laser data.

The parallel ladders of $e$- and $f$-parity $J$-levels of [A$^1\Pi$]{}$(0)$ are nondegenerate because of the influence of perturbing $\Sigma$ states. The laser-measured $S$ and $Q$-branch lines provide information on $e$-parity [A$^1\Pi$]{}$(0)$ levels, while the $P$ and $R$ branches provide information on the $f$-parity components. Whereas, under the selection rules of one-photon absorption and emission, $R$ and $P$-branch lines probe $e$-parity levels, and the Q-branch lines probes $f$-parity components. The [e$^3\Sigma^-$]{}(1) and [d$^3\!\Delta$]{}(4) levels are split into $F_1$, $F_2$, and $F_3$; and $e$- and $f$-parity levels, not all of which were accessed in our experiments.

[l@r@r@r]{}

\
Constant & A$^1\Pi (v=0)$ & B$^1\Sigma^+ (v=0)$ & D$^1\!\Delta (v=0)$\
\
$T_v$ &$ 64753.3690(8)       $ &$ 86916.808(2){}^{\rm a}         $ &$ 65434.7557{}^{\rm b}$\
$B$ &$ 1.533674(5)         $ &$ 1.862475(5){}^{\rm a}          $ &$ 1.19331{}^{\rm b}   $\
$q$ $\times 10^{5}$ &$ 5.9(3)              $ &$                      $ &$                     $\
$D$ $\times 10^{6}$ &$ 6.743(3)            $ &$ 6.114(2){}^{\rm a}             $ &$ 6.43{}^{\rm b}      $\
$H$ $\times 10^{12}$ &$ -12{}^{\rm b}       $ &$ -9(3){}^{\rm a}         $ &$ -0.26{}^{\rm b}     $\
$\xi$ &$                     $ &$                      $ &$ -0.0256(9)          $\
\
Constant & e$^3\Sigma^- (v=0)$ & d$^3\!\Delta (v=3)$ & a$'^3\Sigma^+ (v=8)$\
\
$T_v$ &$ 63716.208{}^{\rm b} $ &$ 63955.0056{}^{\rm b} $ 