Evolution of molecular states studied in collisions of ions with laser excited atoms by a crossed beam experiment

Polarization effects in ionizing thermal energy collisions of laser-excited Ne(3p 3 D 3) atoms with Ar atoms

“…For intermediate distances R<9ao, these rotational couplings drop down by 30-50~, and the splitting in the 12p9, ~2) energy curves gives rise to a more rapid oscillation of the exponential function in (6) such that the population in BF varies more slowly. In our collision systems no locking radius [16,17,49] of the body-fixed population is seen. Even at the closest distance (R = b), where the ~2-splittings are largest, the (2-populations vary significantly 9…”

“…the dependence of observables on the polarization direction, constitutes a sensitive probe of the dynamic behaviour of the collision system. Clear polarization effects have been observed in differential rainbow scattering of Na(3p3/2 ) atoms [-7] and K(4p3/2 ) atoms [15] from Hg atoms and in superelastic [16] and inelastic [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] scattering of Na § ions from Na(3p3/2 ) atoms. In these cases, a narrow range of impact parameters in a well-defined collision plane is responsible for the polarization dependent intensity.…”

Coherence effects in low energy Na*(3p)+Na+ scattering: Experiment and semiclassical calculations

“…The crossed beam experiment has been described in detail before [5,6]. Briefly, an energy-selected Na + beam of an energy width better than AE(FWHM) = 150 meV is crossed with a sodium atom beam at right angles.…”

“…Aligned or oriented sodium Na*(3p) atoms are produced by optical pumping of the sodium atoms with polarized laser light. This method was employed previously in an investigation of the Na*(3p) + Na + --+Na(3s) + Na + deexcitation process [5,6]. There, we have applied simple 1 1983-84 visiting fellow Joint Institute for Laboratory Astrophysics Physics, University of Colorado and National Bureau of Standards models in order to describe the evolution of the space-fixed atomic states prepared by laser excitation at large internuclear distances into the bodyfixed molecular states.…”

“…In studies with left and right hand circularly polarized light the angular momentum transferred in the collision process has been determined. The results are compared with similar data for the 3p--,3s deexitation process studied previously [6].The density matrix of the Na*(3p) state has been evaluated with respect to the collisional excitation to Na*(3d). Semiclassical calculations based on the coupled channel impact parameter approximation using pseudopotentials [7] and nonadiabatic rotational coupling elements for the Na* system [12] have been performed.…”