Peculiar Stars

Spectroscopic binaries, chromospheric emission, etc.

The GALAH survey: unresolved triple Sun-like stars discovered by the Gaia mission

The latest Gaia data release enables us to accurately identify stars that are more luminous than would be expected on the basis of their spectral type and distance. During an investigation of the 329 best Solar twin candidates uncovered among the spectra acquired by the GALAH survey, we identified 64 such over-luminous stars. In order to investigate their exact composition, we developed a data-driven methodology that can generate a synthetic photometric signature and spectrum of a single star.

Catalog of carbon enhanced stars and CEMP candidates

The Galactic Archaeology with HERMES (GALAH) survey is a large scale, magnitude limited, southern stellar spectroscopic survey providing spectra, stellar parameters and chemical abundances for stars located in different components of the Galaxy. Random selection, based only on object's brightness and its celestial coordinates, implies that a representative set of peculiar stellar types are observed.

Here we focus on carbon enhanced stars which can be identified by peculiar features present in their GALAH spectra.

Classification and diagnostics of the GALAH dataset with t-SNE reduction of spectral information

Peculiar spectra and objects to which they belong are relatively abundant among targets of general all-sky surveys such as GALAH. Detection of such objects is important because the automatic evaluation of their stellar and chemical properties might turn out to be very challenging and therefore introduces a complication in achieving scientific goals such as galactic archaeology.

Syndicate content