New Thomson scattering diagnostic on RFX-mod

Journal Article · Mon Jan 15 04:00:00 EST 2007 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2431769· OSTI ID:20953240

Alfier, A; Pasqualotto, R ^[1]

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1. Dipartamento di Fisica G. Galilei, Universita degli Studi di Padova, Via Marzolo 8, I-35100 Padova, Italy and Consorzio RFX-Associazione Euratom-Enea sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy)

This article describes the completely renovated Thomson scattering (TS) diagnostic employed in the modified Reversed Field eXperiment (RFX-mod) since it restarted operation in 2005. The system measures plasma electron temperature and density profiles along an equatorial diameter, measuring in 84 positions with 7 mm spatial resolution. The custom built Nd:YLF laser produces a burst of 10 pulses at 50 Hz with energy of 3 J, providing ten profile measurements in a plasma discharge of about 300 ms duration. An optical delay system accommodates three scattering volumes in each of the 28 interference filter spectrometers. Avalanche photodiodes detect the Thomson scattering signals and allow them to be recorded by means of waveform digitizers. Electron temperature is obtained using an alternative relative calibration method, based on the use of a supercontinuum light source. Rotational Raman scattering in nitrogen has supplied the absolute calibration for the electron density measurements. During RFX-mod experimental campaigns in 2005, the TS diagnostic has demonstrated its performance, routinely providing reliable high resolution profiles.

• OSTI ID: 20953240
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 1 Vol. 78; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CALIBRATION
DENSITY
DIGITIZERS
ELECTRON DENSITY
ELECTRON TEMPERATURE
ION TEMPERATURE
LASERS
LIGHT SOURCES
LITHIUM COMPOUNDS
NITROGEN
PHOTODIODES
PLASMA
PLASMA DENSITY
PLASMA DIAGNOSTICS
REVERSE-FIELD PINCH
REVERSED-FIELD PINCH DEVICES
SPATIAL RESOLUTION
SPECTROMETERS
THOMSON SCATTERING