B\,¹Sigma⁺_(u) and EF\,¹Sigma⁺_(g) level energies of D₂

Accurate absolute level energies of the $B\,^1\Sigma^{+}_{u}$, $v=0-8, N$ and $EF\,^{1}\Sigma^{+}_{g}$, $v=0-21, N$ rovibrational quantum states of molecular deuterium are derived by combining results from a Doppler-free two-photon laser excitation study on several lines in the $EF\,{}^{1}\Sigma_{g}^{+}-X\,{}^{1}\Sigma_{g}^{+}$ (0,0) band, with results from a Fourier-transform spectroscopic emission study on a low-pressure hydrogen discharge. Level energy uncertainties as low as 0.0005 cm$^{-1}$ are obtained for some low-lying $E\,^{1}\Sigma^{+}_{g}$ inner-well rovibrational levels, while uncertainties for higher-lying rovibrational levels and those of the $F\,^{1}\Sigma^{+}_{g}$ outer-well states are nominally 0.005 cm$^{-1}$. Level energies of $B\,^1\Sigma^{+}_{u}$ rovibrational levels, for $v \leq 8$ and $N \leq 10$ are determined at an accuracy of 0.001 cm$^{-1}$. Computed wavelengths of D$_2$ Lyman transitions in the $B\,^1\Sigma^{+}_{u}-X\,^{1}\Sigma^{+}_{g}$ ($v,0$) bands are also tabulated for future applications.