Estudo de nebulosas planetárias observadas com espectroscopia de campo integral

Abstract

In this work, four planetary nebulae (PNe) were studied through the analysis of integral field spectroscopy (IFS) data, obtained in one of the four telescopes that form the Very Large Telescope (VLT, European Southern Observatory, Chile). These objects were selected from an original sample of 16 observed PNe, based on the quality and completeness of the data necessary to determine their physical conditions and abundances. These four PNe had never been studied with IFS, a technique that allows obtaining spectral information spatially resolved. The origin of the diversity of PNe morphologies is not yet fully understood, being an important research front in this field. From this data we can investigate the morphological characteristics shown by the emission of different species and ions, in addition to physical and chemical parameters of these objects. Of the four PNe selected, He 2-108 was the focus of this work, as their observations showed several interesting characteristics. For this object, we made a detailed study, including the determination of line intensity maps and, from these, we determined gas temperature and density maps. Chemical abundances were calculated from the integrated spectrum, leading to an ADF(N/H) = 55. The analysis of the central region’s spectrum indicates that the central star still produces an intense wind that affects the emission of the most central region of the PN. The presence of that wind is an evidence of its very young evolutionary stage. The first results of the similar analysis made for the PNe He 2-117, He 2-434 and IC 4191 are also presented. The integrated spectra and the first flux maps of these objects were obtained