TY - JOUR

T1 - TORBEAM 2.0, a paraxial beam tracing code for electron-cyclotron beams in fusion plasmas for extended physics applications

AU - Poli, E.

AU - Bock, A.

AU - Lochbrunner, M.

AU - Maj, O.

AU - Reich, M.

AU - Snicker, A.

AU - Stegmeir, A.

AU - Volpe, F.

AU - Bertelli, N.

AU - Bilato, R.

AU - Conway, G. D.

AU - Farina, D.

AU - Felici, F.

AU - Figini, L.

AU - Fischer, R.

AU - Galperti, C.

AU - Happel, T.

AU - Lin-Liu, Y. R.

AU - Marushchenko, N. B.

AU - Mszanowski, U.

AU - Poli, F. M.

AU - Stober, J.

AU - Westerhof, E.

AU - Zille, R.

AU - Peeters, A. G.

AU - Pereverzev, G. V.

PY - 2018/4

Y1 - 2018/4

N2 - The paraxial WKB code TORBEAM (Poli, 2001) is widely used for the description of electron-cyclotron waves in fusion plasmas, retaining diffraction effects through the solution of a set of ordinary differential equations. With respect to its original form, the code has undergone significant transformations and extensions, in terms of both the physical model and the spectrum of applications. The code has been rewritten in Fortran 90 and transformed into a library, which can be called from within different (not necessarily Fortran-based) workflows. The models for both absorption and current drive have been extended, including e.g. fully-relativistic calculation of the absorption coefficient, momentum conservation in electron–electron collisions and the contribution of more than one harmonic to current drive. The code can be run also for reflectometry applications, with relativistic corrections for the electron mass. Formulas that provide the coupling between the reflected beam and the receiver have been developed. Accelerated versions of the code are available, with the reduced physics goal of inferring the location of maximum absorption (including or not the total driven current) for a given setting of the launcher mirrors. Optionally, plasma volumes within given flux surfaces and corresponding values of minimum and maximum magnetic field can be provided externally to speed up the calculation of full driven-current profiles. These can be employed in real-time control algorithms or for fast data analysis.

AB - The paraxial WKB code TORBEAM (Poli, 2001) is widely used for the description of electron-cyclotron waves in fusion plasmas, retaining diffraction effects through the solution of a set of ordinary differential equations. With respect to its original form, the code has undergone significant transformations and extensions, in terms of both the physical model and the spectrum of applications. The code has been rewritten in Fortran 90 and transformed into a library, which can be called from within different (not necessarily Fortran-based) workflows. The models for both absorption and current drive have been extended, including e.g. fully-relativistic calculation of the absorption coefficient, momentum conservation in electron–electron collisions and the contribution of more than one harmonic to current drive. The code can be run also for reflectometry applications, with relativistic corrections for the electron mass. Formulas that provide the coupling between the reflected beam and the receiver have been developed. Accelerated versions of the code are available, with the reduced physics goal of inferring the location of maximum absorption (including or not the total driven current) for a given setting of the launcher mirrors. Optionally, plasma volumes within given flux surfaces and corresponding values of minimum and maximum magnetic field can be provided externally to speed up the calculation of full driven-current profiles. These can be employed in real-time control algorithms or for fast data analysis.

KW - Electron cyclotron waves

KW - Magnetic confinement

KW - Paraxial beam tracing

KW - Plasma physics

KW - Wave–plasma interactions

UR - http://www.scopus.com/inward/record.url?scp=85041108323&partnerID=8YFLogxK

U2 - 10.1016/j.cpc.2017.12.018

DO - 10.1016/j.cpc.2017.12.018

M3 - Article

AN - SCOPUS:85041108323

SN - 0010-4655

VL - 225

SP - 36

EP - 46

JO - Computer Physics Communications

JF - Computer Physics Communications

ER -