Electron Multiplier for the Measurement of an Ion Current on a Mass Spectrometer; MULTIPLICATEUR D'ELECTRONS POUR LA MESURE DE COURANTS D'IONS SUR UN SPECTROMETRE DE MASSE

Technical Report · Sun Sep 01 00:00:00 EDT 1957

OSTI ID:4317357

Lobez, P; Nief, G

The apparatus described is designed to measure weak ion currents received at the collector of a mass spectrometer. The report describes successively the study of electron paths in the multiplier by the method of analogy, using rubber membranes, and the practical details of construction of the apparatus. The variation with surface treatment of the secondary emission coefficient of the alloy CuBe containing 2 per cent Be, which makes up the dynodes, and the influence of the vultage on the gain per stage, are discussed. Results of tests regarding: the influence of the ion mass on the gain, the background of the instrument, and the energy distribution of the impulses coming out on a high gain multiplier (q.q. 10/sup 7/) are given. Finally the performances of the multiplier are reported. For a low gain (10/sup 4/), precision and reproducibility comparable to the electrometer valve, sensitivity 100 times greater, currents capable of detection 10/sup -17/ ampere are obtained. For a high gain (10/sup 7/) and measurement by impulse counting, currents capable of detection 10/sup -19/ ampere are obtained. (auth)

• Research Organization: France. Commissariat a l'Energie Atomique, Paris
• NSA Number: NSA-12-009300
• OSTI ID: 4317357
• Report Number(s): CEA-692
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-58
• Country of Publication: France
• Language: English

Related Subjects

PHYSICS
ANALOG SYSTEMS
BACKGROUND
BERYLLIUM ALLOYS
COPPER ALLOYS
CURRENTS
DETECTION
DISTRIBUTION
EFFICIENCY
ELECTRIC FIELDS
ELECTRODES
ELECTROMETERS
ELECTRON BEAMS
ELECTRONS
EMISSION
ENERGY
IONS
ISOTOPE EFFECTS
MASS SPECTROMETERS
MEMBRANES
OPTICAL SYSTEMS
PERFORMANCE
PHOTOMULTIPLIERS
PLANNING
PULSES
RUBBER
SENSITIVITY
STABILITY
SURFACES
VARIATIONS