Penning discharge

Penmman-Zoph process Penning discharge Penning gauge Penning ionization... 

The formation of ions is a consequence of either a discharge at a high electric field strength (so-called cold-cathode or Penning discharge, see... 

As indicated in Chapter 4, sputter ion pumps are based on sorption processes initiated by gas ions formed in a Penning discharge and SIPs achieve their high pumping speed by incorporating many individual Penning cells. 

Figure 4-28. Classical Penning discharge with uniform magnetic induction and electrostatic trapping of electrons general schematic, distribution of electrostatic potential, and magnetie field along the diseharge axis.

H. Baumann, K. Bethge, and E. Heinicke, Production of negative lithium ions in a Penning discharge, Nucl. Instr. Methods 46, 43-44 (1967). 

By working principle, they can be classified as hot filament sources, ion sources based on Penning discharge (PIG), radio frequency (RF) and microwave (MW) ion sources, electron cyclotron resonance (ECR) ion sources, electron beam ion sources (EBIS, EBIT), laser ion sources, cusp and multicusp ion sources, sputtering ion sources. 

The effective cross section s for ionizing collisions depends on the type of gas. According to (2.25), the discharge current i is a function of the number particle density ng, as in a Penning gauge, and it can be used as a measure of the pressure in the range from 10 to 10 mbar. At lower pressures the measurements are not reproducible due to interferences from field emission effects. 

In a second experiment, Ayers and Stahl studied the effects of discharging a CS pen-gun cartridge into a rabbit eye at a distance of 20 cm. At that distance, the wad caused less damage than the blast and the particles of CS. Only three of 10 animals suffered severe eye lesions, which appeared to combine mechanical damage (lacerations) from the wad and conjunctivitis, intraocular hemorrhage, keratitis, and corneal edema probably from the blast and CS particles driven into the eye. The other animals showed only mild conjunctivitis, which cleared after 3 d. 

CN may cause primary irritant dermatitis or allergic contact dermatitis by delayed hypersensitivity. After sensitization, acute exposure to CN causes itching, erythema, edema, vesiculation, purpura, and necrosis.28 Jolly and Carpenter reported that an accidental discharge of a pen gun resulted in erythema and edema 24 h later the patient had been exposed to CN 5 yr earlier. Queen and Stander reported severe reactions to CN 17 yr after a first exposure to the agent. 

Glow discharge ion source in Ar plasma Penning and e ionization plasma 3000-6000 ne 1015 cm-3 M+ low pressure double-focusing SFMS (reverse Nier-Johnson) traces, high-purity metals... 

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