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Download or read book Ultra-fast X-ray Thomson Scattering Measurements of Coalescing Shock-heated Matter written by and published by . This book was released on 2008 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment in this work was preformed at the Titan laser facility (S1) where a short pulse beam at a wavelength of 1053nm delivered up to 350J in 0.5 to 20 ps and a long pulse beam at 527nm, 2[omega] frequency provided energies up to 450J in 1 to 6 ns. Long pulse shaping in this experiment, similar to future capabilities at NIF, was primarily a 4ns long foot with an intensity of 1 x 1013 W/cm2, followed by a 2ns long peak with an intensity of 3 x 1013 W/cm2. A ≈ 600 um phase plate was used on the long pulse beam to moderate non-uniformities in the intensity profile. An illustration of the Thomson scattering setup for this experiment is provided in Fig. 1 of the main text. A nearly mono-energetic scattering source of [Delta]E/E ≈ 0.3% in the 4.5 keV Ti K-alpha line was produced via intense short-pulse laser irradiation of 1.9 x 3 x 0.01 mm Ti foils, creating energetic keV electrons in the process (S2, S3). The nearly isotropic source emission (S4) is produced in the cold solid density bulk of the foil from electron K shell ionization of neutral or weakly ionized atoms, with an emission size on the order of the laser focal spot. By optimizing the laser intensity and pulse width to 4.4 x 1016 W cm−2, a total of 2.3 x 1013 x-ray photons have been produced into 4[pi]. This value corresponds to a conversion efficiency of laser energy into Ti K-alpha x-ray energy of 5 x 10−5, see Fig. S1. These sources provide ≈10 ps x-ray pulses as measured experimentally (S5).