Revisitando o gradiente de abundâncias do disco da Via Láctea

Abstract

Planetary nebulae have been used extensively to study the chemical evolution of the Milky Way. They are originated by stars of medium and low mass (0.8 M⊙ to 8 M⊙) that have their outermost layers ejected, and the ejected material continues to be ionized by the white dwarf. There are countless works where the radial gradients of chemical abundances of the Milky Way were obtained from the NPs. Some works report that the oxygen gradient has deviations from a simple linear fit, but this gradient discontinuity is not a consensus in the literature. This apparent disagreement stems from the uncertainties involved in determining key quantities to obtain the gradient: chemical abundances and distances. In this work, we have a sample of 347 PNs with known chemical abundances, used for the construction of the radial abundance gradient of the Milky Way disk, from galactocentric distances obtained from the Gaia mission and statistical methods, where a physical property , like the diameter for example, is used to obtain the distances of the NPs, allowing a more accurate obtainment of the radial gradient of abundances of the Milky Way disk.