We have measured cold titanium-helium collisions that cause transitions between the fine-structure levels of the $[3{d}^{2}4{s}^{2}]\phantom{\rule{0.3em}{0ex}}^{3}F_{J}$ electronic ground state of atomic titanium, over a temperature range from 5 to $20\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ . The $\mathrm{Ti}\text{\ensuremath{-}}\mathrm{He}$ inelastic collision cross section is significantly smaller than cross sections measured for collisions of non-transition-metal atoms with noble gas atoms. Our theoretical calculations of the inelastic cross sections reproduce the magnitude and temperature dependence of the measurements, and attribute the suppression of inelastic collisions to titanium's ``submerged'' $d$ -shell valence electrons.We have measured cold titanium-helium collisions that cause transitions between the fine-structure levels of the $[3{d}^{2}4{s}^{2}]\phantom{\rule{0.3em}{0ex}}^{3}F_{J}$ electronic ground state of atomic titanium, over a temperature range from 5 to $20\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. The $\mathrm{Ti}\text{\ensuremath{-}}\mathrm{He}$ inelastic collision cross section is significantly smaller than cross sections measured for collisions of non-transition-metal atoms with noble gas atoms. Our theoretical calculations of the inelastic cross sections reproduce the magnitude and temperature dependence of the measurements, and attribute the suppression of inelastic collisions to titanium's ``submerged'' $d$-shell valence electrons.

Physical Review AJun 10, 200830 citations

Collisional processes in exotic atoms

Grigory Ya. Korenman

Springer eBooksJan 1, 20120 citations

Inelastic titanium-titanium collisions

Mei-Ju Lu, Vijay Singh, Jonathan D. Weinstein

We have measured cold inelastic collisions between neutral ground-state titanium atoms: collisions that cause transitions between the different magnetic sublevels of the $[3{d}^{2}4{s}^{2}]{^{3}F}_{2}$ ground state of $^{50}\text{T}\text{i}$ , as well as collisions that cause transitions between the fine-structure levels of the $[3{d}^{2}4{s}^{2}]{^{3}F}_{J}$ electronic ground state. Both processes occur with large rate coefficients, as would be expected from titanium's anisotropic electronic potential.We have measured cold inelastic collisions between neutral ground-state titanium atoms: collisions that cause transitions between the different magnetic sublevels of the $[3{d}^{2}4{s}^{2}]{^{3}F}_{2}$ ground state of $^{50}\text{T}\text{i}$, as well as collisions that cause transitions between the fine-structure levels of the $[3{d}^{2}4{s}^{2}]{^{3}F}_{J}$ electronic ground state. Both processes occur with large rate coefficients, as would be expected from titanium's anisotropic electronic potential.

Physical Review AMay 26, 200916 citations

Collisional processes in exotic atoms

Grigory Ya. Korenman

Hyperfine InteractionsJan 31, 20121 citation

INELASTIC COLLISIONS OF SLOW ATOMS

Борис М. Смирнов

Oct 1, 19640 citations

Measurement of fine-structure changing collision in ultracold /sup 85/Rb held in a MOT

Luís Gustavo Marcassa, R. Zanon, Vanderlei Salvador Bagnato +3 more

Summary form only given. In a magneto-optical trap (MOT) two main mechanisms contribute to the total trap loss rate. Radiative escape (RE), where the spontaneous emission within the collision duration transforms internal energy into kinetic motion. Fine-structure changing collision (FSC) is an exoergic process where a pair of excited ground state atoms undergoes a change to the lower state of the fine-structure doublet, followed by a release of /spl Delta/E/sub FSC//2 in kinetic energy normally enough to eject the atoms from the trap. In earlier experiments only the total trap loss rate, which is the sum of contributions from RE and FSC, was determined. Distinguishing between these two mechanisms is important because it allows a more precise comparison with the theory, leading to a better understanding of exoergic cold collisions. In this experiment the FSC contribution to the total loss in /sup 85/Rb is measured by direct photoionization of the P/sub 1/2/ fragments.Summary form only given. In a magneto-optical trap (MOT) two main mechanisms contribute to the total trap loss rate. Radiative escape (RE), where the spontaneous emission within the collision duration transforms internal energy into kinetic motion. Fine-structure changing collision (FSC) is an exoergic process where a pair of excited ground state atoms undergoes a change to the lower state of the fine-structure doublet, followed by a release of /spl Delta/E/sub FSC//2 in kinetic energy normally enough to eject the atoms from the trap. In earlier experiments only the total trap loss rate, which is the sum of contributions from RE and FSC, was determined. Distinguishing between these two mechanisms is important because it allows a more precise comparison with the theory, leading to a better understanding of exoergic cold collisions. In this experiment the FSC contribution to the total loss in /sup 85/Rb is measured by direct photoionization of the P/sub 1/2/ fragments.

Quantum Electronics and Laser Science ConferenceJan 20, 20030 citations

We have measured cold titanium-helium collisions that cause transitions between the fine-structure levels of the

[3{d}^{2}4{s}^{2}]\phantom{\rule{0.3em}{0ex}}^{3}F_{J}

electronic ground state of atomic titanium, over a temperature range from 5 to

20\phantom{\rule{0.3em}{0ex}}\mathrm{K}

. The $\mathrm{Ti}\text{\ensuremath{-}}\mathrm{He}$ inelastic collision cross section is significantly smaller than cross sections measured for collisions of non-transition-metal atoms with noble gas atoms. Our theoretical calculations of the inelastic cross sections reproduce the magnitude and temperature dependence of the measurements, and attribute the suppression of inelastic collisions to titanium's ``submerged''

d

-shell valence electrons.

We have measured cold inelastic collisions between neutral ground-state titanium atoms: collisions that cause transitions between the different magnetic sublevels of the

[3{d}^{2}4{s}^{2}]{^{3}F}_{2}

ground state of

^{50}\text{T}\text{i}

, as well as collisions that cause transitions between the fine-structure levels of the

[3{d}^{2}4{s}^{2}]{^{3}F}_{J}

electronic ground state. Both processes occur with large rate coefficients, as would be expected from titanium's anisotropic electronic potential.