Conveners
Galactic Chemical Evolution
- Alessandro Chieffi (Istituto Nazionale di Fisica Nucleare)
Galactic Chemical Evolution
- Alessandro Chieffi (Istituto Nazionale di Fisica Nucleare)
The modelling of the chemical evolution and nucleosynhesis in galaxies is depending on a number of uncertainties, concerning stellar evolution with mixing in stars, stellar mass loss, galactic evolution with star-formation rates, mixing of populations, infall of pristine gas, etc.
These uncertainties are often handled by introducing free parameters which are varied in order to fit...
Spectroscopic observations of stars belonging to open clusters, with well-determined ages and distances, are a unique tool for constraining stellar evolution, nucleosynthesis, mixing processes, and ultimately galactic chemical evolution. Abundances of slow (s) process neutron capture elements in stars that retain their initial surface composition open a window into the processes that generated...
In the era of Gaia and large spectroscopic surveys, an important missing ingredient to complete the Galactic archaeology is provided by stellar ages. A powerful method to infer precise age for field giant stars is obtained exploiting asteroseismic datasets collected by space missions such as Kepler/K2 and TESS. Thanks to these unprecedented constraints from asteroseismology, we can explore the...
The s-process nucleosynthesis in asymptotic giant branch stars impacts the enrichment of heavy elements. However, since Truran 1981, we know that the entire picture comprehends other actors, such as r-process events.
The electromagnetic counterpart of GW170817 has shown that neutron star mergers host an r-process production of neutron-capture elements, but are neutron star mergers the only...
Galactic feedback driven by massive stars and active galactic nuclei (AGNs) plays a fundamental role in regulating galaxy evolution. Galaxies are filled with chemical elements and dust, released in their interstellar medium through different channels, e.g., supernova explosions, stellar winds. However, intense starburst episodes could generate strong outflows able to suppress star formation...
The outflows of AGB stars are rich astrochemical laboratories, with close to a 100 chemical species and some 15 newly formed dust grains detected so far. They host interesting and unique chemical regimes thanks to the large gradients in temperature and density throughout the outflow. Moreover, chemistry and dynamics are closely linked throughout the outflow, making the study of molecules...
Massive stars are among the most-significant drivers of stellar feedback and chemical evolution, due to their short evolutionary time scale. Occurring typically in groups, their nucleosynthesis ashes are distributed in an interstellar surroundings that has been shaped by massive-star feedback. We will discuss what 26Al gamma-ray observations and related studies have taught us, and which...
We present here the results of high resolution (M_gas= 2.4x10^4 M_sun) Galactic Chemical Evolution (GCE) models of Milky-Way type galaxies. We restrict ourselves to "monolithic" models where the galaxy forms and evolves in isolation, i.e. we do not include any mergers nor tidal fields from neighboring galaxies. All our models start from redshift z=8 and we assume a flat CDM cosmology...
