scholarly journals Soft X-ray spectra of Cerium laser-produced plasmas

2021 ◽  
Author(s):  
Elgiva White ◽  
Gerard O'Sullivan ◽  
Padraig Dunne
Keyword(s):  
Yttrium Aluminium Garnet ◽  
Final States ◽  
X Ray ◽  
Yttrium Aluminium ◽  
Target Ranging ◽  
Atomic Structure Calculations ◽  
Power Densities ◽  
Structure Calculations ◽  
532 Nm ◽  
Transition Array

Abstract Spectra of laser-produced plasmas of cerium have been recorded in the 1.5 to 15.5 nm spectral region. The plasmas were formed using the frequency doubled pulsed output of a neodymium-doped yttrium aluminium garnet (Nd:YAG) laser at 532 nm. At the power densities incident on-target, ranging from 8.6×109- 2.1×1013W cm-2, Ce4+ to Ce27+ ions gave rise to emission from ∆n = 0, 1 transitions to final states where n = 4. The spectra are dominated by an intense unresolved transition array (UTA) in the 8-10 nm region arising from n = 4 to n = 4 transitions. Two distinct components of this UTA are observed whose appearance is strongly dependent on laser power density, corresponding to transitions involving ions with open 4d and open 4f subshells, the latter at longer wavelengths. Multiple other transition arrays are identified and UTA statistics are given. The analysis was aided by atomic structure calculations and the use of a steady state collisional-radiative (CR) model.

Soft-X-ray spectra of highly charged Au ions in an electron-beam ion trap

2001 ◽  
Vol 79 (2-3) ◽  
pp. 153-162 ◽  
Author(s):  
E Träbert ◽  
P Beiersdorfer ◽  
K B Fournier ◽  
S B Utter ◽  
K L Wong
Keyword(s):  
Electron Beam ◽  
Beam Energy ◽  
Large Scale ◽  
Ion Trap ◽  
Electron Beam Energy ◽  
X Ray ◽  
Maximum Charge ◽  
Electron Beam Ion Trap ◽  
Atomic Structure Calculations ◽  
Structure Calculations

Systematic variation of the electron-beam energy in an electron-beam ion trap has been employed to produce soft-X-ray spectra (20 to 60 Å) of Au with well-defined maximum charge states ranging from Br- to Co-like ions. Guided by large-scale relativistic atomic structure calculations, the strongest Δn = 0 (n = 4 to n' = 4) transitions in Rb- to Cu-like ions (Au42+ – Au50+) have been identified. PACS Nos.: 32.30Rj, 39.30+w, 31.50+w, 32.20R

scholarly journals TIPTOPbase

2005 ◽  
Vol 13 ◽  
pp. 662-665
Author(s):  
P. Palmeri ◽  
C. Mendoza
Keyword(s):  
Atomic Structure ◽  
Atomic Data ◽  
Virtual Observatory ◽  
X Ray ◽  
Atomic Structure Calculations ◽  
Structure Calculations

AbstractAn overview of the online atomic database referred to as TIPTOPbase is given, in particular its opacity server (OPserver) and current developments regarding online atomic structure calculations. Efforts to include atomic data for X-ray line modeling and to integrate TIPTOPbase within the International Virtual Observatory Alliance (IVOA) are also mentioned.

Study on Preparation and Characterization of YAG Ceramic Synthesized by Co-Precipitation

2011 ◽  
Vol 284-286 ◽  
pp. 1317-1320
Author(s):  
Quan Shui Chen ◽  
Xiao Dong Liu ◽  
Guang Yuan Ren ◽  
Pan Yi Liang ◽  
Hui Ma
Keyword(s):  
Electron Probe ◽  
Precipitation Method ◽  
Yttrium Aluminium Garnet ◽  
Mineral Phase ◽  
X Ray ◽  
Yttrium Aluminium ◽  
Good Crystallinity ◽  
Co Precipitation ◽  
Scanning Electron

Yttrium Aluminium Garnet (YAG) has a extensive applications in many fields because of its excellent properties. In this study the products synthesized by co-precipitation method is regular, and the reaction is complete, the YAG ceramic obtained is white, its density is 2.42g/cm3 and shrinkage is 7.78%. The YAG ceramic tablets were investigated by Field emission scanning electron microscopy (FE-SEM), Electron probe microanalysis (EPMA) and X-ray diffractometer (XRD). The results show that the structure of YAG ceramic is loose with spherical grain size of 0.2-0.3μm. The main mineral phase of YAG ceramic is composed of polycrystalline Al5Y3O12 with good crystallinity, and containing very small amount of unreacted alumina and other impurities.

