|
HII regions are not simple objects. Turbulent flows that may be supersonic, Herbig-Haro jets often crisscross sections of the nebula, stellar winds from the massive stars are some of the processes at work. A particular observation has been nagging astrophysicists for some 70 years, called the abundance discrepancy problem (ADP). Essentially, the abundance measured from collisionnally excited lines is quite different from the one measured via recombination lines. Factors from 3-5 were measured, it is even worst for planetary nebulae. A number of physical processes have been proposed but none reproduce the observations. We proposed a new systematic approach using the SITELLE Fourier transform spectrometer at the Canada-France-Hawaii Telescope and Fabry-Perot observations from the Observatoire du mont Megantic and Observatoire de Haute-Provence. We targeted the HII region Sh2-158 and a section of the Orion nebula. I will discuss mainly the CFHT results from Sh2-158 |
|