The chemical abundances in a sample of dwarf irregular galaxies. II. The case of IC 4662 and ESO 245-G05

Optical spectra of H II regions of two dwarf irregular galaxies are presented. The objects are IC 4662 and ESO 245-G05. Chemical abundances were derived in all the H II regions where the forbidden oxygen line [OIII]λ4363 Å was detected. For spectra with the highest quality, a study of the spatial distribution of chemical elements in these objects were made. Generally, the chemical composition is largely constant within the H II regions studied. Some differences are found but could be attributed varying physical properties, e.g. small scale fluctuations in the temperature of the region. A comparison of the chemical abundances between different H II regions within the galaxies is made for IC 4662 and ESO 245-G05, where one of the H II regions clearly shows deviating chemical abundances.