Laser-plasma sources

From an experimental viewpoint, Thomson scattering has been recently observed by using electron beams from a LIN AC [91] as well as from a laser-plasma source based on LWFA [92]. This latter observation, in particular, allows the availability of table-top, tunable sources of X/7-rays to be foreseen. 

First, we consider the situation where the coherence time, i.e., the time during which Cp(t) is substantially different from zero, is so short (sub-fs) that we can ignore all of the dynamics in the material system during this time. This is a relevant limit for X-rays from incoherent synchrotron radiation and laser plasma sources [4]. The time-dependent material system is created by the pump UV-laser pulse and it, therefore, contains amplitude on the electronic ground state as well as on one (or several) excited electronic state(s). Adopting a density-operator description, we expand the state of the material system in the adiabatic electronic basis,... 

Jin F, Richardson M (1995) New laser plasma source for extreme-ultraviolet lithography. Appl Opt 34 5750-5760... 

L. Malmqvist, L. Rymell, H.M. Hertz Droplet-target laser-plasma source for proximity X-ray lithography. Appl. Phys. Lett. 68, 2627 (1996)... 

The so-called superbenzene, coronene, was used as a substrate by Pozniak and Dunbar (1997) in an FTICR-MS study of the formation kinetics of monomer and dimer association complexes with Sc and Y, together with several other main-group and transition metal cations. The formation of coronene adducts was also observed for RO" " and R(OH)2 ions, for both Sc and Y, with rates similar to the attachment rates for the corresponding bare metal ions the same ions were produced by the reaction of R(coronene) with background oxygen/water. In a different approach, Duncan and coworkers used covaporization of Nd oxide and pyrene in a laser plasma source with time-of-flight mass spectrometry (TOF-MS) detection to produce NdO(pyrene) " ions, with =1, 2 (Ayers et al., 2004). 

Srzic and coworkers (Kazazic et al., 2005, 2006 Srzic et al., 1997a,b) reported qualitative studies of reactions of U with polyaromatic hydrocarbons (PAHs). The results were complicated by competition between oxidation and adduct formation, but an intriguing observation was the addition of multiple PAH molecules to U, such as in [U(phenanthrene)3] dehydrogenation of PAHs was also observed. Duncan and coworkers also examined the formation of uranium cationic complexes with PAHs using covaporization of uranyl acetate and pyrene (Ayers et al., 2004) or corannulene (Ayers et al., 2005) in a laser plasma source with TOF-MS detection, observing the formation of UO (PAH) species with x=0-2 and y=l, 2. 

The development of mote intense sources (eg, plasma sources, soft x-ray lasers, and synchrotron sources) has made possible highly effective instmments both for x-ray microscopy and x-ray diffraction on a few cubic nanometer sample. The optical problem of focusing x-rays is accompHshed by the use of zone plates or by improved grazing incidence or multilayer reflectors. 

Figure 6. Schematic outline of the first commercially available multiple collector ICPMS, the Plasma 54, after Halhday et al. (1995). This instrument uses Nier-Johnson double-focusing and is equipped with eight independently adjustable Faraday collectors. The axial collector can be wound down to provide access to a Daly detector equipped with ion counting capabilities and a second-stage energy filter for high abundance sensitivity measurements. The sample may be introduced to the plasma source by either solution aspiration or laser ablation.

Gray AL (1985). Solid sample introduction by laser ablation for inductively coupled plasma source mass spectrometry. Analyst 110 551-556... 

Fig. 3.1. Left visible pump/X-ray probe scheme for femtosecond TRXRD experiments. Hard X-ray pulses are generated by shining intense femtosecond laser pulses on a metal target (laser plasma X-ray source). Right geometrical structure factor of bismuth as a function of inter-atomic distance for diffraction from (111) and (222) lattice planes. From [1] and [2]...

Laser Plasma Acceleration and Related Electromagnetic Sources... 

Ultrashort laser-plasma X-ray sources based upon the Ka emission process have been exploited since about 10 years ago to study some dynamical effects in simple systems, typically involving atomic motion, occurring on the timescale of 100fs. A complete review of such effects, in particular in... 

The overwhelming development of the ultrashort and ultraintense laser systems based on the CPA technique enables to foresee a clear way to get miniaturized (table-top) particle accelerators and related sources of X/7-rays. Such a reduction in dimensions and costs has made realistic the application of these innovative apparatus to several fields, from medical diagnostics and therapy to material science and femto-chemistry. Furthermore, particles accelerated by laser-plasma interaction can be used in the fast-ignition approach... 

Laser-induced plasma spectroscopy (LIPS), archaeological materials, 5 743 Laser isotope separation, 25 416 417 Laser light, 14 655-656 Laser light sources, in photochemical technology, 19 107-108... 

With the advent of multiple-collector inductively coupled plasma-source mass spectrometry (MC-ICPMS) it is now possible to measure Mg/ Mg and Mg/ Mg of Mg in solution with a reproducibility of 30 to 60 ppm or better (Galy et al. 2001). What is more, ultraviolet (UV) laser ablation combined with MC-ICPMS permits in situ analysis of Mg-bearing mineral samples with reproducibility of 100 to 200 ppm (Yoimg et al. 2002a). These new analytical capabilities allow mass-dependent fractionations of the isotopes of Mg to be used as tracers in natural systems. 

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