Related papers: The Upper Initial Mass Function from Ultraviolet S…
Feedback from massive stars is believed to play a critical role in driving galactic super-winds that enrich the IGM and shape the galaxy mass function and mass-metallicity relation. In previous papers, we introduced new numerical methods…
A significant step forward in the understanding of Planetary Nebula (PN) formation can be achieved by exploring the connection of PN with stellar evolution. In particular, the initial mass of the star plays a crucial role, as it determines…
A remarkable span of frontier astrophysics, from gravitational-wave archaeology to the origin of the elements to interpreting snapshots of the earliest galaxies, depends sensitively on our understanding of massive star formation and…
We consider the hypothesis that the formation of elliptical galaxies includes a phase in which star formation is mostly restricted to massive stars, with the bias towards high mass stars increasing with elliptical galaxy mass. The mass…
Extreme helium stars are very rare low-mass supergiants in a late stage of evolution. They are probably contracting to become white dwarfs following a violent phase of evolution which caused them to become hydrogen-deficient giants,…
The absence of direct high redshift observations poses a significant challenge in understanding the properties of first stars. Nonetheless, the cumulative effect of entire stellar populations can be studied with current data. In this work…
The local stellar mass density is observed to be significantly lower than the value obtained from integrating the cosmic star formation history (SFH), assuming that all the stars formed with a Salpeter initial mass function (IMF). Even…
The stellar initial mass function (IMF) is predicted to depend upon the temperature of gas in star-forming molecular clouds. The introduction of an additional parameter, $T_{IMF}$ , into photometric template fitting, allows galaxies to be…
The stellar initial mass function (IMF) describes the distribution of stellar masses that form in a given star formation event. The long main-sequence lifetimes of low-mass stars mean that the IMF in this regime (below $\sim 1…
Nearby dwarf galaxies provide a unique laboratory in which to test stellar population models below $Z_\odot/2$. Such tests are particularly important for interpreting the surprising high-ionization UV line emission detected at $z>6$ in…
The stellar initial mas function (IMF) has been described as being invariant, bottom heavy or top-heavy in extremely dense star burst conditions. To provide usable observable diagnostic we calculate redshift dependent spectral energy…
As sources of chemical enrichment, ionizing radiation and energetic feedback, massive stars drive the ecology of their host galaxies despite their relative rarity, additionally to yielding compact remnants, which can generate gravitational…
Within the birth environment of a massive globular cluster, the combination of a luminous young stellar population and a high column density induces a state in which the thermal optical depth and radiation pressure are both appreciable. In…
The medium around massive stars is strongly shaped by the stellar winds. Those winds depend on various stellar parameters (effective temperature, luminosity, chemical composition, rotation, ...), which are varying as a function of the time.…
We report the stellar mass functions obtained from 20 radiation hydrodynamical simulations of star cluster formation in 500 M$_\odot$ molecular clouds with metallicities of 3, 1, 1/10 and 1/100 of the solar value, with the clouds subjected…
We perform a spectroscopic study to constrain the stellar Initial Mass Function (IMF) by using a large sample of 24,781 early-type galaxies from the SDSS-based SPIDER survey. Clear evidence is found of a trend between IMF and central…
The most massive stars are thought to lose a significant fraction of their mass in a steady wind during the main-sequence and blue supergiant phases. This in turn sets the stage for their further evolution and eventual supernova, with…
We discuss the uncertainties and the systematic effects that exist in the estimates of the stellar masses of high redshift galaxies, using broad band photometry, and how they affect the deduced galaxy stellar mass function. We use at this…
Our current understanding of the star formation histories of early-type galaxies is reviewed, in the context of recent observational studies of their ultra-violet (UV) properties. Combination of UV and optical spectro-photometric data…
The Initial Mass Function (IMF) of early-type galaxies (ETGs) has been found to feature systematic variations by both dynamical and spectroscopic studies. In particular, spectral line strengths, based on gravity-sensitive features, suggest…