Staged Z-pinch for Fusion Energy and a Neutron source
Institutskolloquium
- Datum: 05.12.2025
- Uhrzeit: 10:00 - 12:15
- Vortragender: Dr. Hafiz Rahman
- Dr. Hafiz Rahman is the President and Chief Scientist at Magneto-Inertial Fusion Technology Inc. (MIFTI) headquartered in Tustin, CA. Dr. Rahman was a faculty member in the University of California and retired 2012, from Department of Physics and Astronomy University of California Irvine. He has over four decades experience in the field of fusion energy and space physics research. His research spans on all three areas of experiment, theory, and computational physics. His particular emphasis on research has been on dense Z pinches for fusion energy, Field Reversed Configuration (FRC) laboratory simulation of space plasma structures, and propagation of neutralized plasma beams. Dr. Rahman invented the Staged Z-pinch (SZP) fusion concept, while working as principal investigator on SZP fusion which is based on magneto-inertial confinement involving a pinch-on-target process.
- Ort: IPP Garching
- Raum: Arnulf-Schlüter Lecture Hall in Building D2 and Zoom
- Gastgeber: IPP
- Kontakt: stefan.possanner@ipp.mpg.de
The gas-puff Staged Z-pinch (SZP) is a magneto-inertial fusion concept in which an annular liner of a high-Z material, such as Ar, Kr, or Xe implodes onto a column of target plasma of D or DT fuel. The success of this concept necessarily requires mitigation of instabilities like magneto-Rayleigh-Taylor (MRTI) instability, which develops on the surface of the imploding liner and can feed through the target disrupting the pinch. At peak implosion the pinch gets disrupted further by sausage and kink instabilities. Over the past several years this concept has been studied on 0.5 - 4.0 MA facilities using Ar and Kr gas puffs injected at R=1.2 and 2.5 cm. All these instabilities are mitigated quite effectively during implosion, particular in the larger radius pinch with the final pinch showing uniform implosion. Modeling with MACH2 and FLASH codes indicates that the larger radius allows stronger acceleration of the liner plasma and generation of shock waves that preheat a target plasma layer next to the liner to a temperatures Ti >1 keV. The resulting counter thermal pressure on the liner plasma limits the growth of the Magneto-Rayleigh-Taylor (MRT) instability at the liner-vacuum boundary and the implosion proceeds in a relatively stable manner. Near bang time the enormous target plasma thermal pressure smoothens the MRT perturbations developed during the earlier implosion stages. The recent experimental results from the 4 MA, 110 ns current rise time Double-EAGLE facility at L3Harris (currently, Fisica Inc.) where a larger radius nozzle created gas density profiles peaked at R=2. 5cm. Time integrated X-ray pinhole images with cutoff energy of 100 eV confirm that a long (~3cm), stable and uniform high energy density plasma column is formed in the final implosion stage. Consistent neutron yield in the 1010 - 1011 range was measured for both Ar and Kr liners imploding on a deuterium target. MHD simulations using MACH2 code show reasonable agreement with measured neutron yields from 0.5- 3-MA level. We are scheduled to reproduce these experiments at the new 7 MA Quad Eagle facility at Fisica Inc in early 2026. Simulations show favorable yield scaling to 12-MA machines, providing a path towards breakeven and beyond. As the footprint and wall-plug efficiency of such a high-current machine is important to consider, the use of linear transformer driver (LTD) technology to improve driver/load energy coupling, and compact switch assembly (CSA) technology to decrease driver size, will also be discussed as part of a conceptual design for future experiments.