A quantitative study of the 7.7 and 11.3 micron emission bands based on IRAS/LRS spectra

Annie Zavagno (1) , Pierre Cox (2, 1) , Jean-Paul Baluteau (1)

1 OAMP - Observatoire Astronomique de Marseille Provence
2 Max Planck Institute for Astrophysics

A quantitative analysis of the emission bands at 7.7 and 11.3 microns in the mid-IR spectra of HII regions, reflection nebulae, planetary nebulae, and galaxies is presented. The investigation is based on a sample of 113 sources whose spectra have been extracted from the IRAS/LRS data base. Relations of the intensity of the emission bands with physical conditions such as the excitation, and the relative contributions of emission bands and continuum around 10 microns to the mid-IR and FIR fluxes are presented and analyzed. A strong linear correlation is found between 7.7 and 11.3 micron band luminosities. The good correlation and the small dispersion (30 percent, compatible with the measurement errors) confirm, on a sample of sources, that the carriers of the 7.7 and 11.3 micron emission features belong to the same family, most likely aromatic molecular species such as PAH molecules.

Domaines: Astrophysique [astro-ph]

Annie Zavagno, Pierre Cox, Jean-Paul Baluteau. A quantitative study of the 7.7 and 11.3 micron emission bands based on IRAS/LRS spectra. Astronomy and Astrophysics - A&A, 1992, 259, pp.241-251. ⟨hal-02183808⟩