Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Associative ionization in collisions between Na(3 P3/2 ) and Cs(6 P3/2 )

C. Gabbanini, M. Biagini, Silvia Gozzini, A. Lucchesini, L. Moi

Published Mar 1, 1991• 6 citations
Publisher

Abstract

The results of an experiment on the associative ionization collision between sodium and cesium excited atoms are reported. The atoms are excited by two resonant cw lasers to the 3${\mathit{P}}_{3/2}$ and 6${\mathit{P}}_{3/2}$ levels, respectively, and the formation of the ${\mathrm{NaCs}}^{+}$ molecular ion is observed. The rate constant of such process has been measured relative to the known rate constant of sodium associative ionization and its value resulted in K=(5.4\ifmmode\pm\else\textpm\fi{}3.2)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}11}$ ${\mathrm{cm}}^{3}$ ${\mathrm{s}}^{\mathrm{\ensuremath{-}}1}$.

DOI
10.1103/physreva.43.2311

Related papers

Collisional and thermal ionization of sodium Rydberg atoms: I. Experiment fornS andnD atoms withn= 8–20

I. I. Ryabtsev, Denis B. Tretyakov, Ilya I. Beterov +3 more

Collisional and thermal ionization of sodium n S and n D Rydberg atoms with n = 8–20 has been studied. The experiments were performed using a two-step pulsed laser excitation in an effusive atomic beam at atom density of about 2 × 10 10 cm −3 . Molecular and atomic ions from associative, Penning and thermal ionization processes were detected. It was found that the atomic ions were created mainly due to photoionization of Rydberg atoms by photons of blackbody radiation at the ambient temperature of 300 K. Blackbody ionization rates and effective lifetimes of Rydberg states of interest were determined. The molecular ions were found to be from associative ionization in Na( nL ) + Na(3S) collisions. Rate constants of associative ionization have been measured using an original method based on relative measurements of Na + 2 and Na + ion signals.

arXiv:physics/0501088•Journal of Physics B Atomic Molecular and Optical Physics•Jan 6, 2005•23 citations

Ultracold photoassociative ionization collisions in an atomic beam: Optical field intensity and polarization dependence of the rate constant

Chun-Cheng Tsao, Reginaldo de Jesus Napolitano, Yang Wang +1 more

We report here measurements of two-body photoassociative ionization collisions between sodium atoms within an ultranarrow velocity class selected from a well-collimated, thermal atomic beam. Doppler-shifted excitation of the Na(3s${\mathrm{}}^{2}$${\mathit{S}}_{1/2}$;F=1)\ensuremath{\rightarrow}Na(5p${\mathrm{}}^{2}$${\mathit{P}}_{3/2}$) transition at 285 nm by a single-mode laser defines the narrow velocity class that subsequently populates the F=2 hyperfine level of the Na ground state by optical pumping. Probe laser beam excitation tuned near the Na(3s${\mathrm{}}^{2}$${\mathit{S}}_{1/2}$;F=2)\ensuremath{\rightarrow}Na(3p${\mathrm{}}^{2}$${\mathit{P}}_{3/2}$;F=3) transition produced photoassociative ionization with an average collision energy ${\mathit{E}}_{\mathit{K}}$ corresponding to a temperature of 5.3 mK (${\mathit{E}}_{\mathit{K}}$=3/2kT). We determine the rate constant for the process as a function of probe beam intensity and polarization.

Physical Review A•Jan 1, 1995•11 citations

Na-Cs Hornbeck-Molnar ionization

C. Gabbanini, M Biagini, Silvia Gozzini +2 more

An investigation of the 'Hornbeck-Molnar ionization' process between laser-excited Cs and ground state Na atoms has been performed in a crossed beam apparatus. Caesium atoms in the 8d, 10s, 9d, 11s and 10d levels respectively have been obtained by two-step resonant CW laser excitation. The relative collisional cross sections and the dissociation energy of the NaCs + molecular ion have been obtained from quantitative analysis of the produced atomic and molecular ions. The experimental results are compared with the theoretical values calculated using a model developed by Janev and Mihajlov (1980).

