dc.contributor.advisor | Doyle, John M. | |
dc.contributor.author | Au, Yat Shan | |
dc.date.accessioned | 2014-06-06T17:33:53Z | |
dc.date.issued | 2014-06-06 | |
dc.date.submitted | 2014 | |
dc.identifier.citation | Au, Yat Shan. 2014. Inelastic collisions of atomic thorium and molecular thorium monoxide with cold helium-3. Doctoral dissertation, Harvard University. | en_US |
dc.identifier.other | http://dissertations.umi.com/gsas.harvard:11318 | en |
dc.identifier.uri | http://nrs.harvard.edu/urn-3:HUL.InstRepos:12274226 | |
dc.description.abstract | We measure inelastic cross sections for atomic thorium (Th) and molecular thorium monoxide (ThO) in collisions with $^3$He at temperatures near 1 K. We determine the Zeeman relaxation cross section for Th ($^3$F$_2$) to be $\sim 2 \times 10^{-17}$~cm$^{-2}$ at 800~mK. We study electronic inelastic processes in Th ($^3$P$_0$) and find no quenching even after $10^6$ collisions at 800~mK. We measure the vibrational quenching cross section for ThO~(X,~$\nu=1$) to be $(7.9 \pm 2.7) \times 10^{-19}$~cm$^{-2}$ at 800~mK. Finally, we observe indirect evidence for ThO (X, $\nu=0$)--$^3$He van der Waals complex formation, and measure the 3-body recombination rate constant to be $\Gamma_3 = (8 \pm 2) \times 10^{-33}$~cm$^6$s$^{-1}$ at 2.4~K. The stability of the ground Th ($^3$F$_2$) state, metastable Th ($^3$P$_0$) state, and vibrational excited ThO (X, $\nu=1$) state provides data on anisotropic interactions in new systems and opens up the possibility for further studies and experiments, including trapping. | en_US |
dc.description.sponsorship | Physics | en_US |
dc.language.iso | en_US | en_US |
dash.license | LAA | |
dc.subject | Physics | en_US |
dc.subject | buffer gas cooling | en_US |
dc.subject | thorium | en_US |
dc.subject | thorium monoxide | en_US |
dc.title | Inelastic collisions of atomic thorium and molecular thorium monoxide with cold helium-3 | en_US |
dc.type | Thesis or Dissertation | en_US |
dash.depositing.author | Au, Yat Shan | |
dc.date.available | 2014-06-06T17:33:53Z | |
thesis.degree.date | 2014 | en_US |
thesis.degree.discipline | Physics | en_US |
thesis.degree.grantor | Harvard University | en_US |
thesis.degree.level | doctoral | en_US |
thesis.degree.name | Ph.D. | en_US |
dc.contributor.committeeMember | Gabrielse, Gerald | en_US |
dc.contributor.committeeMember | Jafferis, Daniel | en_US |
dash.contributor.affiliated | Au, Yat Shan | |