Related Experiment Video
Updated: Feb 3, 2026

Measurement of Spatial Stability in Precision Grip
Published on: June 4, 2020
Variable location channels to improve efficiency and precision for direct ∇T measurements and high spatial
S Houshmandyar1, M E Austin1, M W Brookman1
1Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712, USA.
Abstract:
Electron cyclotron emission (ECE) diagnostics that use variable location channels based on yttrium iron garnet (YIG) bandpass filters improve the precision and the efficiency of measurements of electron temperature (T ) profiles and fluctuations (δT ). These variable frequency filters were substituted for fixed frequency filters in the intermediate frequency section to achieve the required higher resolution over a target radial range, just before the experiment. Here, we present the proof-of-principle for high temporal resolution measurement of the electron temperature gradient, via real-time slewing of a YIG filter for relocation of an ECE channel during a long pulse. The key component is the application of YIG tunable filters with their narrow bandwidth and capability for a high slew rate of their center frequency. This application permits fast relocation of the ECE channels for direct measurement of the gradient and close spacing of channels to investigate the magnetic island's dynamic behavior.
Related Concept Videos
Uncertainty in Measurement: Accuracy and Precision
Electronic Distance Measuring Instruments
Emission Spectra
Microbial Growth Measurement: Direct Methods
Uncertainty in Measurement: Significant Figures
Uncertainty in Measurement: Reading Instruments

