Informazioni sull’evento

02/09/2018

Astrophysics Talk

RR Lyrae stars in 2 nearby UFDs: Pisces II & Pegasus III

Alessia Garofalo (INAF - OAS Bologna)

Tuesday 25/05/2021 @ 14:00, Sala IV piano Battiferro

About 16 years ago the ultra-faint dwarfs (UFDs), the faintest dwarf galaxies, have been discovered around the Milky Way (MW). From that moment our understanding of their nature has rapidly improved. Photometric and spectroscopic follow-up observations of the UFDs stellar content are essential because distance, age and metallicity measurements will enable us to reconstruct their formation and evolution. Thanks to observations indeed we know that the UFDs are the most dark matter-dominated, oldest, most metal-poor and chemically primitive stellar systems known … but much work remains to be done, their census is incomplete, their origin is still matter of debate. I will present results from the study of variable stars and stellar populations hosted by Pisces II and Pegasus IIII UFD satellites of the MW. Using time series photometry collected with the Large Binocular Telescope we identify RR Lyrae stars which allowed us to measure the distance, trace the stellar population and derive main properties to compare with the properties of the MW stellar halo in order to get hints on the galactic formation process.