Dynamics of metastable states in supersonic beams

Roberto Cristiano, Luigi Frunzio, Yurii N. Ovchinnikov +1 more

J. A. Haberman, Bruce E. Wilcomb, F. J. Van Itallie +1 more

A nitrogen-seeded supersonic nozzle-beam source of metastable mercury, Hg(6 3P0),isdescribed.Ground-state(6 1S0)mercuryisexcited with 2537 Å resonance radiation to the 6 3P1 state, which is then converted via intramultiplet quenching to the 6 3P0 state collision with nitrogen (the carrier gas). The mercury beam is accelerated by the N2 seeding gas to a speed of 8×104 cm sec−1. Thus, the present source provides a beam of a single metastable state, Hg(6 3P0), with 4.67 eV of electronic excitation and 0.67 eV of translational energy. The metastable beam has been characterized and the kinetics of the over-all photoexcitation and quenching process studied by a secondary electron (Auger) detector utilizing a potassium surface, and an electron-bombardment ionizer, mass-filter detector. Hg(6 3P0) beam intensities of 4×1012 atoms sr−1⋅sec−1 are obtained, based upon an (assumed) 5% efficiency for the Auger detector.

Matthew J. Partlow, Joerg Bochmann, X. Miao +1 more

Katrin Dulitz, Jutta Toscano, Atreju Tauschinsky +1 more

In a proof-of-principle experiment, we show that the longitudinal velocity of a supersonic beam of nitrogen atoms in the metastable 2 D state can be decreased from 460 to 410 m s −1 using a 12-stage Zeeman decelerator. The experimental results are in good agreement with three-dimensional numerical particle trajectory simulations. The generation of velocity-tunable supersonic beams of metastable nitrogen atoms opens new avenues for the study of chemical reactions at millikelvin temperatures.

João Victor Boechat Gomide, G. A. Garcia, Flávio C. Cruz +4 more

J.‐C. Karam, Jules Grucker, M. Boustimi +8 more

A method for obtaining a metastable atom beam with properties near to those of a ground state supersonic beam is demonstrated. Calculations on m sublevels of metastable argon near a metal surface are then presented.