학술논문

Spectroscopic measurements in the post-hole convolute on Sandia's Z-Machine (invited)
Document Type
Conference
Source
2011 IEEE Pulsed Power Conference Pulsed Power Conference (PPC), 2011 IEEE. :688-695 Jun, 2011
Subject
Power, Energy and Industry Applications
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Components, Circuits, Devices and Systems
Computing and Processing
Communication, Networking and Broadcast Technologies
Signal Processing and Analysis
Probes
Plasma measurements
Optical fiber testing
Magnetic noise
Displacement measurement
Electric shock
Magnetic shielding
Language
ISSN
2158-4915
2158-4923
Abstract
Pulsed power is a key driver for high energy density (HED) science. The Z-Machine is the world's largest pulsed power driver, and as such is one of the foremost platforms for HED science. The double post-hole convolute current adder is a critical element in low impedance, multi-module pulsed power device design. Post-refurbishment, the current loss in the convolute has reached as high as 5 MA (20% of the MITL current). Measurements of the plasma forming in this region will lead to a better understanding of the losses, and may help with a redesign of the system. Spectroscopic measurements of the convolute show strong continuum emission with absorption features. Most notably we observe the hydrogen H-alpha at 6563 Å. Lithium was introduced into the convolute as a tracer; this experiment put upper and lower bounds on the axial position of the observed continuum emitter, (located in the upper post-hole). Measurements of the location of continuum emission as a function of time indicate that plasma travels from cathode to anode with an apparent velocity of greater than 7 cm/μs.