Contributo in atti di convegno, 2021, ENG

Helium doped plasmas on FTU

Mazzotta C.; Pucella G.; Apruzzese G.; Boncagni L.; Carraro L.; Castaldo C.; Ceccuzzi S.; Cesaroni S.; Cianfarani C.; Claps G.; Coppi B.; D'Arcangelo O.; Di Troia C.; Esposito B.; Gabellieri L.; Giovannozzi E.; Iafrati M.; Maddaluno G.; Marinucci M.; Palomba S.; Puiatti M.E.; Romano A.; Senni L.; Tudisco O.; Zotta V.K.

ENEA C. R. Frascati, Dipartimento FSN, Frascati, Italy; Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova - CNR ISTP, Istituto per la Scienza e Tecnologia dei Plasmi, Sede di Padova, Italy; Università di Tor Vergata, Rome, Italy; Massachusetts Institute of Technology (MIT), Cambridge, MA USA; Department of Astronautical, Electrical and Energy Engineering, Sapienza-Università di Roma, Italy.

In order to extend observations on the spontaneous electron density peaking in Neon doped plasmas already reported in FTU [1], some sessions have been performed by injecting Helium gas on the L-mode plasmas during the last two experimental campaigns. This favorable scenario, which can fall within so called "highly radiative" or "plasma detachment" themes, is investigated in this paper. It has been recorded that, not only the total amount of puffed Helium, but also the rate of injection can intervene in triggering a particle inflow. VUV spectroscopy measurements can help to evaluate the fraction of electrons that can be attributed to the ones stripped by Helium ionization in the electron density rise, at this purpose a model to estimate concentrations of impurities is proposed. The description of the Helium effect on plasma behavior, especially with respect to the density peaking and edge conditioning, by varying plasma parameters and shape, is exposed.

FEC 2020 - 28th IAEA Fusion Energy Conference, pp. 1–8, Virtual Event Europe/Vienna timezone, 10-15 May 2021

Keywords

Helium doped plasmas, FTU

CNR authors

Carraro Lorella

CNR institutes

ISTP – Istituto per la Scienza e Tecnologia dei Plasmi