title: Dynamics of anions and ultracold atoms in a hybrid atom-ion trap. creator: Hassan, Saba Zia subject: ddc-530 subject: 530 Physics description: In this work, the dynamics of anion-neutral interactions are studied in a hybrid atom-ion trap. An octupole radio-frequency trap is used for trapping anions, and a dark spontaneous-force optical trap is employed to create ultracold rubidium (Rb) atoms. Spatial density distributions of the ion and atom clouds are determined via photodetachment tomography and saturation absorption imaging, respectively. A method to map the ions’ translational temperature onto their time of flight to the detector is presented. This technique is applied to determine the temperature of OH−anions as they undergo laser-induced forced evaporative cooling to temperatures below 4 K. The dynamics of associative electronic detachment reaction between closed-shell anions OH−and alkali atoms are investigated where for a ground-state Rb the influence of a dipole-bound state as a reaction intermediate is observed. The interaction dynamics of Rb with OH−(H2O) are also explored, where a smaller atom-to-ion mass ratio favors sympathetic cooling via elastic collisions. For atomic O−, the detachment processes involving ground-state Rb are found to be closed and efficient anion sympathetic cooling, via ultracold Rb, is observed. These results present hybrid systems as a platform to investigate anion-neutral collision dynamics, particularly interesting for astrochemistry, fundamental physics, and quantum chemistry. date: 2022 type: Dissertation type: info:eu-repo/semantics/doctoralThesis type: NonPeerReviewed format: application/pdf identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/31692/1/2022_Dissertation_Saba_Hassan_HGSFP.pdf identifier: DOI:10.11588/heidok.00031692 identifier: urn:nbn:de:bsz:16-heidok-316927 identifier: Hassan, Saba Zia (2022) Dynamics of anions and ultracold atoms in a hybrid atom-ion trap. [Dissertation] relation: https://archiv.ub.uni-heidelberg.de/volltextserver/31692/ rights: info:eu-repo/semantics/openAccess rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html language: eng