Oxygen K-shell photoabsorption spectra of photoionized CO₂plasmas

Abstract

We report oxygen K-shell photoabsorption measurements in CO2 plasmas, using a table-top laser produced plasma soft x-ray (SXR) and extreme ultraviolet source. Significant differences are observed between the photoabsorption spectra of the neutral CO2 molecule and photoionized CO2 plasmas, as new spectral features emerge in the case of the latter. These features are attributed to photoexcitation in O, O+, O2+ species identified with the aid of calculations performed with the Cowan suite of atomic structure codes. Such signatures of atomic ions in the photoionized plasma point to the fragmentation of the parent molecule upon absorption of an SXR photon.

The 5d-6p VUV Photoabsorption Spectrum of Bi+

“…Analogous measurements yielding relative photoabsorption cross sections can be performed by means of table-top or laboratory scale techniques. One possibility is to perform photoabsorption measurements in atoms and the corresponding photoionized plasmas using radiation emitted from a laser produced plasma (LPP)-based source where a gas target serves as the active medium [14][15][16]. Another well-established method is the so-called dual laser plasma (DLP) technique [17,18].…”