Author/Authors :
Narihara، نويسنده , , K and Yamauchi، نويسنده , , K and Yamada، نويسنده , , I and Minami، نويسنده , , T and Adachi، نويسنده , , K and Ejiri، نويسنده , , A and Hamada، نويسنده , , Y and Ida، نويسنده , , K and Iguchi، نويسنده , , H and Kawahata، نويسنده , , K and Ozaki، نويسنده , , T and Toi، نويسنده , , K، نويسنده ,
Abstract :
Thomson scattering; systems diagnosing three regions of the large helical device (LHD) are presented. (1) An obliquely back-scattered Thomson scattering system gives full profiles of electron temperature (Te) and density (ne) along the major radius on the mid-plane with a spatial resolution of 1.5–4.0 cm. A piezo-actuated mirror is dynamically oriented so that the beams from ten 50 Hz repetition rate Nd:YAG lasers propagate a common path along a major radius, giving Te and ne profiles every 2 ms. (2) A cavity Thomson scattering system will measure two-dimensional Te and ne profiles along the laser beam propagating off-axially right and left in an optical cavity. This will diagnose the island structures in the outer edge region. (3) A fiber Thomson scattering system, in which laser light is guided by an optical fiber, is freely movable and conveniently used to probe the diverted plasma.
