Structure of the outer Galactic disk

sobota 2020‐03‐07 12:00 – 12:30
  • Instituto de Astrofísica de Canarias
  • Fakulta matematiky, fyziky a informatiky, Univerzita Komenského v Bratislave

The structure of the outer disk of our Galaxy is still not well described and there are many features that need to be better understood. Gaia DR2 provides data in unprecedented quality that can be analyzed to shed some light on the outermost parts of the Milky Way. We calculated stellar density using star counts obtained from Gaia DR2, up to galactocentric distance R = 20 kpc using a deconvolution technique in the parallax errors. To recover star counts, we carry out the deconvolution, using the Lucy’s inversion method of the Fredholm integral equations of the first kind, without assuming any prior. We analyzed the density in order to study the structure of the outer Galactic disk and created density maps, where we can see structural features, mainly the warp. We studied the warp in greater detail, fitting it with multiple models and analyzing its properties. When we study the northern and the southern warps separately, we get an asymmetry of ~25 % larger amplitude in the north. We also study the flare – the increase of the scaleheight with galactocentric distance. We will show preliminary results of our analysis,