Related Experiment Video
Updated: Jun 20, 2026
07:10
3D Depth Profile Reconstruction of Segregated Impurities Using Secondary Ion Mass Spectrometry
Published on: April 29, 2020
Deconvolution-based correction of alkali beam emission spectroscopy density profile measurements
1Department of Radio and Space Science, Chalmers University of Technology, EURATOM-VR Association, SE-41296 Göteborg, Sweden.
The Review of Scientific Instruments
|September 4, 2009
Summary
A new deconvolution method improves beam emission spectroscopy (BES) density profile measurements in tokamaks by correcting for signal smoothing. This technique enhances accuracy in fusion plasma research.
Area of Science:
- Plasma Physics
- Fusion Energy Research
- Spectroscopy Techniques
Background:
- Beam Emission Spectroscopy (BES) is crucial for measuring plasma density profiles in fusion devices.
- Measurement inaccuracies can arise from the finite width of the diagnostic beam and viewing geometry.
- Existing methods may underestimate plasma density due to signal smoothing effects.
Purpose of the Study:
- To demonstrate a deconvolution-based correction method for BES density profile measurements.
- To quantify the systematic error caused by observation effects in tokamaks.
- To validate the effectiveness of an emission reconstruction method in reducing this error.
Main Methods:
- Application of a deconvolution-based emission reconstruction method to simulated BES data.
- Utilizing the alkali BES simulation code RENATE for comprehensive analysis.
- Investigating measurements from COMPASS and TEXTOR tokamak scenarios.
Main Results:
- The study identified significant underestimation of plasma density profiles due to signal smoothing.
- The emission reconstruction method effectively reduces this systematic error.
- The method accounts for finite beam width and measurement transfer functions.
Conclusions:
- Deconvolution-based emission reconstruction is a vital technique for accurate BES density profile measurements.
- This method significantly improves the reliability of density profile data in fusion research.
- Accurate density profiles are essential for understanding and controlling fusion plasmas.
More Related Videos
09:53Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation
Published on: October 30, 2012
10:03Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Related Concept Videos
01:14NMR Spectrometers: Resolution and Error Correction
When magnetic nuclei in a sample achieve resonance and undergo relaxation, the signal detected in NMR is an approximately exponential free induction decay. Fourier transform of an exponential decay yields a Lorentzian peak in the frequency domain. Lorentzian peaks in an NMR spectrum are defined by their amplitude, full width at half maximum, and position, where the peak width is governed by the spin-spin relaxation time alone. In real experiments, however, the applied magnetic field is rendered...
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
01:09UV–Vis Spectroscopy: Beer–Lambert Law
The Beer-Lambert law describes the relationship between absorbance and concentration, which combines the principles established by scientists Johann Heinrich Lambert and August Beer. Lambert's law states that when light passes through a medium, the loss in intensity is directly proportional to the original intensity and the path length of the light. Beer's law proposed that the transmittance of a solution remains constant if the product of concentration and path length is constant. The modern...
01:30Atomic Emission Spectroscopy: Interference
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
01:25Atomic Absorption Spectroscopy: Atomization Methods
Atomic Absorption Spectroscopy (AAS) atomizes samples through flame atomization or electrothermal atomization. Flame atomization typically involves a nebulizer and spray chamber assembly to combine the sample with a fuel–oxidant mixture, creating a fine aerosol mist that enters a burner. Typically, the fuel and oxidant are combined in an approximately stoichiometric ratio. However, for atoms that are easily oxidized, a fuel-rich mixture may be more advantageous. Only about 5% of the aerosol...
01:29Atomic Emission Spectroscopy: Lab
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...