TiII in Milky way and Magellanic clouds

Comparisons of high-resolution [full width at half-maximum (FWHM)~1.3-1.5km/s] TiII spectra of Galactic targets with corresponding high-resolution spectra of NaI, KI and CaII reveal both similarities and differences in the detailed structure of the absorption-line profiles - reflecting component-to-component differences in the ionization and depletion behaviour of those species.

Moderate-resolution (FWHM~3.4-4.5km/s) spectra of more heavily reddened Galactic stars provide more extensive information on the titanium depletion in colder, denser clouds - where more than 99.9 per cent of the Ti may be in the dust phase. Moderate-resolution (FWHM~4.5-8.7km/s) spectra of stars in the Magellanic Clouds suggest that the titanium depletion is generally much less severe in the Large and Small Magellanic Clouds than in our Galaxy [for a given N(Htot), E(B-V), or molecular fraction f(H2)]- providing additional evidence for differences in depletion patterns in those two lower-metallicity galaxies.