Ion-Current Downstream of a Carbon Dioxide Helicon Double Layer

Transport of ion beam in an annular magnetically expanding helicon double layer thruster

Experimental evidence of a double layer in a large volume helicon reactor.

The self-consistently generated current-free electric double layer (DL) is shown to scale up with the source tube diameter and appears not to be affected by rf driving frequency and changes in reactor geometry. This Letter presents the first simultaneous measurements of local plasma potential and beam energy as a function of axial position. The DL is shown to be no more than 5 mm thick (20 D le...

Ion Mobility Spectrometry in Carbon Dioxide

Heating rates of 20-30 "C gave satisfactory results for several additives, but no effort was made to establish an optimum heating rate. Extraction of polypropylene pellets with acetonitrile a t room temperature overnight gave clear evidence for the additives, but the extraction was approximately 2% efficient. Extraction with boiling decalin (4, 5) gave 0.053 wt 70 UV-531 in this sample. The sam...

Radial characterization of the electron energy distribution in a helicon source terminated by a double layer

Electron energy probability functions EEPFs are measured across the radius 0 r 6.85 cm of a low pressure 0.3 mTorr helicon plasma source terminated by a current-free double layer. The source field of about 130 G is generated using a Helmholtz coil pair and the radio frequency rf power is maintained at 250 W. All EEPFs exhibit a distribution with a temperature Te bulk out to a break energy break...

Observations of ion-beam formation in a current-free double layer.

With nonperturbative laser-induced fluorescence measurements of ion flow, we confirm numerical simulations of spontaneous electric double-layer (DL) formation in a current-free expanding plasma. Measurements in two different experiments confirm that the DL is localized to the region of rapidly diverging magnetic field. The measurements indicate that the trapped ion population is a single Maxwel...