Picosecond 532-nm neodymium-doped yttrium aluminium garnet laser—a novel and promising modality for the treatment of café-au-lait macules

2017 ◽  
Vol 33 (4) ◽  
pp. 693-697 ◽  
Author(s):  
Ofir Artzi ◽  
Joseph N. Mehrabi ◽  
Amir Koren ◽  
Roni Niv ◽  
Moshe Lapidoth ◽  
...  
Keyword(s):  
Yttrium Aluminium Garnet ◽  
Yttrium Aluminium ◽  
532 Nm ◽  
Yttrium Aluminium Garnet Laser

scholarly journals X-Ray Spectroscopy to Determine Line Coincidences Between K- and L-Shell Transitions

1984 ◽  
Vol 86 ◽  
pp. 255-257
Author(s):  
P.G. Burkhalter ◽  
D. Newman ◽  
J.V. Gilfrich ◽  
D.B. Brown ◽  
P.D. Rockett ◽  
...  
Keyword(s):  
Spectral Line ◽  
Ab Initio ◽  
Conversion Efficiency ◽  
Atomic Structure ◽  
Current Effort ◽  
X Ray ◽  
Gain Measurement ◽  
Atomic Structure Calculations ◽  
Structure Calculations ◽  
Oxygen Fluorine

Accurate wavelengths for highly-ionized L-shell spectra were measured in the 10–16Å region. The purpose being to determine lines in coincidence with L-shell transitions from the elements oxygen, fluorine, and neon. L-shell transitions have been proposed for resonant photopumping of K-shell electrons in these elements to, generate lasing between upper levels in the 40–150 eV region. The current effort improves on and expands the earlier spectroscopic work performed at KMS Fusion, Inc., where possible line coincidences were identified for photoionizing in the 1–3 and 1–4 levels in fluorine. New experimental techniques have led to a wavelength accuracy now believed to be ± 2 mÅ for cases in which adequate calibration lines are available. Exact spectral line matches were found for Mn with the F H,-line at 12.643Å and for both Mn and Cr with the F He line at 14.458Å. The Mn line at 12.643Å has been identified, using ab initio atomic structure calculations, as the 1D2 − 1F3 transition in Be-like Mn XXII. The Mn line emissivity was determined to be 30 MW into 2 steradians for a conversion efficiency of 0.04%. Photopumping with Mn coated gasfilled targets is presently being tried in gain measurement experiments at LLNL.

Synthesis and Characterization of YAG:Ce Phosphor by Microwave Induced Combustion Synthesis with Different Fuel Sources

2020 ◽  
Vol 301 ◽  
pp. 69-76
Author(s):  
Khai Shenn Lau ◽  
Zainuriah Hassan ◽  
Way Foong Lim ◽  
Hock Jin Quah ◽  
Naser Mahmoud Ahmed ◽  
...  
Keyword(s):  
Combustion Synthesis ◽  
Luminescent Properties ◽  
Yttrium Aluminium Garnet ◽  
X Ray Diffraction ◽  
Mixed Fuel ◽  
X Ray ◽  
White Leds ◽  
Yttrium Aluminium ◽  
Cie Chromaticity

White LEDs (WLEDs) have been produced from the combination of blue LED chips and phosphor converter. In the present work, considerable amount of yttrium aluminium garnet (YAG) phosphor powders doped with 0.3 mol% of cerium (Ce) have been synthesized via Microwave Induced Combustion Synthesis (MICS) method with different fuel sources such as urea and mixed fuel of urea and glycine. The effects of different fuel sources on the crystallinity, structure, luminescent properties and Commision International de L’Eclairage (CIE) chromaticity was characterized and studied using high resolution X-ray diffraction (HR XRD), field emission-scanning electron microscopy (FE SEM), energy dispersive X-ray spectroscopy (EDX), electroluminescence (EL) and standard CIE 1931 chromaticity diagram, respectively. The highest EL intensity can be observed from the sample prepared by mixed fuel technique. In contrast, the experimental enhancement in the aforementioned properties was demonstrated by the WLED synthesized using mixed fuel technique. Keywords: White LEDs, phosphor converter, microwave induced combustion, mixed fuel technique.

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