Method of determining the x-ray limit of an ion gauge

Patent · Thu Jan 01 04:00:00 EST 1981

OSTI ID:864056

Lanni, Christopher P ^[1]

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1. Shirley, NY

An ion gauge having a reduced "x-ray limit" and means for measuring that limit. The gauge comprises an ion gauge of the Bayard-Alpert type having a short collector and having means for varying the grid-collector voltage. The "x-ray limit" (i.e. the collector current resulting from x-rays striking the collector) may then be determined by the formula: ##EQU1## where: I.sub.x ="x-ray limit", I.sub.l and I.sub.h =the collector current at the lower and higher grid voltage respectively; and, .alpha.=the ratio of the collector current due to positive ions at the higher voltage to that at the lower voltage.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY
• DOE Contract Number: EY-76-C-02-0016
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4302679
• OSTI ID: 864056
• Country of Publication: United States
• Language: English

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