https://doi.org/10.1140/epjd/e2003-00221-7
Observation of the long-range potential well of the (6)1Σg+(3s+5s) state of Na2
1
Institut für Quantenoptik, Universität Hannover, Welfengarten
1, 30167 Hannover, Germany
2
Laboratoire Aimé Cotton, CNRS, Campus
d'Orsay, Bâtiment 505, 91405 Orsay Cedex, France
Corresponding authors: a dulieu@lac.u-psud.fr - b tiemann@iqo.uni-hannover.de
Received:
5
March
2003
Published online:
22
July
2003
We report on the first observation of the outer well of the 
state of Na2 molecule. The levels are
populated in a molecular beam experiment with a three step laser excitation. The
fact that these levels
predissociate allows an almost background free detection by the appearance of
atomic fluorescence. With this
method almost all vibrational levels of the outer well are observed. The
corresponding predissociation line
widths show an oscillating behaviour. The theoretical description of the
predissociation is presented in the framework of
mapped Fourier grid Hamiltonian representation with optical potential, involving
two coupled electronic states. Combining the
spectroscopic information on energy positions and predissociation widths, a
Rydberg-Klein-Rees potential curve is given for
the outer well. Such a state could offer a reliable path for photoassociation of
cold Na atoms and
formation of ultracold Na2 molecules.
PACS: 33.80.Gj – Diffuse spectra; predissociation, photodissociation / 31.50.Gh – Surface crossings, non-adiabatic couplings / 42.62.Fi – Laser spectroscopy
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003
