we wish to determine the emission line ratios of infrared lines important in the cooling of metal-rich giant hii regions in the nearby spiral galaxies m83 and m51. these line ratios, which only iso has the capability to measure in the near future, will allow us to fit detailed theoretical models of the hii regions, and: (i) determine, for the first time, accurate chemical abundances in the gas at metallicities higher than solar, (ii) very greatly improve the calibration of the important optical strong line abundance indicator for giant hii regions at high metallicities, with considerable benefit to the whole field of chemical abundances and chemical evolution in galaxies, (iii) investigate the extent of depletion of the refractory elements si and fe onto grains in giant hii regions, and the relative importance of infrared emission lines of si and fe as coolants in metal-rich nebulae.
Instrument
LWS01 , SWS01
Temporal Coverage
1996-06-06T13:26:27Z/1997-02-07T11:00:43Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, EDMUNDS et al., 1999, 'THE COOLING AND COMPOSITION OF EXTRAGALACTIC HII REGIONS', 1.0, European Space Agency, https://doi.org/10.5270/esa-gu15xfs
