Solar Metallicity in M82 Starburst with Far-Infrared Spectroscopy

The starburst galaxy M82 has been frequently studied due to its high star formation rate as well as its closeness to the Milky Way. Though observation for M82 have been popular there has not been any indication that a measure of metallicity has been accurate. Utilizing far-infrared(far-IR) structure lines for [OIII] 52 and 88um and [NIII] 57um taken from SOFIA/FIFI-LS and PACS/Herschel we applied a known ratio between these far-IR lines and from this find that the solar metallicity in the ionized gas of the central starburst region of M82 is ~3x higher than previous X-ray estimates. We also see that our method is robust against the very high dust obscuration in the starburst.