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We use the most extensive integral field spectroscopic map of a local galaxy, NGC 628, combined with gas and stellar mass surface density maps, to study the distribution of metals in this galaxy out to 3 effective radii ($rm R_e$). At each galactocentric distance, we compute the metal budget and thus constrain the mass of metals lost. We find that in the disc about 50% of the metals have been lost throughout the lifetime of the galaxy. The fraction of metals lost is higher in the bulge ($sim$70%) and decreases towards the outer disc ($rm sim 3 R_e$). In contrast to studies based on the gas kinematics, which are only sensitive to ongoing outflow events, our metal budget analysis enables us to infer the average outflow rate during the galaxy lifetime. By using simple physically motivated models of chemical evolution we can fit the observed metal budget at most radii with an average outflow loading factor of order unity, thus clearly demonstrating the importance of outflows in the evolution of disc galaxies of this mass range ($rm log(M_star/M_odot) sim 10)$. The observed gas phase metallicity is higher than expected from the metal budget and suggests late-time accretion of enriched gas, likely raining onto the disc from the metal-enriched halo.
We now have mounting evidences that the circumgalactic medium (CGM) of galaxies is polluted with metals processed through stars. The fate of these metals is however still an open question and several findings indicate that they remain poorly mixed. A
The total specific angular momentum j of a galaxy disk is matched with that of its dark matter halo, but the distributions are different, in that there is a lack of both low- and high-j baryons with respect to the CDM predictions. I illustrate how th
The most distant galaxies known are at z~10-11, observed 400-500 Myr after the Big Bang. The few z~10-11 candidates discovered to date have been exceptionally small- barely resolved, if at all, by the Hubble Space Telescope. Here we present the disco
We present infrared (IR) spectral energy distributions (SEDs) of individual star-forming regions in four extremely metal poor (EMP) galaxies with metallicity Z around Zsun/10 as observed by the Herschel Space Observatory. With the good wavelength cov
We present the results of CO(1-0) observations of the host galaxy of a Type I superluminous supernova (SLSN-I), SN2017egm, one of the closest SLSNe-I at z = 0.03063, by using the Atacama Large Millimeter/submillimeter Array. The molecular gas mass of