[@BGR91]

  : Comparison of measurements of hyperfine intervals in the $5P_{3/2}$ state of $^{87}$Rb to previous results. The last row is calculated from the $A$ and $B$ coefficients reported therein. All values in MHz.

\[t1\]

Measurements in the $5P_{3/2}$ state of $^{85}$Rb
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With the reliability of the technique established with measurements in $^{87}$Rb, we turned to the other isotope, namely $^{85}$Rb. The probe was locked to the $F=3
\rightarrow F'=4$ transition, and the pump was scanned either across the $F=3 \rightarrow F'=3$ transition or the $F=3 \rightarrow F'=2$ transition. Typical spectra for the two cases are shown in Fig. \[rb33\]. As before, Lorentzian fits to the measured spectra were used to determine the peak center, and thus the $\{ 4-3 \}$ and $\{
3-2 \}$ intervals.

\(a) (b)

The average values for the two intervals are listed in Table \[t2\]. For the $\{ 4-3 \}$ interval, the standard deviation from a set of 14 measurements is 35 kHz. For the $\{ 3-2 \}$ interval, the standard deviation from 11 measurements is 34 kHz. These values are also compared to other values in the literature. There are two non-overlapping sets for the $\{ 4-3 \}$ interval. The value from Ref. 