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dc.contributor.advisorOrlando, Thomas
dc.contributor.authorDeSimone, Alice Johnson
dc.date.accessioned2014-01-13T16:48:15Z
dc.date.available2014-01-13T16:48:15Z
dc.date.created2013-12
dc.date.issued2013-11-06
dc.date.submittedDecember 2013
dc.identifier.urihttp://hdl.handle.net/1853/50322
dc.description.abstractThe temperature-programmed desorption profiles of water from three lunar analogs were measured. These experiments showed that glassy materials were hydrophobic, that water on multiphase materials occupied a continuum of adsorption sites, and that feldspar exhibited significant chemisorption of water. The competition between photodissociation and photodesorption of amorphous solid water (ASW) was investigated on three substrates: copper with a thin oxide coating, an impact melt breccia from Apollo 16, and a mare basalt from Apollo 17. The rotational temperature of desorbing H₂O did not vary significantly with substrate, but the H₂O time-of-flight spectra were broader on the lunar slabs than on copper. Additionally, the cross sections for water removal at low coverages were higher on the lunar slabs than on copper. O(³PJ) produced by 157-nm irradiation of ASW on the same three substrates was measured as a function of spin-orbit state, H₂O exposure, and irradiation time. The same Maxwell-Boltzmann components were present in each case, with translational temperatures of 10,000 K, 1800 K, 400 K, and the surface temperature, but the relative intensities of these components differed widely between substrates. Evidence for diffusion out of pores in the ASW and in the lunar slabs was observed for H2O exposures of at least 1 Langmuir. Cross sections for H2O and O(3PJ) depletion due to 157-nm irradiation of ASW were applied to icy grains in the rings of Saturn, and corresponding cross sections on the lunar substrates were used to estimate the flux of water desorbing from the Moon and the density of oxygen atoms in the lunar atmosphere.
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherGeorgia Institute of Technology
dc.subjectAmorphous solid water
dc.subjectMoon
dc.subjectCross section
dc.subjectDesorption
dc.subjectAtomic oxygen
dc.subject.lcshWater
dc.subject.lcshOuter space
dc.subject.lcshUltraviolet radiation
dc.subject.lcshPhotons
dc.subject.lcshCryochemistry
dc.titleThermal desorption, photodesorption, and photodissociation of water on amorphous ice and lunar surfaces
dc.typeDissertation
dc.description.degreePh.D.
dc.contributor.departmentChemistry and Biochemistry
thesis.degree.levelDoctoral
dc.contributor.committeeMemberBrown, Ken
dc.contributor.committeeMemberHuey, Greg
dc.contributor.committeeMemberJanata, Jiri
dc.contributor.committeeMemberWine, Paul H.
dc.date.updated2014-01-13T16:48:15Z


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