Cold-cathode ionization gauge

Gauges. Because there is no way to measure and/or distinguish molecular vacuum environment except in terms of its use, readings related to gas-phase concentration ate provided by diaphragm, McCleod, thermocouple, Pitani gauges, and hot and cold cathode ionization gauges (manometers). 

Coking steam coal grade (U.K.), 6 713t Coking tests, coal, 6 727, 755 Cola beverages, 6 366 Colchicine, 2 72, 74, 91 13 302 Cold-cathode ionization gauges,... 

Penniman-Zoph process, 19 400 Penning cold-cathode ionization gauges,... 

A precision aneroid manometer is used for measurements in the 760— 1 torr range. Thermocouple gauges are used in the 1 — 1 x 10 3 range. A cold cathode ionization gauge is used in the high vacuum range down to 10-6 torr. 

Cold Cathode Ionization Gauges, Journal Vacuum Science and Technology, A, 9, pp. 1977-1985 (1991). 

Pumping Speed Test Results. The pumping speed performance curves are shown in Fig. 3. The curves are for nitrogen and argon. Above 1 x 10 torr the speed curve is based on the (hot) ionization gauge. Below this pressure the (cold cathode) ionization gauge was... 

The cold cathode ionization gauge has offsetting advantages relative to the hot cathode type. It is insensitive to mechanical vibrations, is not susceptible to an inrush of air in the event of a vacuum accident (that can destroy the healed filament in the hot cathode type) and is less susceptible to harm from contaminants. 

Suto H, FujiiC. et al.. Fabrication of cold cathode ionization gauge using screen-printed carbon nanotube field electron emitter. Japanese Journal of Applied Physics, 2008.47(4) 2032-2035. 

Ionization and collection of ions - e.g. hot cathode ionization gauge cold cathode ionization gauge radioactive ionization source gauge. 

Cold cathode ionization gauge (vacuum technology) An ionization-type vacuum gauge where the electrons for ionization are usually produced by a secondary electron-emitting surface or a radioactive material. Often uses a magnetic field to increase the path length of the electrons. 

Cold-cathode ionization vacuum gauges (Penning vacuum gauges)... 

Thermocouple vxuum gauge Bimetallic vacuum gauge Thermistor vacuum gauge Cold-cathode ionization vacuum gauge... 

Fig. 7.10. Cutaway of a cold cathode (Penning) gauge. The wire anode (A) is connected through a ceramic insulator (i) to the high-voltage lead (H). Under the influence of the magnetic field created by M, the elcclrons travel a long spiral path between the body and the anode. The current, which arises from electrons and positive ions of the ionized gas molecules, is related to the pressure. The open end (C) is attached to the vacuum system.

In all those measurement instruments which use the ionization of gas molecules as the measurement principle (cold-cathode and hot-cathode ionization vacuum gauges), strong magnetic leakage fields or electrical potentials can have a major influence on the pressure indication. At low pressures it is also possible for wall potentials which deviate from the cathode potential to influence the ion trap current. 

Fig. 3. Pumping speed vs. pressure (A) pressure measurement using Bayard-Alpert ionization gauge (B) pressure measurement using cold cathode Redhead Magnetron gauge.

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