Excited krypton and mercury density measurements in an rf capacitive discharge

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:51808

Michael, J D ^[1]

---

1. GE Lighting, Cleveland, OH (United States)

A capacitive discharge is created in a cylindrical quartz container placed between a pair of circular planar electrodes. The buffer gas is krypton, while the Hg vapor pressure can be controlled by changing the temperature of the cold finger. At low power ({le} 10W), the axial and radial profiles of the excited Kr (5s {sup 3}P{sub 1}) and Hg (6 {sup 3}P{sub 1}) states are obtained by standard Laser Induced Fluorescence (LIF) techniques. Off-Resonance Raman Scattering (ORRS) is used at higher power ({ge} 20W) and Hg vapor pressure ({ge} 6mTorr) to obtain the Hg (6 {sup 3}P{sub 1}) state. This Raman method, which uses a detuned pump laser beam (10--20 cm{sup {minus}1} from resonance), was chosen rather than LIF under these conditions to avoid any self absorption of the induced fluorescence signal. Axial and radial density profiles of the Kr and Hg resonance states are obtained at various power levels and varying Hg vapor pressures. For the particular case of signals obtained using ORRS, a calibration H{sub 2} cell is used to obtain absolute number densities of the Hg resonance state.

• OSTI ID: 51808
• Report Number(s): CONF-940604--; ISBN 0-7803-2006-9
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
DESIGN
ELECTRIC DISCHARGES
EXCITED STATES
KRYPTON
LASER RADIATION
LIGHTING SYSTEMS
MERCURY
RAMAN EFFECT