Precision lifetime measurements using a variant of the collinear fast ion- laser-beam technique /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1993.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | A variant of the collinear fast ion-beam laser-beam spectroscopy technique for measuring ionic excited level lifetimes has been tested, and used to measure the lifetimes of several levels. This technique requires no mechanical motion or laser frequency sweeping. The Rapid Doppler Switching (RDS) technique used in the present work has been thoroughly described, and all significant error sources have been discussed in detail. Our test measurement on the Ar+ 4p'2F^0[7/2] level produced the lifetime τ = 8.414 [plus or minus] 0.025 ns, in excellent agreement with an earlier measurement with comparable precision. This demonstrated that the RDS technique can produce lifetime measurements accurate to 0.3%. Applying this technique to transitions from the Cl+4p'F[3], and the Ca+4p^2P^0[1/2,3/2] levels, we obtained τ = 11.17 [plus or minus] 0.06 ns for the Cl+ level, and τ = 7.098 [plus or minus] 0.020 ns and τ = 6.924 [plus or minus] 0.019 ns for the J = 1/2 and 3/2 levels of Ca+, respectively. Compared with previous less precise experimental results, good agreement has been found for the Ca+ level lifetimes. The measured lifetimes for the Ar+ and Ca+ levels lie higher than all theoretical calculations by about 3%. In particular, the Ca+ lifetime measurements provide a valuable experimental standard for current many body perturbation theory and multi-configuration Hartree-Fock theory calculations of lifetimes. |
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| Item Description: | Vita. "Major subject: Physics." |
| Physical Description: | vii, 72 leaves : illustrations ; 28 cm |
| Bibliography: | Includes bibliographical references. |