• De Groot, F.
• Waters, L.
• Mutschke, H.
• De Vries, C.
• Costantini, Elisa
• Zeegers, S. T.
• Pinto, Ciro

Abstract

X-ray spectroscopy of interstellar dust (ID), seen in absorption against spectra of bright back- ground sources, is a powerful tool to investigate and provide novel information on the chemistry of dust grains. For example, sharp and deep absorption features of Mg, Si, O and Fe, which are the building blocks of silicates, fall in the X-ray band. Therefore X-ray spectroscopy can also successfully study the nature of the iron inclusion in dust. The shift and the structure of a given absorption feature is indeed different for different absorbing dust grains. High-quality data have already revealed that Mg-rich silicates are favored with respect to the Fe-rich population and that Fe is most likely in metallic form. The modeling of spectra of present and future X-ray facili- ties will take now advantage of our new laboratory measurements, from several species, of the absorption features which are key for a complete understanding of the ID chemistry....

Topics

• impedance spectroscopy
• grain
• inclusion
• iron
• X-ray spectroscopy