相关论文: Dormant dwarf spheroidal galaxies, deactivated by …
We present the star formation histories (SFHs) of early-type dwarf galaxies, dSphs and dEs, in the local universe within z=0.01. The SFHs of early-type dwarf galaxies are characterized by pre-enriched, metal-poor old stellar populations,…
Type Ia supernovae (SNe Ia) occur in both old, passive galaxies and active, star-forming galaxies. This fact, coupled with the strong dependence of SN Ia rate on star formation rate, suggests that SNe Ia form from stars with a wide range of…
By means of 3D hydrodynamic simulations, we study how Type Ia supernovae (SNe) explosions affect the star formation history and the chemical properties of second generation (SG) stars in globular clusters (GC). SG stars are assumed to form…
We present 3D hydrodynamical simulations aimed to study the dynamical and chemical evolution of the interstellar medium in dwarf spheroidal galaxies. This evolution is driven by the explosions of Type II and Type Ia supernovae, whose…
We present 3D hydrodynamic simulations aimed at studying the dynamical and chemical evolution of the interstellar medium in dwarf spheroidal galaxies. This evolution is driven by the explosions of Type II and Type Ia supernovae, whose…
Through 3D hydrodynamical simulations, we explore the impact of Type Ia supernova (SN) explosions on the star formation history and chemical properties of second-generation (SG) stars in young globular clusters with masses of 10^5-10^6…
Dwarf spheroidal satellite galaxies have emerged a powerful probe of small-scale dark matter clustering and of cosmic reionization. They exhibit structural and chemical continuity with dwarf irregular galaxies in the field and with…
Dwarf spheroidal (dSph) galaxies present an evolutionary puzzle that we explore in 40 early- and late-type dwarfs in the Local Group and nearby field. Although dSphs formed stars over extended periods, today all but one are free of…
Recent investigations on the delay time of type Ia supernovae have set useful constraints on the progenitors of type Ia supernovae. Here we have calculated the evolution of close binaries consisting of a white dwarf and a main-sequence or…
Using 3-dimensional hydrodynamical simulations of isolated dwarf spheroidal galaxies (dSphs), we undertake an analysis of the chemical properties of their inner regions, identifying the respective roles played by Type Ia (SNe Ia) and Type…
The suggestion that roughly half the mass of the galactic halo might be in the form of white dwarfs, together with the limits on the infrared background light and on the initial metallicity of the galactic disk, would set strong constraints…
We show that long-period dwarf novae offer a promising route for making Type Ia supernovae. For typical dwarf nova duty cycles d ~ 0.1 - 0.01, mass is accreted by the white dwarf mainly during dwarf nova outbursts at rates allowing steady…
We present a new model for the formation of stellar halos in dwarf galaxies. We demonstrate that the stars and star clusters that form naturally in the inner regions of dwarfs are expected to migrate from the gas rich, star forming centre…
The lack of hydrogen in spectra of type Ia supernovae (SN Ia) is often seen as troublesome for single-degenerate (SD) progenitor models. We argue that, since continued accretion of angular momentum can prevent explosion of the white dwarf,…
Dwarf galaxies in the Local Group appear to be stripped of their gas within 270 kpc of the host galaxy. Color-magnitude diagrams of these dwarfs, however, show clear evidence of episodic star formation (\Delta{}t ~ a few Gyr) over cosmic…
Using a population number synthesis code with detailed binary evolution, we calculate the distribution of the number of type Ia supernovae as a function of time after starburst. This is done for both main progenitor scenarios (single…
The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here we use a new observational technique to measure this time…
Recent extensive observations of Type Ia Supernovae (SNe Ia) have revealed the existence of a diversity of SNe Ia, including SNe Iax. We introduce two possible channels in the single degenerate scenario: 1) double detonations in…
(Abridged) Many dwarf galaxies exhibit sub-Solar metallicities, with some star-to-star variation, despite often containing multiple generations of stars. The total metal content in these systems is much less than expected from the heavy…
Although there is a nearly universal agreement that type Ia supernovae are associated with the thermonuclear disruption of a CO white dwarf, the exact nature of their progenitors is still unknown. The single degenerate scenario envisages a…