Browsing by Author "Volpe, Francesco"

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    Full-wave modeling of the O-X mode conversion in the Pegasus toroidal experiment
    (2011) Köhn, Alf; Jacquot, Jonathan; Bongard, Michael W.; Gallian, Sara; Hinson, Edward T.; Volpe, Francesco
    The ordinary-extraordinary (O-X) mode conversion is modeled with the aid of a 2D full-wave code in the Pegasus toroidal experiment as a function of the launch angles. It is shown how the shape of the plasma density profile in front of the antenna can significantly influence the mode conversion efficiency and, thus, the generation of electron Bernstein waves (EBWs). It is therefore desirable to control the density profile in front of the antenna for successful operation of an EBW heating and current drive system. On the other hand, the conversion efficiency is shown to be resilient to vertical displacements of the plasma as large as ±10 cm.
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    Full-wave simulations of the O-X-B mode conversion in a realistic experimental geometry in the RFX-mod device
    (2011) Köhn, Alf; Bilato, Roberto; Volpe, Francesco; Paccagnella, Roberto
    A full-wave code has been used to model the O–X–B mode-conversion process in RFX-mod. Parameter scans were performed to find the optimum launching condition for the microwave beam. Vacuum walls play an important role in the overall conversion efficiency, which is a key parameter for the success of the experiment. This is nicely illustrated in simulations.