@article{7624,
  author = {P. Lauber and I.G.J. Classen and D. Curran and V. Igochine and B. Geiger and S. da Graca and M. García-Muñoz and M. Maraschek and P. McCarthy},
  title = {NBI-driven Alfvenic modes at ASDEX Upgrade},
  abstract = {A large variety of electromagnetic modes excited by NBI-generated energetic ions are observed in the early phase of many discharges at ASDEX Upgrade. In addition to the well-known reversed shear Alfven eigenmodes (RSAE) and the toroidal Alfven eigenmodes (TAE), a set of modes around 70 kHz is observed as recently described in [7]. The modes were identified to be beta-induced Alfven eigenmodes (BAE) connected with the appearance of the q = 2 and the q = 1.5 surface during the current ramp-up phase. In the view of ITER, these BAEs may occur in scenarios with q approximate to 2 (scenario 4) and therefore add significantly to the transport of energetic ions due to RSAEs and TAEs. Experimentally, the combination of ECE, soft-x-ray and magnetic measurements allows for a very reliable mode position and mode structure determination. The measurements are compared with linear gyrokinetic calculations employing the LIGKA code that uses a fully kinetic model to describe fast-particle-driven modes in general tokamak geometry.},
  year = {2012},
  journal = {Nuclear Fusion},
  volume = {52},
  pages = {094007 },
  month = {Sep},
  isbn = {0029-5515},
  doi = {10.1088/0029-5515/52/9/094007 },
  language = {English},
}