... wind

The Bondi accretion rate does not vanish even if the thermal energy of the ISM is greater than the potential energy, due to the fresh gas provided by the stellar mass losses of the aging stars in the bulge.

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... nature

We recall that an element is secondary when it is produced starting from a seed non-primordial nucleus; therefore, its abundance is very sensitive on the metallicity of the gas where it is formed.

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...

We recall that, throughout this paper, we use the standard notation, i.e. for example [Fe/H] = $\log~($Fe/H$)-\log~($Fe/H$)_{\odot}$.

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