Journal of Physics B Atomic Molecular and Optical Physics•Sep 14, 1991•5 citations

Ionization of Rydberg atoms

Charles E. Burkhardt, Ron Corey, W. P. Garver +3 more

Ion formation in sodium vapor (\ensuremath{\sim}${10}^{11}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$) containing Rydberg atoms (18\ensuremath{\le}n\ensuremath{\le}35) was investigated. Both atomic ions and diatomic molecular ions resulting from collisions between highly excited sodium, ${\mathrm{Na}}^{\mathrm{*}\mathrm{*}}$, and Na(3s) were observed. However, the predominant production mechanism was found to be photoionization of ${\mathrm{Na}}^{\mathrm{*}\mathrm{*}}$ by blackbody radiation, the rate of which was measured at 500 K and found to be \ensuremath{\simeq}5.7\ifmmode\times\else\texttimes\fi{}${10}^{3}$ ${\mathrm{sec}}^{\mathrm{\ensuremath{-}}1}$ for n=18, in good agreement with theory. The ${\mathrm{Na}}^{+}$ signal from blackbody photoionization is observed to be independent of n, which we interpret as implying rapid and nearly complete self-l-mixing, mixing by collisions with Na(3s) atoms, for both s and d states. It is probable, however, that the s states are mixed to the adjacent, n-1, manifold of l states. It was also found that the heavy-body collision cross sections for ${\mathrm{Na}}^{+}$ and ${\mathrm{Na}}_{2}$${\mathrm{}}^{+}$ formation, while roughly three orders of magnitude lower than our estimate of the self-l-mixing cross section, are appreciable, of order 100 A${\r{}}^{2}$.

Physical Review A•Jul 1, 1986•28 citations

Associative ionization in collisions between excited Na atoms in the and the states

Jan Jette Blange, G Aben, H. Rudolph +2 more

For the first time, associative ionization has been observed in an atomic beam of excited sodium atoms in both the and the state. Relative values for the partial cross sections were obtained specified according to the different magnetic substate combinations of the two fine-structure states. These were found to be comparable to those for associative ionization between two atoms. However, the effect of the excitation on the ion production rate was found to be considerable and to depend strongly on the relative polarizations of the laser beams producing the two populations due to the redistribution of the involved magnetic sublevels. The results indicate that the initial orientation of the electron spin S does not significantly influence the associative ionization reaction at the mean collision energy of 25 meV.

Journal of Physics B Atomic Molecular and Optical Physics•Jun 28, 1997•2 citations

Efficient collisional dissociation of Na{sub 2}{sup +} by laser-excited Na (3p)

Charles Tapalian, W. W. Smith

In studying ionization reactions in a single dense effusive beam of laser-excited Na(3p) atoms, we observe production of both Na{sub 2}{sup +} and Na{sup +} ions. The Na{sup +} results from the familiar associative ionization reaction of two Na(3p) atoms and the Na{sup +} ions under our conditions result mostly from the collisional dissociation of the Na{sub 2}{sup +} by reaction with a third excited Na(3p) atom, rather than from photo- dissociation or photoionization. A CW, single-frequency dye laser tuned to 589 nm resonantly excites the Na(3s) atoms to the 3p state. The atomic beam Na(3s) density is determined from low-intensity 589 absorption measurements. Na{sup +} ion yield depends on the cube of the Na beam density, suggesting successive collisions of three Na(3p) atoms: we believe the Na{sub 2}{sup +} ions polarize the third Na(3p) atom, resulting in a R{sup -4} orbiting collision interaction. A large collisional dissociation cross-section of approximately (4{plus_minus}2)x10{sup -13} cm{sup 2} results, for oven temperatures in the 500-600K range.

