Measurement of the electron impact photoemission cross sections of the 92. 0 nm and 93. 2 nm emission lines of argon II for the vuv radiometric project

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5173684

McPherson, Jr, L A

Measurements of the electron impact photoemission cross sections for 92.0 nm and 93.2 nm radiation from Ar II were made. The unpolarized radiation is produced by transitions from the 3s3p/sup 6/ /sup 2/S/sub 1/2/ state to the 3s/sup 2/3p/sup 52/P/sub 1/2'3/2/ states. The cross sections were determined at an incident electron energy of 100 eV and found to be (5.81 +/- 0.48) x 10/sup -18/ cm/sup 2/ for the 92.0 nm line (S/sub 1/2/ ..-->.. P/sub 3/2/) and (3.00 +/- 0.25) x 10/sup -18/ cm/sup 2/ for the 93.2 nm line (S/sub 1/2/ ..-->.. P/sub 1/2/). The Ar II photoemission cross sections will be part of an atlas of electron impact photoemission cross sections for emission lines throughout the vuv wavelength region. This atlas will form the basis of a new portable primary vuv radiometric standard. The new intensity standard consists of an electron beam used to excite gas atoms which subsequently emit characteristic line radiation. The absolute photon flux emitted in an emission line can be determined if the electron impact photoemission cross section for the emission line is known, along with the target gas density and the electron beam current. The absolute radiometric standard can be used to determine the detection efficiency of any uncalibrated spectrometer-detector system.

• Research Organization: North Carolina State Univ., Raleigh (USA)
• OSTI ID: 5173684
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON IONS
CATIONS
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELECTROMAGNETIC RADIATION
ELECTRON COLLISIONS
EMISSION
ENERGY RANGE
EV RANGE
EV RANGE 10-100
FAR ULTRAVIOLET RADIATION
IONS
MEASURING INSTRUMENTS
PHOTON EMISSION
RADIATION DETECTORS
RADIATIONS
RADIOMETERS
STANDARDS
ULTRAVIOLET RADIATION