Speaker
Pavel Hacek
(Faculty of Mathematics and Physics)
Description
Atomic beam probe (ABP) is a diagnostic tool using a detection of ions coming from an ionized part of a diagnostic beam in tokamaks. The method allows measurements of plasma density fluctuations and fast variations in the poloidal magnetic field. Therefore, it gives the possibility to follow fast changes of edge plasma current, e.g. during ELMs in H-mode.
The test detector has been installed on the COMPASS tokamak as an extension of the existing lithium beam diagnostic system. It uses a relatively simple set-up based on an array of conductive detection plates measuring the incident ion current, which is then amplified and converted to a voltage signal.
The proof-of-concept measurements with the test detector has been done partly in laboratory and partly on the COMPASS tokamak. The concept and results of these measurements are the main targets of this contribution.
For the proper interpretation of measured data the ion trajectories in the magnetic field of the COMPASS tokamak must be calculated by solving numerically the equations of motion. The ABPIons code has been developed in MATLAB, in order to calculate positions of ions sequentially after every time step of the numerical scheme. TAIGA code is developed on the CUDA graphical processor, therefore, it is a parallel code calculating positions of ions, in the detector's plane only. Results of simulations from both codes will be also presented.
Test measurements with ABP test detector installed on the COMPASS tokamak supported with simulation codes clearly proved that measured signals on detector plates are caused mainly by Li-ions stemming from the diagnostic beam.
Co-authors
Attila Bencze
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Daniel Dunai
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Gabor Anda
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Jan Stockel
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Jaroslav Krbec
(Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19, Prague 1, Czech Republic;Tokamak Department, Institute of Plasma Physics of the Czech Academy of Sciences, Za Slovankou 1782/3, 182 00, Prague 8, Czech Republic)
Matyas Aradi
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Miklos Berta
(Szechenyi Istvan University, H-9026 Gyor, Egyetem ter 1., Hungary)
Pavel Hacek
(Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16, Prague 2, Czech Republic;Tokamak Department, Institute of Plasma Physics of the Czech Academy of Sciences, Za Slovankou 1782/3, 182 00, Prague 8, Czech Republic)
Sandor Zoletnik
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
Vladimir Weinzettl
(Department of Plasma Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, 29-33 Konkoly Thege Miklos ut, Budapest, XII., H-1121, Hungary)
