Precision lifetime measurements using a variant of the collinear fast ion- laser-beam technique

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1993

OSTI ID:7270670

Jin, J

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. The test measurement on the Ar[sup +] rp[prime]2F[sup 0][sub 7/2] level produced the lifetime [tau] = 8.414 [+-] 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[sup +] 4p[prime][sub 1]F[sub 3], and the Ca[sup +] 4p[sup 2]P[sup 0][sub 1/2,3/2] levels, the author obtained [tau] = 11.17 [+-] 0.06 ns for the Cl[sup +] level, and [tau] 7.098 [+-] 0.020 ns and [tau] = 6.924 [+-] 0.019 ns for the J = 1/2 and 3/2 levels of Ca[sup +], respectively. Compared with previous less precise experimental results, good agreement has been found for the Ca[sup +] level lifetimes. The measured lifetimes for the Ar[sup +] and Ca[sup +] levels lie higher than all theoretical calculations by about 3%. In particular, the Ca[sup +] lifetime measurements provide an valuable experimental standard for current many body perturbation theory and multi-configuration Hartree-Fock theory calculations of lifetimes.

• Research Organization: Texas A and M Univ., College Station, TX (United States)
• OSTI ID: 7270670
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ARGON IONS
CALCIUM IONS
CHARGED PARTICLES
CHLORINE IONS
DATA
ENERGY LEVELS
EXCITED STATES
EXPERIMENTAL DATA
INFORMATION
IONS
LASER SPECTROSCOPY
LIFETIME
NUMERICAL DATA
SPECTROSCOPY