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Star formation in the outer regions of the early-type galaxy NGC 4203

Composite g′ + r′ MegaCam image of NGC 4203 with the dust lanes superimposed in red (Yildiz et al.2015)

NGC 4203 is a nearby early-type galaxy surrounded by a very large, low-column-density H I disc. In this paper, we study the star formation efficiency in the gas disc of NGC 4203 by using the UV, deep optical imaging and infrared data.

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Applying galactic archeology to massive galaxies using deep imaging surveys

Collection of images from the MATLAS survey for a sample of ETGs (IAUS311)

Various programs aimed at exploring the still largely unknown low surface brightness Universe with deep imaging optical surveys have recently started. They open a new window for studies of galaxy evolution, pushing the technique of galactic archeology outside the Local Group (LG).

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The stellar accretion origin of stellar population gradients in massive galaxies at large radii

Colour gradients (g − i, g − r and u − g, from left to right) at z = 2, 1, 0 (from top to bottom) for the 10 galaxies (different colours) in the MNoW and WM models (Hirschmann et al., 2015)

We investigate the evolution of stellar population gradients from z = 2 to 0 in massive galaxies at large radii (r > 2Reff) using 10 cosmological zoom simulations of haloes with 6 × 1012 M⊙ < Mhalo < 2 × 1013 M⊙. The simulations follow metal cooling and enrichment from SNII, SNIa and asymptotic giant branch winds. We explore the differential impact of an empirical model for galactic winds that reproduces the mass-metallicity relation and its evolution with redshift.

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