Bulletin of the American Physical Society•May 1, 1993•0 citations
The results of an experiment on the associative ionization collision between sodium and cesium excited atoms are reported. The atoms are excited by two resonant cw lasers to the 3P3/2{\mathit{P}}_{3/2}P3/2​ and 6P3/2{\mathit{P}}_{3/2}P3/2​ levels, respectively, and the formation of the NaCs+{\mathrm{NaCs}}^{+}NaCs+ molecular ion is observed. The rate constant of such process has been measured relative to the known rate constant of sodium associative ionization and its value resulted in K=(5.4\ifmmode\pm\else\textpm\fi{}3.2)\ifmmode\times\else\texttimes\fi{}10\ensuremath−11{10}^{\mathrm{\ensuremath{-}}11}10\ensuremath−11 cm3{\mathrm{cm}}^{3}cm3 s\ensuremath−1{\mathrm{s}}^{\mathrm{\ensuremath{-}}1}s\ensuremath−1.
Collisional and thermal ionization of sodium n S and n D Rydberg atoms with n = 8–20 has been studied. The experiments were performed using a two-step pulsed laser excitation in an effusive atomic beam at atom density of about 2 × 10 10 cm −3 . Molecular and atomic ions from associative, Penning and thermal ionization processes were detected. It was found that the atomic ions were created mainly due to photoionization of Rydberg atoms by photons of blackbody radiation at the ambient temperature of 300 K. Blackbody ionization rates and effective lifetimes of Rydberg states of interest were determined. The molecular ions were found to be from associative ionization in Na( nL ) + Na(3S) collisions. Rate constants of associative ionization have been measured using an original method based on relative measurements of Na + 2 and Na + ion signals.
We report here measurements of two-body photoassociative ionization collisions between sodium atoms within an ultranarrow velocity class selected from a well-collimated, thermal atomic beam. Doppler-shifted excitation of the Na(3s2{\mathrm{}}^{2}2S1/2{\mathit{S}}_{1/2}S1/2​;F=1)\ensuremath{\rightarrow}Na(5p2{\mathrm{}}^{2}2P3/2{\mathit{P}}_{3/2}P3/2​) transition at 285 nm by a single-mode laser defines the narrow velocity class that subsequently populates the F=2 hyperfine level of the Na ground state by optical pumping. Probe laser beam excitation tuned near the Na(3s2{\mathrm{}}^{2}2S1/2{\mathit{S}}_{1/2}S1/2​;F=2)\ensuremath{\rightarrow}Na(3p2{\mathrm{}}^{2}2P3/2{\mathit{P}}_{3/2}P3/2​;F=3) transition produced photoassociative ionization with an average collision energy EK{\mathit{E}}_{\mathit{K}}EK​ corresponding to a temperature of 5.3 mK (EK{\mathit{E}}_{\mathit{K}}EK​=3/2kT). We determine the rate constant for the process as a function of probe beam intensity and polarization.
An investigation of the 'Hornbeck-Molnar ionization' process between laser-excited Cs and ground state Na atoms has been performed in a crossed beam apparatus. Caesium atoms in the 8d, 10s, 9d, 11s and 10d levels respectively have been obtained by two-step resonant CW laser excitation. The relative collisional cross sections and the dissociation energy of the NaCs + molecular ion have been obtained from quantitative analysis of the produced atomic and molecular ions. The experimental results are compared with the theoretical values calculated using a model developed by Janev and Mihajlov (1980).
Ion formation in sodium vapor (\ensuremath{\sim}1011{10}^{11}1011 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$) containing Rydberg atoms (18\ensuremath{\le}n\ensuremath{\le}35) was investigated. Both atomic ions and diatomic molecular ions resulting from collisions between highly excited sodium, Na∗∗{\mathrm{Na}}^{\mathrm{*}\mathrm{*}}Na∗∗, and Na(3s) were observed. However, the predominant production mechanism was found to be photoionization of Na∗∗{\mathrm{Na}}^{\mathrm{*}\mathrm{*}}Na∗∗ by blackbody radiation, the rate of which was measured at 500 K and found to be \ensuremath{\simeq}5.7\ifmmode\times\else\texttimes\fi{}103{10}^{3}103 ${\mathrm{sec}}^{\mathrm{\ensuremath{-}}1}$ for n=18, in good agreement with theory. The Na+{\mathrm{Na}}^{+}Na+ signal from blackbody photoionization is observed to be independent of n, which we interpret as implying rapid and nearly complete self-l-mixing, mixing by collisions with Na(3s) atoms, for both s and d states. It is probable, however, that the s states are mixed to the adjacent, n-1, manifold of l states. It was also found that the heavy-body collision cross sections for Na+{\mathrm{Na}}^{+}Na+ and Na2{\mathrm{Na}}_{2}Na2​+{\mathrm{}}^{+}+ formation, while roughly three orders of magnitude lower than our estimate of the self-l-mixing cross section, are appreciable, of order 100 A˚2{\r{}}^{2}˚2.
For the first time, associative ionization has been observed in an atomic beam of excited sodium atoms in both the and the state. Relative values for the partial cross sections were obtained specified according to the different magnetic substate combinations of the two fine-structure states. These were found to be comparable to those for associative ionization between two atoms. However, the effect of the excitation on the ion production rate was found to be considerable and to depend strongly on the relative polarizations of the laser beams producing the two populations due to the redistribution of the involved magnetic sublevels. The results indicate that the initial orientation of the electron spin S does not significantly influence the associative ionization reaction at the mean collision energy of 25 meV.
In studying ionization reactions in a single dense effusive beam of laser-excited Na(3p) atoms, we observe production of both Na{sub 2}{sup +} and Na{sup +} ions. The Na{sup +} results from the familiar associative ionization reaction of two Na(3p) atoms and the Na{sup +} ions under our conditions result mostly from the collisional dissociation of the Na{sub 2}{sup +} by reaction with a third excited Na(3p) atom, rather than from photo- dissociation or photoionization. A CW, single-frequency dye laser tuned to 589 nm resonantly excites the Na(3s) atoms to the 3p state. The atomic beam Na(3s) density is determined from low-intensity 589 absorption measurements. Na{sup +} ion yield depends on the cube of the Na beam density, suggesting successive collisions of three Na(3p) atoms: we believe the Na{sub 2}{sup +} ions polarize the third Na(3p) atom, resulting in a R{sup -4} orbiting collision interaction. A large collisional dissociation cross-section of approximately (4{plus_minus}2)x10{sup -13} cm{sup 2} results, for oven temperatures in the 500-600K range.