SIMBAD references

We analyze the 2"-resolution, high-sensitivity radio continuum observations of the nearby spiral galaxy NGC 6946 at 6 and 20 cm by Lacey, Duric, & Goss to derive a luminosity function at each wavelength for 43 H II region candidates and for 15 supernova remnant (SNR) candidates. The H II region radio luminosity functions are best fitted by power laws consistent with the shape of the optical luminosity function of Bonnarel, Boulsteix, & Marcelin. The SNR luminosity functions are fitted by considerably steeper power laws than the H II region luminosity functions. Extinctions to the H II regions are estimated from a comparison of radio flux densities with new optical fluxes derived from the Hα observations of Van Dyk. A dependence of extinction on galactocentric radius is investigated, but none is found.