EXPERIMENTAL MAPPING OF THE ABSOLUTE VALUE OF THE ELECTRONIC TRANSITION DIPOLE MOMENT FUNCTION $\mu_{e}(R)$ OF THE Na$_{2}$ $A^{1}\Sigma^{+}_{u}-X^{1}\Sigma^{+}_{g}$ SYSTEM

Author Institution: Physics Department, Temple University, Philadelphia, PA 19122; Physics Department, Lehigh University, Bethlehem, PA 18015; Physics Department, Temple University, Philadelphia, PA 19122\maketitle The absolute value of the transition dipole momentfunction $\mu_e(R)$ of the $A^{1}\Sigma^{+}_{u}-X^{1}\Sigma^{+}_{g}$ band of Na$_{2}$ was mapped experimentally within a relatively large range of internuclear distance R. The transition dipole moment matrix element of a set of rovibrational transitions between the $A^{1}\Sigma^{+}_{u}$ and $X^{1}\Sigma^{+}_{g}$ states was measured using the Autler-Townes (AT) effect}. By employing the R-centroid approximation, or a fit with a polynomial function involving the higher R-moments, $\mu_e$ as function of the internuclear distance was constructed. The AT effect based measurements give the absolute value of $\mu_e$ which can be used to "normalize" the transition dipole moment functions $\mu_e(R)$ obtained with other experimental techniques, such as line intensity based measurements, which in general give only the relative behavior of $\mu_e(R)$