The evolution of the metallicity gradient and the star formation efficiency in disc galaxies. Sillero, E., Tissera, P. B., Lambas, D. G., & Michel-Dansac, L. ArXiv e-prints, 1709:arXiv:1709.00438, September, 2017.
The evolution of the metallicity gradient and the star formation efficiency in disc galaxies [link]Paper  abstract   bibtex   
We study the oxygen abundance profiles of the gas-phase components in hydrodynamical simulations of pre-prepared disc galaxies including major mergers, close encounters and isolated configurations. We analyse the evolution of the slope of oxygen abundance profiles and the specific star formation rate (sSFR) along their evolution. We find that galaxy-galaxy interactions could generate either positive and negative gas-phase oxygen profiles depending on the state of evolution. Along the interaction, galaxies are found to have metallicity gradients and sSFR consistent with observations, on average. Strong gas inflows produced during galaxy-galaxy interactions or as a result of strong local instabilities in gas-rich discs are able to produce both a quick dilution of the central gas-phase metallicity and a sudden increase of the sSFR. Our simulations show that, during these events, a correlation between the metallicity gradients and the sSFR can be set up if strong gas inflows are triggered in the central regions in short timescales. Simulated galaxies without experiencing strong disturbances evolve smoothly without modifying the metallicity gradients. Gas-rich systems show large dispersion along the correlation. The dispersion in the observed relation could be interpreted as produced by the combination of galaxies with different gas-richness and/or experiencing different types of interactions. Hence, our findings suggest that the observed relation might be the smoking gun of galaxies forming in a hierarchical clustering scenario.
@article{sillero_evolution_2017,
	title = {The evolution of the metallicity gradient and the star formation efficiency in disc galaxies},
	volume = {1709},
	url = {http://adsabs.harvard.edu/abs/2017arXiv170900438S},
	abstract = {We study the oxygen abundance profiles of the gas-phase components in 
hydrodynamical simulations of pre-prepared disc galaxies including major
mergers, close encounters and isolated configurations. We analyse the
evolution of the slope of oxygen abundance profiles and the specific
star formation rate (sSFR) along their evolution. We find that
galaxy-galaxy interactions could generate either positive and negative
gas-phase oxygen profiles depending on the state of evolution. Along the
interaction, galaxies are found to have metallicity gradients and sSFR
consistent with observations, on average. Strong gas inflows produced
during galaxy-galaxy interactions or as a result of strong local
instabilities in gas-rich discs are able to produce both a quick
dilution of the central gas-phase metallicity and a sudden increase of
the sSFR. Our simulations show that, during these events, a correlation
between the metallicity gradients and the sSFR can be set up if strong
gas inflows are triggered in the central regions in short timescales.
Simulated galaxies without experiencing strong disturbances evolve
smoothly without modifying the metallicity gradients. Gas-rich systems
show large dispersion along the correlation. The dispersion in the
observed relation could be interpreted as produced by the combination of
galaxies with different gas-richness and/or experiencing different types
of interactions. Hence, our findings suggest that the observed relation
might be the smoking gun of galaxies forming in a hierarchical
clustering scenario.},
	journal = {ArXiv e-prints},
	author = {Sillero, Emanuel and Tissera, Patricia B. and Lambas, Diego G. and Michel-Dansac, Leo},
	month = sep,
	year = {2017},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {arXiv:1709.00438},
}

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