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Title: Measuring the Density of a Molecular Cluster Injector via Visible Emission from an Electron Beam

Technical Report ·
DOI:https://doi.org/10.2172/984347· OSTI ID:984347

A method to measure the density distribution of a dense hydrogen gas jet is pre- sented. A Mach 5.5 nozzle is cooled to 80K to form a flow capable of molecular cluster formation. A 250V, 10mA electron beam collides with the jet and produces Hα emission that is viewed by a fast camera. The high density of the jet, several 1016cm-3, results in substantial electron depletion, which attenuates the Hα emission. The attenuated emission measurement, combined with a simplified electron-molecule collision model, allows us to determine the molecular density profile via a simple iterative calculation.

Research Organization:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
DOE Contract Number:
DE-ACO2-09CH11466
OSTI ID:
984347
Report Number(s):
PPPL-4530; TRN: US1006429
Country of Publication:
United States
Language:
English