Solar system ices

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Table of contents

Introduction 
I Context(s) 
I.1 Astrophysical context
I.1.1 Molecules in the universe
I.1.1.1 The interstellar medium
I.1.1.2 Dust and ice mantles
I.1.1.3 Solar system ices
I.1.1.4 Sources of irradiations
I.1.2 Role of non-thermal desorption
I.1.2.1 Different non-thermal desorption processes
I.1.2.2 Astrochemical models
I.1.2.3 Observations
I.2 Vacuum technology context
I.2.1 Non-thermal desorption in vacuum dynamics
I.2.2 Non-thermal desorption in the context of accelerators and the LHC
I.2.2.1 Brief description of the LHC
I.2.2.2 The different sources of non-thermal desorption in accelerators
II Fundamental mechanisms of photon and electron-induced desorption
II.1 Position of the problem
II.2 Interaction of photons and electrons with molecular ices
II.2.1 Ices/molecular solids
II.2.2 Electronic transitions
II.2.3 From free molecules to molecular solids
II.2.4 Electron-matter interaction
II.2.4.1 Stopping power
II.2.4.2 Compounds
II.2.4.3 Penetration and energy deposition profiles
II.2.4.4 Low-energy (< 20 eV) electrons
II.2.5 X-ray photons: core excitations and Auger decay
II.2.5.1 EXAFS, Shape resonances
II.3 Historic models of photon- and electron-induced desorption
II.3.1 The MGR model
II.3.2 Non-MGR models
II.4 A case study: desorption mechanisms from rare-gas solids
II.4.1 Electronic excitations in RGS: excitons
II.4.2 Desorption mechanisms
II.5 Desorption from molecular ices
III Experimental methods
III.1 Techniques
III.1.1 Ultra-high vacuum
III.1.2 Mass spectrometry
III.1.2.1 Mass filtering
III.1.2.2 Ionization source
III.1.2.3 Detection
III.1.2.4 Residual gas analysis
III.1.2.5 Kinetic energy analysis with an electrostatic deflector
III.1.3 Ice growth
III.1.4 Temperature-programmed desorption
III.1.5 Infrared spectroscopy
III.1.6 Electron yield
III.1.7 Calibration of EID and PID
III.1.7.1 Absolute calibration methods
III.1.7.2 Relative calibration methods
III.1.7.3 Fragments and reflected light
III.2 Electron-induced desorption studies at CERN
III.2.1 The Multisystem set-up
III.2.2 Measurement procedure
III.3 SPICES II at LERMA
III.4 Synchrotron-based experiments
III.4.1 Synchrotron light and its advantages
III.4.2 Experiments on the DESIRS beamline
III.4.3 Experiments on the SEXTANTS beamline
III.5 Development of a UV laser desorption and spectroscopy set-up in the lab
III.5.1 UV and VUV laser desorption
III.5.1.1 VUV generation
III.5.1.2 Practical implementation
III.5.2 REMPI spectroscopy
III.5.3 Desorption + REMPI set-up
IV VUV photon-induced desorption
IV.1 Pure ice systems
IV.1.1 CO
IV.1.1.1 Recent studies on CO photodesorption
IV.1.1.2 Thickness and deposition temperature dependence of CO photodesorption
IV.1.1.3 Photodesorption mechanisms
IV.1.2 NO
IV.1.2.1 Synchrotron wavelength-resolved study
IV.1.2.2 NO gas phase REMPI
IV.1.2.3 NO desorption + REMPI
IV.1.3 CH4
IV.1.4 H2O
IV.1.4.1 Water ice structure and electronic spectrum
IV.1.4.2 Photodesorption yields and mechanisms in the literature
IV.1.4.3 Experimental results from synchrotron study
IV.1.5 NH3
IV.1.5.1 Photodesorption spectra and yields
IV.1.6 Other organic molecules
IV.1.6.1 Photodesorption from HCOOH ice
IV.1.6.2 Photodesorption from organic molecules
IV.1.7 Perspectives and limits for pure ices
IV.2 Indirect desorption: model layered ices
IV.2.1 CO-induced indirect desorption
IV.2.1.1 Single layers
IV.2.1.2 Multiple layers and other systems
IV.2.1.3 Discussion
IV.2.2 H2O-induced desorption
IV.2.2.1 Results on single and multilayers on H2O and D2O
IV.2.2.2 Discussion
IV.2.3 Other systems
IV.3 Implementation in astrochemical models spectral dependence
IV.4 Conclusions
V Electron-induced desorption
V.1 Chemically inactive pure ices: N2 and Ar
V.1.1 Interpretation of EID yield curves
V.1.2 N2
V.1.3 Ar
V.1.4 Ar mixed with impurities: effects of ice composition
V.2 CO, CO2, H2O and the role of chemistry
V.2.1 CO
V.2.2 CO2
V.2.3 H2O
V.3 Relevance of the data to astrophysical and accelerator contexts
V.4 Conclusions and perspectives on electron-induced desorption
VI X-ray photon-induced desorption
VI.1 H2O X-ray photodesorption
VI.1.1 Ice absorption spectroscopy and structure
VI.1.2 Desorption of neutral species, and astrophysical relevance of X-ray photodesorption
VI.1.3 Desorption of ions
VI.1.3.1 H− desorption
VI.1.3.2 Oxygen fragments desorption
VI.1.3.3 H+ desorption
VI.2 CO X-ray photodesorption
VI.2.1 Effects of the irradiation: TEY evolution
VI.2.2 Desorption of neutral species
VI.2.3 Desorption of ions
VI.2.3.1 Ice charging and ageing
VI.2.3.2 Mass spectrum of cations
VI.2.3.3 Spectral signatures
VI.2.4 Discussion on X-ray induced photochemistry
VI.2.4.1 CO irradiation chemistry
VI.2.4.2 Comparison of different probes of chemistry
VI.2.5 Astrophysical yields
VI.3 Conclusions on X-ray photodesorption
Conclusion 
Appendix A: Calibration values
Bibliographie