Photoassociative spectroscopy as a self-sufficient tool for the determination of the Cs triplet scattering length

In photoassociation spectroscopy, the line intensities of a given vibration al progression exhibit zero-signal modulation reflecting the node structure of the s-wave ground state wave function of two free colliding atoms. This leads to the determination of the scattering length. We performed photoass ociation of cold Cs atoms: polarized in the Zeeman sublevel f = 4, m(f) = 4 . We analyzed the intensities of the lines associated with the Cs-2 0(g)(-) State dissociating to the 6s(1/2) + 6p(3/2) asymptote. This yields a value of the Cs triplet state scattering length, a(T) = -530a(0), while consiste ncy requirements impose a value of the multipole ground state molecular coe fficient, C-6 = 6510 a.u.