Hyperfine splitting and isotope-shift measurements within the 378-nm6P1/2−7S1/2

Abstract

Using a frequency-doubled diode laser system, we have measured the hyperfine splitting in the (6s 2 7s)7S 1/2 excited state of the two naturally occurring thallium isotopes. For 205 Tl and 203 Tl we find frequency intervals of 12294.5͑1.5͒ and 12180.5͑1.8͒ MHz, respectively. This measurement addresses an earlier discrepancy in measured values for these intervals. At the same time, we have measured, with a factor of 50 improved precision, the 205 Tl-203 Tl isotope shift within the 378-nm 6 P 1/2 -7S 1/2 transition.

Measurement of7p1/2-state hyperfine structure and7s1/2-Ranjit1, Kealhofer2, Vukasin3 et al. 2014Phys. Rev. ASelf Cite

“…where H 7s,203 and H 7s,205 are the previously measured hyperfine splittings in the 7s 1/2 states in 203 Tl and 205 Tl isotopes respectively [4,17]. The small uncertainty in these measured 7s 1/2 HFS splittings does not significantly increase the overall measurement error in our isotope shift determination.…”

“…In the trivalent thallium atomic system, new calculational techniques make use of a hybrid method combining perturbative features with a configuration interaction approach to address valence electron correlations [1,2]. In our research program, using both vapor cell and atomic beam spectroscopy techniques, we have completed a series of experimental atomic structure measurements in thallium [3][4][5], which are in excellent agreement with these recent calculations [6,7]. When such atomic theory calculations are combined with an experimental parity nonconservation (PNC) measurement in thallium [8,9] the combination provides an important test of standard-model electroweak physics.…”

“…A subset of these measurements were later corrected due to self-reported 'calibration and linearization errors' [16]. More recently, two measurements of the 7s 1/2 -state HFS, first by our group in 2000 [4], and then by Chen et al in 2012 [17] have confirmed the inaccuracy of the original set of measurements from the Giessen group. In the present paper, we report new measurements of the 7p 1/2 excited-state HFS in the two naturally occurring isotopes of thallium.…”

Calculation of Thallium Hyperfine Anomaly

“…Using expression (6) for two different nuclear radii we can calculate charge correction to atomic HFS, while using expression (5) we simultaneously account for charge and magnetic corrections.…”

“…Below we discuss how to calculate hyperfine anomaly for many-electron atoms with available atomic packages. We use thallium atom as reference system for our calculations, because for this atom there are comprehensive experimental data [5][6][7][8][9] and many theoretical calculations [4,[10][11][12][13].…”