Enhancement of x-ray yield from the Z-Beamlet laser for monochromatic backlighting by using a prepulse
- Sandia National Laboratories, PO Box 5800, Albuquerque, New Mexico 87185-1193 (United States)
The Z-Beamlet Laser (ZBL) is capable of providing on-target energies of up to 1.5 kJ at 527 nm in up to four separate 0.3-1.5 ns pulses during a 20 ns window. ZBL is routinely used as a source of x rays for backlighting experiments on the Sandia Z facility, a 20 MA, 100 ns rise-time, pulsed-power driver for z-pinch plasma radiation sources. Most backlighting experiments use monochromatic crystal imaging diagnostics at 1865 or 6151 eV. We present calibration data demonstrating that the use of a 0.3-0.6 ns, {approx}200 J pulse, followed 2 ns later by a 1.0 ns, {approx}1 kJ pulse results in more than twice the x-ray yield at 6151 eV (a He-like Mn emission line) compared to a single 1.0 ns, {approx}1 kJ pulse. The first pulse creates a plasma (and few x rays) that expands and approaches the critical density for the laser when the second pulse arrives, creating a more efficient coupling of laser light to the plasma. A similar improvement was also noted for He-like Ni emission lines, suggesting that this simple technique scales to higher photon energies.
- OSTI ID:
- 20861189
- Journal Information:
- Review of Scientific Instruments, Vol. 77, Issue 10; Other Information: DOI: 10.1063/1.2228515; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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