Collective behaviors of fast ions accelerated by Ion Cyclotron Resonance Heating
نویسندگان
چکیده
Introduction This work focuses on fast ion transport caused by collective modes and the corresponding evolution of meso-scale fluctuations in burning plasma. More specifically, we analyze these problems in the FAST (Fusion Advanced Studies Torus) [1] H-mode reference scenario, a conceptual design proposal for a EU ITER Satellite tokamak. As explained in [2], FAST approaches dimensionless parameters ρ∗ H = ρH,L/a (ρH,L is the fast ions Larmor radius and a the minor radius of the torus), βH = 8πPH/B 2 ( PH is the fast ion scalar pressure and B the intensity of the magnetic field) and geometry of ITER in a smaller device. In this way it can investigate some of the relevant α particle physics of ITER, using a D plasma with a He minority heated by Ion Cyclotron Resonance Heating (ICRH). Here and in the following the subscript H stands for suprathermal minority (Hot) particles. In this work, we briefly discuss perpendicular and parallel temperatures radial profiles, charactreristic of the FAST H-mode reference scenario, and the spatial density radial distributions of the energetic ion minority tail fraction, respectively denoted by TH,⊥(r),TH,‖(r) and nH(r), with r being the minor radius coordinate. We then simulate the fast ion behavior using HMGC [3], a 3-D hybrid MHD-Gyrokinetic simulation code. Linear and saturated spectra are presented together with numerical simulation results on fast particle transport due to Alfvén mode excitation for moderate toroidal mode numbers, n = 4 and 8.
منابع مشابه
Impact of ICRH on the Measurement of Fast Ions by Collective Thomson Scattering in ITER
Collective Thomson scattering (CTS) has been proposed for measuring the phase space distribution of confined fast ion populations in ITER plasmas. This study determines the impact of fast ions accelerated by ion cyclotron resonance heating (ICRH) on the ability of CTS to diagnose fusion alphas in ITER. The investigated ICRH scenarios include pure second harmonic tritium heating and He minority ...
متن کاملMinority heating by ICRH: a tool for investigating burning plasma physics in FAST
A combined Fokker–Planck numerical analysis of the quasi-linear plasma–ion-cyclotron (IC) wave interaction and collisional relaxation of minority ion tails created by IC absorption was performed in order to determine the characteristic fast-ion parameters that are necessary for addressing some of the main ITER burning plasma physics issues, e.g. fast-ion transport due to collective mode excitat...
متن کاملSolar off - limb line widths : Alfvén waves , ion - cyclotron waves , and preferential heating
Context. Alfvén waves and ion-cyclotron absorption of high-frequency waves are frequently brought into models devoted to coronal heating and fast solar-wind acceleration. Signatures of ion-cyclotron resonance have already been observed in situ in the solar wind (HELIOS spacecrafts) and, recently, in the upper corona (UVCS/SOHO remote-sensing results). Aims. We propose a method to constrain both...
متن کاملMeasurements of fast-ion acceleration at cyclotron harmonics
Combined neutral beam injection and fast wave heating at the fourth and fifth cyclotron harmonics accelerate fast ions in the DIII-D tokamak. Measurements with a nine-channel fast-ion D-alpha (FIDA) diagnostic indicate the formation of a fast-ion tail above the injection energy. Tail formation correlates with enhancement of the d–d neutron rate above the value that is expected in the absence of...
متن کامل