Open AccessNear‐infrared [Fe ii ] emission from supernova remnants and the supernova rate of starburst galaxies
Author(s) -
Morel T.,
Doyon R.,
StLouis N.
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05026.x
Subject(s) - physics , astrophysics , supernova , galaxy , metallicity , luminosity , interstellar medium , luminous infrared galaxy , radiative transfer , infrared , astronomy , line (geometry) , geometry , mathematics , quantum mechanics
In an effort better to calibrate the supernova rate of starburst galaxies as determined from near‐infrared [Fe ii ] features, we report on a [Fe ii ] λ 1.644 μm line‐imaging survey of a sample of 42 optically selected supernova remnants (SNRs) in M33. A wide range of [Fe ii ] luminosities are observed within our sample (from less than 6 to 695 L ⊙ ). Our data suggest that the bright [Fe ii ] SNRs are entering the radiative phase and that the density of the local interstellar medium (ISM) largely controls the amount of [Fe ii ] emission. We derive the following relation between the [Fe ii ] λ 1.644 μm line luminosity of radiative SNRs and the electronic density of the post‐shock gas, n e : L [Fe ii ] (cm −3 ). We also find a correlation in our data between L [Fe ii ] and the metallicity of the shock‐heated gas, but the physical interpretation of this result remains inconclusive, as our data also show a correlation between the metallicity and n e . The dramatically higher level of [Fe ii ] emission from SNRs in the central regions of starburst galaxies is most likely due to their dense environments, although metallicity effects might also be important. The typical [Fe ii ]‐emitting lifetime of a SNR in the central regions of starburst galaxies is found to be of the order of 10 4 yr. On the basis of these results, we provide a new empirical relation allowing the determination of the current supernova rate of starburst galaxies from their integrated near‐infrared [Fe ii ] luminosity.