We present a proof of principle experiment on single-shot near edge soft X-ray fine structure (NEXAFS) spectroscopy with the use of a laboratory laser-plasma light source. The source is based on a plasma created as a result of the interaction of a nanosecond laser pulse with a double stream gas puff target. The laser-plasma source was optimized for efficient soft X-ray (SXR) emission from the krypton/helium target in the wavelength range from 2 nm to 5 nm. This emission was used to acquire simultaneously emission and absorption spectra of soft X-ray light from the source and from the investigated sample using a grazing incidence grating spectrometer. NEXAFS measurements in a transmission mode revealed the spectral features near the carbon K-α absorption edge of thin polyethylene terephthalate (PET) film and L-ascorbic acid in a single-shot. From these features, the composition of the PET sample was successfully obtained. The NEXAFS spectrum of the L-ascorbic acid obtained in a single-shot exposure was also compared to the spectrum obtained a multi-shot exposure and to numerical simulations showing good agreement. In the paper, the detailed information about the source, the spectroscopy system, the absorption spectra measurements and the results of the studies are presented and discussed.
A high brightness laser-plasma X-ray source has
been set-up and is presently available at IFAM. A wide
range of diagnostics has been set up to monitor the properties
of the X-ray radiation and to control the main parameters
including photon energy, flux intensity, and pulse duration.
A beam extractor enables access to the X-ray radiation
at atmospheric pressure. A simple, easy-to-use projection
microscope has been built which is capable of single-shot
micron resolution imaging with digital acquisition. Preliminary
biomedical experiments show that the X-ray doses available
on a single laser shot exposure of our source fully meet
the conditions required for an important class of biological
experiments based on X-ray induced DNA damage providing
an ideal alternative to the long time exposures needed
with X-ray tubes.
Low-emittance electron bunches from a laser-plasma accelerator measured using single-shot X-ray spectroscopy