Argon and argon-oxygen glow discharge cleaning of the Main Ring beam pipe

Technical Report · Wed Feb 15 00:00:00 EST 1989

DOI:https://doi.org/10.2172/6080884· OSTI ID:6080884

Trbojevic, D; Pastore, N

This report presents the experimental results from the argon and argon-oxygen gas mixture glow discharge in the Main Ring beam pipe and is a follow-up to the proposal for vacuum improvements of the Main Ring magnets and straight sections and the warm Tevatron straight sections. Glow discharge was used in the experiment in order to clean the vacuum system instead of bakeout which could only be performed with great difficulty or not at all. It is a relatively simple and very effective method. The glow discharge occurs under specific gas pressures (10--120 mTorr) and current flows (10/sup /minus/5/ /minus/ 10/sup /minus/1/ A) through gas excitation and formation of plasma conditions. Deexcitation of the gas molecules produces visible light. Several mechanisms have been proposed to explain the glow discharge cleaning process. Ions can sputter adsorbed molecules or atoms at the cathode surface and even produce lattice damage extending several monolayers below the surface. The glow discharge has already been extensively used for vacuum improvements in accelerators. 9 refs.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 6080884
• Report Number(s): FNAL-TM-1566; ON: DE89011491
• Resource Relation: Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
FERMILAB TEVATRON
VACUUM SYSTEMS
SURFACE CLEANING
ARGON
GLOW DISCHARGES
MASS SPECTROMETERS
ACCELERATORS
CLEANING
CYCLIC ACCELERATORS
ELECTRIC DISCHARGES
ELEMENTS
FLUIDS
GASES
MEASURING INSTRUMENTS
NONMETALS
RARE GASES
SPECTROMETERS
SURFACE FINISHING
SYNCHROTRONS
430300* - Particle Accelerators- Auxiliaries & Components