The transition frequencies of the nS→nP and nD→(n+1)P sodium atom series were measured within the 53–350-GHz range for the main quantum number n=22–32. More precise values of ls splitting and quantum defects for ${\mathit{P}}_{1/2,3/2}$ and ${\mathit{D}}_{3/2,5/2}$ terms were determined. The frequencies were measured with an accuracy of better than 50 kHz. The results were treated using the Rydberg formula E(n,l,j)=-${\mathit{R}}_{\mathrm{Na}}$/(n-${\mathrm{\delta }}_{\mathit{n}\mathit{l}\mathit{j}}$${)}^2$. The quantum defect was calculated by using the expression ${\mathrm{\delta }}_{\mathit{n}\mathit{j}}$=${\mathrm{\varepsilon }}_{\mathit{l}\mathit{j}}$+${\mathrm{\alpha }}_{\mathit{l}\mathit{j}}$/${\mathit{n}}^{\mathrm{*}2}$. The constants ${\mathrm{\varepsilon }}_{\mathit{l}\mathit{j}}$ and ${\mathrm{\alpha }}_{\mathit{l}\mathit{j}}$ that result from this work are ${\mathrm{\varepsilon }}_{1/2}$=0.855 444 58(14), ${\mathrm{\alpha }}_{1/2}$=0.112 668 (90), ${\mathrm{\varepsilon }}_{3/2}$=0.854 625 83(12), and ${\mathit{a}}_{3/2}$=0.112 878(81) for the P term and ${\mathrm{\varepsilon }}_{3/2}$=0.014 909 19(38), ${\mathit{a}}_{3/2}$=-0.042 19(25), ${\mathrm{\varepsilon }}_{5/2}$=0.014 925 82(55), and ${\mathit{a}}_{5/2}$=-0.043 33(35) for the D term. The ls-splitting constants determined from the expression Δ${\nu }_{\mathit{l}}$=${\mathit{A}}_{\mathit{l}}$/${\mathit{n}}^{\mathrm{*}3}$ are ${\mathit{A}}_{\mathit{p}}$=5 384 790(420) MHz for the P term and ${\mathit{A}}_{\mathit{d}}$=97 340(680) MHz for the D term.

• Received 5 January 1995

DOI:https://doi.org/10.1103/PhysRevA.52.514