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Zero field level crossing in the helium atom Bardsley, Robert Eckardt
Abstract
Zero-field level crossing techniques have been used to measure some upper state lifetimes of the helium atom. The upper states of the atom were excited in a discharge between two capacitor plates. A radio frequency voltage was applied to these plates by a 450 MHz source. The emitted light was modulated by rotating a quarter-wave plate in front of a polaroid in the beam of emitted light. The polarization, which is directly related to this modulation, was measured by a phase sensitive lock-in amplifier. The halfwidths of curves obtained by plotting the polarization against the magnetic field strength for the n¹D - 2¹P transitions yielded lifetimes of; 2.71 x 10(-8) sec. for the 3¹D state, 3.97 x 10(-8) sec. for the 4¹D state and 4.48 x 10(-8) sec. for the 5¹D state.
Item Metadata
Title |
Zero field level crossing in the helium atom
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Creator | |
Publisher |
University of British Columbia
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Date Issued |
1970
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Description |
Zero-field level crossing techniques have been used to measure some upper state lifetimes of the helium atom. The upper states of the atom were excited in a discharge between two capacitor plates. A radio frequency voltage was applied to these plates by a 450 MHz source. The emitted light was modulated by rotating a quarter-wave plate in front of a polaroid in the beam of emitted light. The polarization, which is directly related to this modulation, was measured by a phase sensitive lock-in amplifier.
The halfwidths of curves obtained by plotting the polarization against the magnetic field strength for the n¹D - 2¹P transitions yielded lifetimes of; 2.71 x 10(-8) sec. for the 3¹D state, 3.97 x 10(-8) sec. for the 4¹D state and 4.48 x 10(-8) sec. for the 5¹D state.
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Genre | |
Type | |
Language |
eng
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Date Available |
2011-05-12
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Provider |
Vancouver : University of British Columbia Library
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Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
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DOI |
10.14288/1.0084812
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URI | |
Degree | |
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Affiliation | |
Degree Grantor |
University of British Columbia
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Campus | |
Scholarly Level |
Graduate
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Aggregated Source Repository |
DSpace
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Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.