15-19 April 2018
Paradise Point Resort & Spa
America/Los_Angeles timezone

14.27 First Results from a High Time-Resolution Thomson Scattering System Applied to Pellet Fuelled Wendelstein 7-X Plasmas

19 Apr 2018, 10:30
2h 1m
Paradise Point Resort & Spa

Paradise Point Resort & Spa

1404 Vacation Rd, San Diego, CA 92109

Speakers

Hannes Damm (Max-Planck-Institut for Plasma Physics) Jürgen Baldzuhn (Max-Planck-Institut for Plasma Physics) Sergey Bozhenkov (Max-Planck-Institut for Plasma Physics) Andreas Dinklage (Max-Planck-Institut for Plasma Physics) Golo Fuchert (Max-Planck-Institut for Plasma Physics) Ekkehard Pasch (Max-Planck-Institut for Plasma Physics) Evan Scott (Max-Planck-Institut for Plasma Physics) Robert Wolf (Max-Planck-Institut for Plasma Physics)

Description

Studies of transient plasma events may reveal fast relaxation mechanisms of the plasma pressure or MHD events. A particular application specifying measurement requirements is the fuelling of fusion plasmas with cryogenic pellets. The paper describes a Thomson Scattering System, simultaneously providing electron temperature and density profiles, combining high temporal resolution and adjustable measuring times. This “burst” Thomson Scattering mode has a 10 kHz time resolution for repetitive bursts of typically 1.2 ms duration, compared to the 10 Hz standard mode. A burst can be either triggered at pre-defined times or by plasma events, for which a fast trigger logic circuit was developed. Currently, a single laser is employed emitting four laser pulses per burst. For the next campaign three lasers will be available providing twelve consecutive measurement points with 100 µs spacing. Burst measurements of pellet series have been conducted to demonstrate the viability of the approach. The event trigger employed the Hα emission of the pellet. Magnetic high and low field side pellet injections were compared. The assessment of potential grad-B effects did not show differences for different fuelling geometries. However, within a pellet series the deposition depth per pellet increased.

Primary author

Hannes Damm (Max-Planck-Institut for Plasma Physics)

Co-authors

Jürgen Baldzuhn (Max-Planck-Institut for Plasma Physics) Sergey Bozhenkov (Max-Planck-Institut for Plasma Physics) Andreas Dinklage (Max-Planck-Institut for Plasma Physics) Golo Fuchert (Max-Planck-Institut for Plasma Physics) Ekkehard Pasch (Max-Planck-Institut for Plasma Physics) Evan Scott (Max-Planck-Institut for Plasma Physics) Robert Wolf (Max-Planck-Institut for Plasma Physics)

Presentation Materials

There are no materials yet.
Your browser is out of date!

Update your browser to view this website correctly. Update my browser now

×