X-ray absorption in the ISM
The Interstellar Medium (ISM), gas and dust between stars, is an important component in the stellar formation and stellar evolution processes. I have studied this environment in detail through the high-resolution X-ray spectroscopy. Using
Chandra and
XMM-Newton X-ray spectra, I measured reliable values of its abundance, column densities, and ionization fractions, finding that the predominant component of the ISM is the neutral gas (~ 90%).
I developed a new X-ray absorption model called
ISMabs that takes into account both neutral and ionized species from H, He, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni and Zn. This model is provided in the appropriate format to be implemented in widely used X-ray spectral fitting packages such as
XSPEC, ISIS, and
Sherpa.