$Z$ -Pinch Interferometry Analysis With the Fourier-Based TNT Code

We present the analysis of interferometry diagnostics with the user-friendly Talbot Numerical Tool (TNT), a Fourier-based postprocessing code that enables real-time assessment of plasma systems. TNT performance was explored with visible and infrared interferometry in pulsed-power-driven
$Z$
-pinch configurations to expand its capabilities beyond Talbot X-ray interferometry in the high-intensity laser environment. TNT enabled accurate electron density characterization of magnetically driven plasma flows and shocks through phase-retrieval methods that did not require data modification or masking. TNT demonstrated enhanced resolution, detecting below 4
$\%$
fringe shift, which corresponds to 8.7
$\times$

$10^{15}$
cm
$^{-2}$
within 28
$\mu$
m, approaching the laser probing system limit. TNT was tested against a well-known interferometry analysis software, delivering an average resolving power nearly ten times better (
$\sim$
28
$\mu$
m versus
$\sim$
210
$\mu$
m) when resolving plasma ablation features. TNT demonstrated higher sensitivity when probing sharp electron density gradients in supersonic shocks. A maximum electron areal density of 4.1
$\times$

$10^{17}$
cm
$^{-2}$
was measured in the shocked plasma region, and a minimum electron density detection of
$\sim$
1.0
$\times$

$10^{15}$
cm
$^{-2}$
was achieved. When probing colliding plasma flows, the calculations of the effective adiabatic index and the associated errors were improved from
$\gamma^*=2.6 $

$\pm $

$1.6$
–
$1.4$

$\pm$

$ 0.2$
with TNT postprocessing, contributing valuable data for the interpretation of radiative transport. Additional applications of TNT in the characterization of pulsed-power plasmas and beyond are discussed.