Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, Netherlands and the UK) and with participation of ISAS and NASA.

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CIA is a joint development by the ESA astrophysics division and the ISOCAM consortium.

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... absorption

For a typical visual absorption range of 1-3 mag, $f_{15~\mu\rm m}$ /H $\alpha$ varies between 10 and 80 (see Sauvage et al. 1996; Roussel et al. 2001).

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