Establishing an isoelectronic line ratio temperature diagnostic for soft X-ray absorption spectroscopy

Role of Simple Spatial Gradient in Reinforcing the Accuracy of Temperature Determination of HED Plasma via Spectral Line-Area Ratios

“…The experiments were performed on the Z Facility at SNL [12], using the Z Pinch Dynamic Hohlraum (ZPDH) [13], under the auspices of the Z Astrophysical Plasma Properties (ZAPP) collaboration [14]. As the materials and methods have been documented elsewhere [9,10], we provide only a summary of the experimental scenario. In particular, the ZPDH consists of a 120 tungsten wire array with an inner diameter of 20 mm, nested in a 240 tungsten wire, 40 mm diameter array [14].…”

“…Driven by the J × B force, ablated tungsten streams towards the z-pinch axis until stagnation, driving a radiating shock through the foam [15]. Due to the high opacity of the tungsten plasma, the shock radiation is trapped, effectively creating a hohlraum [9,15]. Crucially, this "dynamic" hohlraum can facilitate total X-ray energy and power exceeding 1.5 MJ and 200 TW, respectively [14,17].…”

“…In this study, we implement the collisional-radiative model PRISMSPECT [8] to construct synthetic absorption spectra, which are subsequently compared with data gathered from the Z Facility at SNL. In line with previous work that utilized line-area ratios to infer electron temperature in a radiatively-heated NaFMgO plasma [9,10], we investigate the robustness of line-area ratios in the presence of spatial gradients.…”

“…These values are chosen to reflect the results presented in refs. [9,10]. Guided by previous work [4][5][6]9,10,15,17,[19][20][21][22], we model our system as 1D, both for simplicity and efficiency.…”

“…Effectively, this report is an extension of line-ratio techniques documented in refs. [9][10][11] and elsewhere. Section 2 outlines the experimental set-up, while Section 3 details our hypothesis and various methods of data reduction.…”