Year: 2024
Type: article
Abstract: High temporal resolution x-ray streak camera studies of micropinch formation in Cu hybrid x pinches reveal key plasma conditions. Analysis of Ne-like Cu lines indicate an average electron temperature of about 200 eV and 4.5×10^{28}m^{-3} electron density. The spectra suggest that the electron temperature jumps to about 1 keV, inferred from the continuum and the postcontinuum line emission that includes Li-like Cu lines. There is no sign of a rapid temperature change or a substantial surge in radiation emission during the 200 ps precontinuum x-ray burst, suggesting that the radiative collapse process does not play a major role in micropinch formation. Two-dimensional extended Magnetohydrodynamic (MHD) simulations, coupled to a collisional-radiative spectral analysis code, suggest the significance of the rapid radial implosion of high-temperature, low-density plasma, the axial outflow, and the dynamic plasma pressure in micropinch formation.
Source: Physical review. E
Authors: A. T. Elshafiey, N. G. Chalmers, D. A. Hammer
Institutions: Los Alamos National Laboratory, Cornell University
Language: English
Subfield: Control and Systems Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
Awards: G1017065088, G1279347439, X-RAY SPECTROSCOPIC STUDIES OF X-PINCH PLASMAS WITH 3-5 PICOSECOND RESOLUTION: A QUEST FOR CLEAR EXPERIMENTAL EVIDENCE FOR RADIATIVE COLLAPSE, CORNELL UNIVERSITY
PROJECT TITLE: X-RAY SPECTROSCOPIC STUDIES OF RADIATIVE COLLAPSE IN X-PINCH PLASMAS
THE CORNELL UNIVERSITY TEAM WILL CARRY OUT DENSE Z-PINCH EXPERIMENTS USING THE 400 KA XP PULSED POWER EXPERIMENTS BY PASSING THE CURRENT THROUGH A SHORT LENGTH OF WIRE THAT FIRST RESISTIVELY EXPLODES THE WIRE, AND THEN IMPLODES IT TO VERY HIGH DENSITY AND CAUSES IT TO PRODUCE A VERY SHORT (<0.1 NS) X-RAY BURST FROM A ~ 1 ΜM SOURCE CALLED A MICRO-PINCH. DIAGNOSTIC INSTRUMENTS WILL INCLUDE CRYSTAL SPECTROGRAPHS, X-RAY STREAK CAMERAS AND OTHER ELECTRICAL AND X-RAY DEVICES. THEY WILL CARRY OUT COMPUTER SIMULATIONS AND DETAILED ATOMIC PHYSICS CALCULATIONS TO ENABLE UNDERSTANDING OF THE X-RAY SPECTRA THAT ARE OBTAINED.
PROJECT OBJECTIVES
THE PRINCIPAL SCIENTIFIC OBJECTIVE OF THIS PROJECT IS TO DETERMINE IF THE PROCESS CALLED RADIATIVE COLLAPSE PLAYS A SIGNIFICANT ROLE IN THE FORMATION OF THE TINY, HOT, INTENSELY RADIATING DENSE PLASMA MICRO-PINCHES IN THE CURRENT-CARRYING PLASMA CONFIGURATION KNOWN AS AN X-PINCH. CORNELL WILL ADDRESS THIS QUESTION USING A COMBINATION OF HIGH TIME-RESOLUTION EXPERIMENTS USING A PULSED POWER MACHINE AND SEVERAL VERY HIGH TIME RESOLUTION X-RAY DIAGNOSTIC INSTRUMENTS, COMPUTER SIMULATIONS OF X-PINCH IMPLOSION DYNAMICS, AND DETAILED ATOMIC PHYSICS AND X-RAY SPECTROSCOPY CALCULATIONS. IF RADIATIVE COLLAPSE TAKES PLACE, THE RADIATION SPECTRUM AS A FUNCTION OF TIME SEEN ON THE X-RAY STREAK CAMERA WILL HAVE DIFFERENT CHARACTERISTICS THAN IF THE PLASMA IMPLOSION IS PURELY A RESULT OF HYDRO-MAGNETIC FLUID INSTABILITIES., G4056218910, CORNELL UNIVERSITY
''MULTI-UNIVERSITY CENTER OF EXCELLENCE FOR PULSED POWER-DRIVEN HIGH ENERGY DENSITY SCIENCE''
NEW AWARD PROVIDES INCREMENTAL FUNDING TO FULLY FUND BUDGET PERIOD 1 OF THE PROJECT PERIOD, G6410514744
OpenAlex ID: W4402860461