Enhanced sensitivity detectors for potential fluctuation measurements (abstract)

• Published in: Review of scientific instruments 1992-10, Vol.63 (10), p.4578-4578
• Main Authors: Keating, L. M., Schoch, P. M., Crowley, T. P., Schatz, J. G.
• Format: Article
• Language: English
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/1.1143673

A method to improve the sensitivity of energy analyzers is being developed for use with heavy ion beam probes (HIBP). The method basically involves segmenting a single entrance slit into ten slits and modifying a detector. Theory and a simplified test shows that a factor of 10 improvement in sensitivity is possible. Previously, potential fluctuation measurements would have a signal to noise factor of unity when the rms fluctuation equaled 10−5×V acc where V acc is the accelerator voltage. The new 2‐MeV HIBP on TEXT would be limited to potential fluctuations of greater than 20 Vrms when operating at full voltage. Measurements with the old system indicated that central potential fluctuations on TEXT were the order of 10 Vrms. The new detector should be able to measure down to 2 Vrms. A simplified geometry has been tested and showed a sensitivity as predicted, though a somewhat reduced range of operation. A test in an analyzer is planned. This work was supported by the U.S. Department of Energy.