Fast Framing Camera Images of Neutron Production at High Currents in Dense Plasma Focus Machines Framing Camera Images courtesy of Specialised Imaging University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Robert O'Brien 1, Daniel Lowe 1, Tim Meehan 2, Chris Hagen 2 1 University of Nevada, Las Vegas, Las Vegas, NV, United States 2 NSTec, North Las Vegas, NV, United States DOE/NV/ This work was done by National Security Technologies, LLC, under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy.

Dense Plasma Focus (DPF) at NSTec in Las Vegas, NV Mather style Anode/Cathode D-D operation in Las Vegas up to 1x10 12 neutrons per shot 35kV Operations for Data Presented ~2MA Current University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

DPF Configuration for Imaging University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Pinch Point

MHD Simulation of DPF Operation University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Experimental Goal Obtain images of pinch before, during and after neutron production Acquire images of complete plasma rundown Analyze differences between a neutron yielding pinch and a pinch at higher “turn off” current where neutron yield ceases University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Camera and Line of Sight to DPF University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Lead shield for gamma flash Mirrors DPF Window

Camera and Line of Sight to DPF University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 TOF Detectors DPF Window

Experimental Setup Images correlated to neutron/photon TOF data are for a detector at 28.5meters from the pinch Corresponds to ~1280ns of travel time between neutron creation and arrival at detector University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

MCNPX Neutron/Gamma Movie University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Phantom Camera Images Ametek Phantom v711 Images here 32x128 Resolution Frame Rate: 680,000 fps (1.47us / frame) University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Fast Framing Camera Images Images from 3 DPF shots correlated to Neutron and Photon TOF data Intervals between images range from 200ns to 17ns Exposure times from 10ns to 4ns 1280x960 Resolution 16 frames total University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Fast Framing Camera - DPF Shot ns interval between frames University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

First photon peak, Frame 6 Second photon peak, Frame 7 Neutron Arrival 2.5 MeV neutrons at 45 ns/m at 28.5 m = 1282 ns arrival time. Distance between arrows = 1285 ns University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Arrival Time (us) DPF Shot 4 TOF Data – Image Interval 200ns – Exposure 10ns Neutron Yield = 1x MA Current 6.40us Rundown Camera Triggers

Shot 4 Movie – Neutron production between Frames 5 and 6? University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 DPF Shot 4– Image Interval 200ns – Exposure 10ns Neutron Yield = 1x MA Current 6.40us Rundown Images courtesy of Specialised Imaging

Shot 4 Movie – Neutron production between Frames 5 and 6? University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 DPF Shot 4– Image Interval 200ns – Exposure 10ns Neutron Yield = 1x MA Current 6.40us Rundown Images courtesy of Specialised Imaging

Frame 6Frame 7 University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Shot 4 – Frames 6 and 7 Images courtesy of Specialised Imaging

Corresponding Shot 4 Phantom Camera Movie University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 DPF Shot 4 Image Interval 1.47us Exposure 1.09us Neutron Yield = 1x MA Current 6.40us Rundown

Fast Framing Camera - DPF Shot 5 75 ns interval between frames University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

First photon peak Second photon peak Neutrons 2.5 MeV neutrons at 45 ns/m at 28.5 m = 1282 ns arrival time. Distance between arrows = 1287 ns University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 DPF Shot 5 TOF Data – Image Interval 75ns – Exposure 5ns Neutron Yield = 9x MA Current 6.42us Rundown Arrival Time (us)

Frame 5 University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

Shot 5 - Movie DPF Shot 5 – Image Interval 75ns – Exposure 5ns Neutron Yield = 9x MA Current 6.42us Rundown Images courtesy of Specialised Imaging

Frame 5 University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Shot 5 - Frame 5 DPF Shot 5 – Image Interval 75ns – Exposure 5ns Neutron Yield = 9x MA Current 6.42us Rundown Images courtesy of Specialised Imaging

Corresponding Shot 5 Phantom Camera Movie University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 DPF Shot 5 Image Interval 1.47us Exposure 1.09us Neutron Yield = 9x MA Current 6.42us Rundown

Fast Framing Camera - DPF Shot ns interval between frames University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013

First photon peak Second photon peak Neutrons 2.5 MeV neutrons at 45 ns/m at 28.5 m = 1282 ns arrival time. Distance between arrows = 1281 ns University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Arrival Time (us) DPF Shot 10 TOF Data – Image Interval 17ns – Exposure 4ns Neutron Yield = 6x MA Current 6.30us Rundown

University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Arrival Time (us) Camera Triggers DPF Shot 10 TOF Data – Image Interval 17ns – Exposure 4ns Neutron Yield = 6x MA Current 6.30us Rundown First photon peak arrival

Frame 1Frame 2Frame 3 Frame 4Frame 5Frame 6 Frame 7Frame 8 University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013 Images courtesy of Specialised Imaging

Conclusions Demonstrated ability to capture quality, high speed images of pinch point Timing is a major challenge to imaging the pinch during neutron creation Pinch does not occur at a completely fixed repeatable time from shot to shot Next step is capture pinch images at higher, “turn off” currents for diagnostic analysis University of Nevada, Las Vegas - National Security Technologies, LLC - IEEE PPPS 2013