A series of experiments have been performed in which zinc atoms carried in a flowing stream of helium are excited to the 4(3P1) state by optical pumping with a XeCl excimer laser. Addition of calcium atoms to the flow results in quenching of the excited zinc atoms. The cross section for this energy transfer process is σ?3×10−16 cm2, corresponding to Zn(4 3PJ) quenching in fewer than 10 collisons with calcium atoms. Subsequent to optical excitation of the zinc atoms, emission was observed from both the 4 1P1 and 5 3S1 excited states of calcium. Integration of the intensities of the calcium emissions indicated that excitation of the singlet and triplet manifolds in calcium occurs with comparable probability, suggesting that spin conservation is not a strong constraint in the energy transfer process. Summation of the intensities indicate that the E–E transfer process accounts for most of the quenching of the excited zinc atoms.A series of experiments have been performed in which zinc atoms carried in a flowing stream of helium are excited to the 4(3P1) state by optical pumping with a XeCl excimer laser. Addition of calcium atoms to the flow results in quenching of the excited zinc atoms. The cross section for this energy transfer process is σ?3×10−16 cm2, corresponding to Zn(4 3PJ) quenching in fewer than 10 collisons with calcium atoms. Subsequent to optical excitation of the zinc atoms, emission was observed from both the 4 1P1 and 5 3S1 excited states of calcium. Integration of the intensities of the calcium emissions indicated that excitation of the singlet and triplet manifolds in calcium occurs with comparable probability, suggesting that spin conservation is not a strong constraint in the energy transfer process. Summation of the intensities indicate that the E–E transfer process accounts for most of the quenching of the excited zinc atoms.

The Journal of Chemical PhysicsJan 15, 19815 citations

EXCITATION TRANSFER IN HELIUM.

I. P. Bogdanova, V. D. Marusin

Jan 1, 19720 citations

Excitation-Transfer Collisions between Rubidium and Helium Atoms

T. J. Beahn, W. J. Condell, Hirsch I. Mandelberg

An experiment is described which measures the collision cross section for transfer of excitation in rubidium by helium. Rubidium atoms are pumped to either the $^{2}P_{\frac{1}{2}}$ or $^{2}P_{\frac{3}{2}}$ state by irradiation with one of the resonance lines. Some excited rubidium atoms are transferred to the other $P$ state by collisions with helium atoms. The rubidium atoms then radiate both resonance lines. Measurements of the intensities of both resonance lines as a function of helium pressure are used to calculate the collision cross section. The cross section for $^{2}P_{\frac{1}{2}}$ to $^{2}P_{\frac{3}{2}}$ is 1.0\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$ ${\mathrm{cm}}^{2}$ \ifmmode\pm\else\textpm\fi{}10% and for $^{2}P_{\frac{3}{2}}$ to $^{2}P_{\frac{1}{2}}$ is 1.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$ ${\mathrm{cm}}^{2}$ \ifmmode\pm\else\textpm\fi{}10%.An experiment is described which measures the collision cross section for transfer of excitation in rubidium by helium. Rubidium atoms are pumped to either the $^{2}P_{\frac{1}{2}}$ or $^{2}P_{\frac{3}{2}}$ state by irradiation with one of the resonance lines. Some excited rubidium atoms are transferred to the other $P$ state by collisions with helium atoms. The rubidium atoms then radiate both resonance lines. Measurements of the intensities of both resonance lines as a function of helium pressure are used to calculate the collision cross section. The cross section for $^{2}P_{\frac{1}{2}}$ to $^{2}P_{\frac{3}{2}}$ is 1.0\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$ ${\mathrm{cm}}^{2}$\ifmmode\pm\else\textpm\fi{}10% and for $^{2}P_{\frac{3}{2}}$ to $^{2}P_{\frac{1}{2}}$ is 1.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$ ${\mathrm{cm}}^{2}$\ifmmode\pm\else\textpm\fi{}10%.

Physical ReviewJan 7, 196628 citations

Distribution of Excitation Transfer in Helium

John D. Jobe, Robert M. St. John

Physical Review AMay 1, 19720 citations

An experiment is described which measures the collision cross section for transfer of excitation in rubidium by helium. Rubidium atoms are pumped to either the

^{2}P_{\frac{1}{2}}

^{2}P_{\frac{3}{2}}

state by irradiation with one of the resonance lines. Some excited rubidium atoms are transferred to the other

P

state by collisions with helium atoms. The rubidium atoms then radiate both resonance lines. Measurements of the intensities of both resonance lines as a function of helium pressure are used to calculate the collision cross section. The cross section for

^{2}P_{\frac{1}{2}}

^{2}P_{\frac{3}{2}}

is 1.0\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$

{\mathrm{cm}}^{2}

\ifmmode\pm\else\textpm\fi{}10% and for

^{2}P_{\frac{3}{2}}

^{2}P_{\frac{1}{2}}

is 1.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}17}$

{\mathrm{cm}}^{2}

\ifmmode\pm\else\textpm\fi{}10%.