Pulsed electron-beam-sustained discharge in oxygen-containing gas mixtures: electrical characteristics, spectroscopy,and singlet oxygen yield

Journal Article · Thu Sep 30 00:00:00 EDT 2004 · Quantum Electronics (Woodbury, N.Y.)

DOI:https://doi.org/10.1070/QE2004V034N09ABEH002883· OSTI ID:21470598

Vagin, Nikolai P; Ionin, Andrei A; Klimachev, Yu M; Kotkov, A A; Podmar'kov, Yu P; Seleznev, L V; Sinitsyn, D V; Frolov, M P; Yuryshev, Nikolai N ^[1]; Kochetov, Igor' V; Napartovich, A P ^[2]; Hager, G D ^[3]

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1. P.N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)
2. State Research Center of Russian Federation 'Troitsk Institute for Innovation and Fusion Research', Troitsk, Moscow Region (Russian Federation)
3. Air Force Research Laboratory, Albuquerque, NM (United States)

The electrical and spectroscopic characteristics of electron-beam-sustained discharge (EBSD) in oxygen and oxygen-containing gas mixtures are studied experimentally under gas pressures up to 100 Torr in a large excitation volume ({approx}18 L). It is shown that the EBSD in pure oxygen and its mixtures with inert gases is unstable and is characterised by a small specific energy contribution. The addition of small amounts ({approx}1%-10%) of carbon monoxide or hydrogen to oxygen or its mixtures with inert gases considerably improves the stability of the discharge, while the specific energy contribution W increases by more then an order of magnitude, achieving {approx}6.5 kJ L{sup -1} atm{sup -1} per molecular component of the gas mixture. A part of the energy supplied to the EBSD is spent to excite vibrational levels of molecular additives. This was demonstrated experimentally by the initiation of a CO laser based on the O{sub 2} : Ar : CO = 1 : 1 : 0.1 mixture. Experimental results on spectroscopy of the excited electronic states O{sub 2}(a{sup 1{Delta}}{sub g}) and O{sub 2}(b{sup 1{Sigma}}{sub g}{sup +}), of oxygen formed in the EBSD are presented. A technique was worked out for measuring the concentration of singlet oxygen in the O{sub 2}(a{sup 1{Delta}}{sub g}) state in the afterglow of the pulsed EBSD by comparing with the radiation intensity of singlet oxygen of a given concentration produced in a chemical generator. Preliminary measurements of the singlet-oxygen yield in the EBSD show that its value {approx}3% for W {approx} 1.0 kJ L{sup -1} atm{sup -1} is in agreement with the theoretical estimate. Theoretical calculations performed for W {approx} 6.5 kJ L{sup -1} atm{sup -1} at a fixed temperature show that the singlet-oxygen yield may be {approx}20%, which is higher than the value required to achieve the lasing threshold in an oxygen-iodine laser at room temperature. (laser applications and other topics in quantum electronics)

• OSTI ID: 21470598
• Journal Information: Quantum Electronics (Woodbury, N.Y.), Vol. 34, Issue 9; Other Information: DOI: 10.1070/QE2004v034n09ABEH002883; ISSN 1063-7818
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
AFTERGLOW
BACKSCATTERING
CARBON MONOXIDE
ELECTRON BEAMS
EXCITATION
GAS LASERS
GLOW DISCHARGES
HYDROGEN
IODINE
MIXTURES
OXYGEN
RARE GASES
SPECTROSCOPY
STABILITY
TEMPERATURE RANGE 0273-0400 K
BEAMS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
DISPERSIONS
ELECTRIC DISCHARGES
ELEMENTS
ENERGY-LEVEL TRANSITIONS
FLUIDS
GASES
HALOGENS
LASERS
LEPTON BEAMS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PARTICLE BEAMS
SCATTERING
TEMPERATURE RANGE