Ionization in a dusty gas

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:346889

Rosenberg, M ^[1]

---

1. Univ. of California, San Diego, La Jolla, CA (United States). Dept. of Electrical and Computer Engineering

Dust grains can be charged positively by electron emission processes such as photoemission, thermionic emission, or secondary electron emission. Recently a theoretical scheme for forming a Coulomb lattice of positively charged dust grains in a high-pressure gas has been discussed. In that scheme, the grains are charged positively by the emission of photo-electrons in the presence of a flux of ultraviolet (UV) photons with energy larger than the work function of the grain, but lower than the ionization potential of the gas. The authors extend that theoretical analysis to explore grain charging processes such as photoemission or thermionic emission as a source of ionization (electrons) in a gas. In the simplest case of an inert gas, the electron density generated may be determined by balancing the electron emission from the grains with the electron loss processes involving recombination onto the grains. Some example regimes of dust, gas, and photon flux parameters are investigated. Aspects of basic physics issues relevant to these dust ionization processes are also explored, including the effect of grain size and background gas parameters on the electron emission process, and the heating and cooling of small grains via radiation or conduction.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• OSTI ID: 346889
• Report Number(s): CONF-980601--
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DUSTS
ELECTRIC CHARGES
ELECTRON EMISSION
IONIZATION
PARTICLE SIZE
PLASMA
ULTRAVIOLET RADIATION