Broadening of alkali lines by atomic hydrogen

J. F. Babb, K. Kirby, H. K. Chung

Derek N. Stacey, J. Cooper

Andrei Derevianko, Robin Côté, Michael J. Jamieson +3 more

Qiang Liu, Zeng Xianjin, Jun-Hai Zhang +2 more

The buffer gas of alkali metal atom vapor cell will affect the alkali atom polarization and spectral line broadening.The method of making a Cs cell containing helium buffer gas is introduced.The pressure broadening of the Cs D2(852 nm) line with the buffer gas is measured using atomic saturated absorption spectrum.The pressure value would be obtained through analyzing absorption linewidth and broadening factors.

Mladen Movre, Goran Pichler

Adiabatic potential curves were calculated using perturbation theory for the long-range electrostatic interaction between two alkali atoms of the same species, one being in the ground state, the other in the resonance-excited state. Comparison with recent experiments showed that the observed satellites and asymmetries in the self-broadened quasi-state wings of the alkali resonance lines are the consequence of extrema in certain potential curves between the fine-structure levels.

E. W. Weber

Accurate values for the density shift and broadening of five isolated ${\mathrm{H}}_{\ensuremath{\alpha}}$ fine-structure transitions have been measured. Doppler-free polarization and double-quantum saturation spectroscopy with a cw dye laser are used in a He dc discharge with 1% ${\mathrm{H}}_{2}$. The negative shifts and the huge broadening values are correctly predicted by an impact-approximation theory taking into account the large cross sections for fine-structure transfer (quenching) collisions and only Van der Waals interaction between ${\mathrm{H}}^{*}$ and He. Consequences of a comparison with the positive shift of the unresolved ${\mathrm{H}}_{\ensuremath{\alpha}}$ line and of the alkali-metal $D$ lines in He buffer gas are discussed. For pressures below 0.1 Torr hfs decoupling collisions give rise to a positive shift of single ${\mathrm{H}}_{\ensuremath{\alpha}}$ fine-structure lines and to a collisional narrowing effect analogous to that observed in nuclear magnetic resonance.