The characteristic geometry of a pulsed capillary discharge (PCD), a narrow open end tube with a large aspect ratio, establishes natural conditions for the generation of plasma jets, that propagate in the neutral background gas surrounding the capillary. We have investigated the plasma jet emission in a PCD, with electron beam assisted on-axis initiation. A local storage capacitor, coaxial with the capillary assembly, is pulse charged up to a maximum of -11 kV, which results in an initial ∼ 10 ns, ∼ 2 kA current pulse. The discharge is operated in Argon and Nitrogen, in a continuous pulsing mode, at frequencies between 5 to 20 Hz, and in a pressure range between 300 to 1100 Torr. A fast Langmuir probe, placed at the anode side, close to the capillary exit, is used to measure the characteristic electron temperature (Te) and electron density (Ne) of the plasma jets. Results obtained in Nitrogen at 10 Hz indicate that Te is in the 10 to 60 eV range with Ne of the order of 1014 (cm-3). Significant changes in the probe floating potential are observed for a fixed operating pressure when the pulsing frequency is varied, which can be ascribed to the presence of metastables in the gas fed into the capillary, which result from the interaction of the plasma jet with the plenum gas, at the cathode side. The presence of metastables reduces the energy cost involved in the capillary plasma production, which results in a pulsing frequency dependence of the plasma parameters. © 2006 American Institute of Physics.
Documento: | Artículo |
Título: | Properties of plasma jets emitted in pulsed capillary discharges at low pressures |
Autor: | Avaria, G.; Bhuyan, H.; Favre, M.; Chuaqui, H.; Mitchell, I.; Wyndham, E.; Grondona, D. |
Ciudad: | Mexico-City |
Filiación: | Departamento de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22, Chile Departamento de Física, Facultad de Ciencias Exactas y Naturales, Pabellón 1, 1428,Buenos Aires, Argentina |
Año: | 2006 |
Volumen: | 875 |
Página de inicio: | 393 |
Página de fin: | 396 |
DOI: | http://dx.doi.org/10.1063/1.2405972 |
Título revista: | PLASMA AND FUSION SCIENCE: 16th IAEA Technical Meeting on Research using Small Fusion Devices; XI Latin American Workshop on Plasma Physics |
Título revista abreviado: | AIP Conf. Proc. |
ISSN: | 0094243X |
PDF: | https://bibliotecadigital.exactas.uba.ar/download/paper/paper_0094243X_v875_n_p393_Avaria.pdf |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0094243X_v875_n_p393_Avaria |