Measurements with the KSTAR Beam Emission Spectroscopy diagnostic system Máté Lampert Wigner...
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Measurements with the KSTAR Beam Emission Spectroscopy diagnostic system Máté Lampert Wigner Research Centre for Physics Hungarian Academy of Sciences Budapest, Hungary E-mail: [email protected]3rd FUSENET PhD event - 2013. 06. 25. – Máté Lampert – Overview of the final Beam Emission Spectroscopy Diagnosic on KSTAR
Measurements with the KSTAR Beam Emission Spectroscopy diagnostic system Máté Lampert Wigner Research Centre for Physics Hungarian Academy of Sciences
Measurements with the KSTAR Beam Emission Spectroscopy
diagnostic system Mt Lampert Wigner Research Centre for Physics
Hungarian Academy of Sciences Budapest, Hungary E-mail:
[email protected] 3rd FUSENET PhD event - 2013. 06. 25. Mt
Lampert Overview of the final Beam Emission Spectroscopy Diagnosic
on KSTAR
Slide 2
Introduction to BES 2 Plasma transport is dominated by
turbulence causing fluctuations in plasma parameters Beam Emission
Spectroscopy (BES) is a suitable method for measuring fluctuations:
The plasma is being heated by the Neutral Beam Injection (NBI) The
particles of the beam are excited and emit light The intensity of
the light is roughly proportional to the plasma density By
measuring the light intensity, one can get information about
turbulence From the movement of turbulence eddies, flow velocity
can be determined Two important design constraints: Sufficient
Doppler-shift (separation from edge D ) View along field lines
(spatial resolution) 3rd FUSENET PhD event - 2013. 06. 25. Mt
Lampert Overview of the final Beam Emission Spectroscopy Diagnosic
on KSTAR Schematic view of a BES system
Slide 3
BES diagnostic setup 3 Design aspects: Direct imaging from
plasma to multi-channel detector Combined system for HBES and LiBES
measurements Wavelength: H: ~662nm (Doppler shifted H ), Li:~670nm
APDCAM (Avalanche Photo Diode Camera): 4 x 8 channel array @
2.000.000 frame/sec 1cm by 1cm per channel spatial resolution 4cm x
8cm of the plasma is measured at one shot Continuously adjustable
from r/a = 0.1 to r/a = 1 CCD camera: inter-shot spatial
calibration, 100Hz beam imaging, full minor radius, 640x480 Lithium
beam density profile measurements Novel design features of the
system: Heatable and rotateable filter for Wavelength tuning Filter
changer for Lithium and Deuterium beam measurements Rotateable
APDCAM for horizontal (4x8) and vertical (8x4) measurement
Deuterium Beam APDCAM Periscope in M-port Tilting mirror at two
angles CCD camera 3rd FUSENET PhD event - 2013. 06. 25. Mt Lampert
Overview of the final Beam Emission Spectroscopy Diagnosic on
KSTAR
Slide 4
The BES system Rotatable mirror CCD arm Inside M port Outside
Filter APDCAM Plasma Prism Front mirror APDCAM Stepmotor for mirror
rotation To CCD 3rd FUSENET PhD event - 2013. 06. 25. Mt Lampert
Overview of the final Beam Emission Spectroscopy Diagnosic on KSTAR
4 BES tower BES installed in M port
Slide 5
Measurement possibilities 5 The BES system was operated by me
during the 1000 shots of the 2012 campaign The system is capable of
measuring: Turbulence Amplitude, wavelength Poloidal velocity 3D
fluctuation together with Electron Cyclotron Emission imaging
Signals are analyzed through Fourier / correlation methods During
steady state plasma Radial density profile measurement (when NBI is
modulated) Measured signal for shot 7177 3rd FUSENET PhD event -
2013. 06. 25. Mt Lampert Overview of the final Beam Emission
Spectroscopy Diagnosic on KSTAR
Slide 6
Turbulence detection 6 Fluctuation level and noise level
r/a=0.65 r/a=0.8 r/a=0.85r/a=1 Separatrix Core measurement:
(r/a~0.7-0.8) SNR 60 Fluctuation amplitude is low Around 1 - 1.5%
Noise level is 1.5 times higher then fluctuation Turbulence is hard
to detect Edge measurement: (r/a ~ 0.9-1) SNR 45 Fluctuation
amplitude is higher Around 3 - 4% Noise level is around the
fluctuation level at channel 3 Turbulence can be detected
Background fluctuation (