The paper reports on the development and application of a swept Langmuir probe to characterize plasma between two disc-like electrodes. A battery was added to a probe circuit to offset against the cathode fall voltage, and to make the sweep voltage effective at the probe tip. This arrangement allowed the collection of the electron and ion parts of the probe current and the subsequent construction of time-resolved current–voltage IP(V) characteristics with a time resolution of about one millisecond. The probe collected electron current in the lower voltage region of the discharge waveform where it surmounted the cathode fall voltage, whereas the ion current was collected continuously due to an accelerating field for the ions. The results highlighted how the cathode fall voltage limits the collection of the electron and ion parts of the probe current and how to handle the problem with a series battery in the probe circuit. In addition to the swept single-probe, a triple-probe was used simultaneously to compare and validate the results.

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GHz magnetron is used as pre-ionization source for plasma current startup. Different diagnostic systems like Rogowski coils, magnetic probes, flux loops, Langmuir probe, fast imaging and emission spectroscopy are installed on the device. The plasma temperature inside of GLAST, at the time of maxima of plasma current, is estimated by taking into account the Spitzer resistivity calculations with some experimentally determined plasma parameters. The plasma resistance is calculated by using Ohm's law with plasma current and loop voltage as experimentally determined inputs. The plasma resistivity is then determined by using length and area of the plasma column. Finally, the average plasma electron temperature is predicted to be 12.65eV for taking neon (Ne) as a working gas.

The stopping power and other transport coefficients have been calculated for ionized beams channeling through a crystal using a statistical method developed by Chnndrasckhar. Only the interaction of beam particles with conduction electrons, treated as a free gas, is considered. Unlike earlier investigations, also the effect on the test particles of encounters with faster field particles is considered. Two types of potentials have been used, a Debye and a Coulomb one. Both potentials give nearly the same results. It is found that the values of energy loss and transport coefficients increase with increasing energy of the incident beam. The stopping power is nearly the same as that obtained by earlier workers.Die Brenisenergie und andere Transportkoeffizienten werden fur ionisierte Strahlen, die durch einen Kristall kanalisieren, berechnet, wobei eine von Chandrasekhar entwickelte statistische Methode benutzt wird. E s wird nur die Wechsel wirkung von Strahlt,eilchen mit den als freies Elektronengns behandelten Leitungselektronen berucksiclitigt. I m Gegensat.z zu friiheren Untersuchungen wurde auch der EinfluB von StoBen der Testpartikel niit schnelleren Feldteilchen beriicksichtigt. Zwei Potentialtypen, Debye-und Coulonibpotentinl, wurden benutzt und geben nahezu dieselben Ergebnisse. Es wird gefunden, dnl3 die Energieverlustwerte und Transportkoeffizientn niit wnchsender Energie des einfallenden Strahls ansteigen. Die Bremsenergie ist nahezu dieselbe wie die von friiheren Aut.oren gefundene.