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Updated: Jun 7, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Preliminary results from the Alcator C-Mod polarimeter
P Xu1, J H Irby, W F Bergerson
1Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. pxu@mit.edu
The Review of Scientific Instruments
|November 2, 2010
Summary
A new far infrared polarimeter diagnostic is being developed for the Alcator C-Mod tokamak to measure plasma properties. Initial tests show acceptable noise levels for studying magnetic field fluctuations and the q-profile.
Area of Science:
- Plasma physics
- Fusion energy research
- Diagnostic instrumentation
Background:
- The Alcator C-Mod tokamak requires advanced diagnostics for plasma characterization.
- Understanding the q-profile and fluctuations is crucial for fusion energy development.
Purpose of the Study:
- Develop and test a poloidally viewing far infrared polarimeter diagnostic.
- Determine the safety factor (q-profile) and study plasma fluctuations.
- Assess the feasibility of a multi-chord system for comprehensive measurements.
Main Methods:
- Design and fabrication of a three-chord polarimeter system.
- Bench testing of a single-chord mock-up.
- Analysis of noise sources and reduction techniques.
Main Results:
- A three-chord system has been designed and fabricated for installation.
- Bench tests indicate acceptable noise levels for planned measurements.
- Techniques for diagnosing and reducing noise have been identified.
Conclusions:
- The developed polarimeter diagnostic is suitable for Alcator C-Mod.
- The system will provide valuable data on the q-profile and plasma fluctuations.
- Further development towards a ten-chord system is planned.
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