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We study the star formation history of normal spirals by using a large and homogeneous data sample of local galaxies. For our analysis we utilise detailed models of chemical and spectrophotometric galactic evolution, calibrated on the Milky Way disc. We find that star formation efficiency is independent of galactic mass, while massive discs have, on average, lower gas fractions and are redder than their low mass counterparts; put together, these findings convincingly suggest that massive spirals are older than low mass ones. We evaluate the effective ages of the galaxies of our sample and we find that massive spirals must be several Gyr older than low mass ones. We also show that these galaxies (having rotational velocities in the 80-400 km/s range) cannot have suffered extensive mass losses, i.e. they cannot have lost during their lifetime an amount of mass much larger than their current content of gas+stars.
We study the chemical and spectro-photometric evolution of galactic disks with detailed models calibrated on the Milky Way and using simple scaling relations, based on currently popular semi-analytic models of galaxy formation. We compare our results
We explore the implications for the high redshift universe of ``state-of-the-art models for the chemical and spectrophotometric evolution of spiral galaxies. The models are based on simple ``scaling relations for discs, obtained in the framework of C
The problem of chemo-photometric evolution of late-type galaxies is dealt with relying on prime physical arguments of energetic self-consistency between chemical enhancement of galaxy mass, through nuclear processing inside stars, and luminosity evol
We investigate the formation and evolution of giant molecular clouds (GMCs) by the collision of convergent warm neutral medium (WNM) streams in the interstellar medium, in the presence of magnetic fields and ambipolar diffusion (AD), focusing on the
Chemo-dynamical N-body simulations are an essential tool for understanding the formation and evolution of galaxies. As the number of observationally determined stellar abundances continues to climb, these simulations are able to provide new constrain