial conditions leading to the formation of a halo of mass M_{halo, DM} ˜eq 2 × 10^{12} M⊙ at redshift z = 0. These simulations aim at investigating the chemical evolution and the distribution of metals in a disc galaxy, and at quantifying the effect of (i) the assumed IMF, (ii) the adopted stellar yields, and (iii) the impact of binary systems originating SNe Ia on the process of chemical enrichment. We consider either a Kroupa, Tout & Gilmore (1993) or a more top-heavy Kroupa (2001) IMF, two sets of stellar yields and different values for the fraction of binary systems suitable to give rise to SNe Ia. We investigate stellar ages, SN rates, stellar and gas metallicity gradients, and stellar α-enhancement in simulations, and compare predictions with observations. We find that a Kroupa et al. (1993) IMF has to be preferred when modelling late-type galaxies in the local Universe. On the other hand, the comparison of stellar metallicity profiles and α-enhancement trends with observations of Milky Way stars shows a better agreement when a Kroupa (2001) IMF is assumed. Comparing the predicted SN rates and stellar α-enhancement with observations supports a value for the fraction of binary systems producing SNe Ia of 0.03, at least for late-type galaxies and for the considered IMFs. Adopted stellar yields are crucial in regulating cooling and star formation, and in determining patterns of chemical enrichment for stars, especially for those located in the galaxy bulge.

Chemical evolution of disc galaxies from cosmological simulations

VALENTINI, MILENA;Borgani, Stefano;Murante, Giuseppe;Tornatore, Luca;Monaco, Pierluigi
2019

Abstract

We perform a suite of cosmological hydrodynamical simulations of disc galaxies, with zoomed-in initial conditions leading to the formation of a halo of mass M_{halo, DM} ˜eq 2 × 10^{12} M⊙ at redshift z = 0. These simulations aim at investigating the chemical evolution and the distribution of metals in a disc galaxy, and at quantifying the effect of (i) the assumed IMF, (ii) the adopted stellar yields, and (iii) the impact of binary systems originating SNe Ia on the process of chemical enrichment. We consider either a Kroupa, Tout & Gilmore (1993) or a more top-heavy Kroupa (2001) IMF, two sets of stellar yields and different values for the fraction of binary systems suitable to give rise to SNe Ia. We investigate stellar ages, SN rates, stellar and gas metallicity gradients, and stellar α-enhancement in simulations, and compare predictions with observations. We find that a Kroupa et al. (1993) IMF has to be preferred when modelling late-type galaxies in the local Universe. On the other hand, the comparison of stellar metallicity profiles and α-enhancement trends with observations of Milky Way stars shows a better agreement when a Kroupa (2001) IMF is assumed. Comparing the predicted SN rates and stellar α-enhancement with observations supports a value for the fraction of binary systems producing SNe Ia of 0.03, at least for late-type galaxies and for the considered IMFs. Adopted stellar yields are crucial in regulating cooling and star formation, and in determining patterns of chemical enrichment for stars, especially for those located in the galaxy bulge.
Pubblicato
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
https://academic.oup.com/mnras/article/485/1/1384/5322187
File in questo prodotto:
File Dimensione Formato  
stz492.pdf

non disponibili

Tipologia: Documento in Versione Editoriale
Licenza: Copyright Editore
Dimensione 11.38 MB
Formato Adobe PDF
11.38 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

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: http://hdl.handle.net/11368/2939866
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 13
  • ???jsp.display-item.citation.isi??? 12
social impact