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Hacquard AB, Torres-DÍaz D, Basalgète R, Toulouse D, Féraud G, Del Fré S, Noble JA, Philippe L, Michaut X, Fillion JH, Lafosse A, Amiaud L, Bertin M. Flux and fluence effects on the vacuum-UV photodesorption and photoprocessing of CO 2 ices. Phys Chem Chem Phys 2024; 26:18741-18752. [PMID: 38934118 DOI: 10.1039/d4cp01177e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
CO2 is a major component of the icy mantles surrounding dust grains in planet and star formation regions. Understanding its photodesorption is crucial for explaining gas phase abundances in the coldest environments of the interstellar medium irradiated by vacuum-UV (VUV) photons. Photodesorption yields determined experimentally from CO2 samples grown at low temperatures (T = 15 K) have been found to be very sensitive to experimental methods and conditions. Several mechanisms have been suggested for explaining the desorption of CO2, O2 and CO from CO2 ices. In the present study, the cross-sections characterizing the dynamics of photodesorption as a function of photon fluence (determined from released molecules in the gas phase) and of ice composition modification (determined in situ in the solid phase) are compared for the first time for different photon flux conditions (from 7.3 × 1012 photon per s cm-2 to 2.2× 1014 photon per s cm-2) using monochromatic synchrotron radiation in the VUV range (on the DESIRS beamline at SOLEIL). This approach reveals that CO and O2 desorptions are decorrelated from that of CO2. CO and O2 photodesorption yields depend on photon flux conditions and can be linked to surface chemistry. In contrast, the photodesorption yield of CO2 is independent of the photon flux conditions and can be linked to bulk ice chemical modification, consistently with indirect desorption induced by an electronic transition (DIET) process.
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Affiliation(s)
- Antoine B Hacquard
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
- Sorbonne Université, Observatoire de Paris, PSL university, CNRS, LERMA, F-75005, Paris, France
| | - Daniela Torres-DÍaz
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405 Orsay, France
| | - Romain Basalgète
- Sorbonne Université, Observatoire de Paris, PSL university, CNRS, LERMA, F-75005, Paris, France
| | - Delfina Toulouse
- Sorbonne Université, Observatoire de Paris, PSL university, CNRS, LERMA, F-75005, Paris, France
| | - Géraldine Féraud
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
| | - Samuel Del Fré
- Univ. Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers Atomes et Molécules, F-59000 Lille, France
| | - Jennifer A Noble
- Physique des Interactions Ioniques et Moléculaires, CNRS, Aix Marseille Univ., 13397 Marseille, France
| | - Laurent Philippe
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
| | - Xavier Michaut
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
| | | | - Anne Lafosse
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405 Orsay, France
| | - Lionel Amiaud
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405 Orsay, France
| | - Mathieu Bertin
- Sorbonne Université CNRS, MONARIS, UMR8233, F-75005 Paris, France.
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2
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Maillet JB, Da Costa G, Klaes B, Bacchi C, Normand A, Vaudaulon C, Vurpillot F. In Situ Pulsed Hydrogen Implantation in Atom Probe Tomography. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2024:ozae040. [PMID: 38758982 DOI: 10.1093/mam/ozae040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 04/04/2024] [Accepted: 04/23/2024] [Indexed: 05/19/2024]
Abstract
The investigation of hydrogen in atom probe tomography appears as a relevant challenge due to its low mass, high diffusion coefficient, and presence as a residual gas in vacuum chambers, resulting in multiple complications for atom probe studies. Different solutions were proposed in the literature like ex situ charging coupled with cryotransfer or H charging at high temperature in a separate chamber. Nevertheless, these solutions often faced challenges due to the complex control of specimen temperature during hydrogen charging and subsequent analysis. In this paper, we propose an alternative route for in situ H charging in atom probe derived from a method developed in field ion microscopy. By applying negative voltage nanosecond pulse on the specimen in an atom probe chamber under a low pressure of H2, it is demonstrated that a high dose of H can be implanted in the range 2-20 nm beneath the specimen surface. An atom probe chamber was modified to enable direct negative pulse application with controlled gas pressure, pulse repetition rate, and pulse amplitude. Through electrodynamical simulations, we show that the implantation energy falls within the range 100-1,000 eV and a theoretical depth of implantation was predicted and compared to experiments.
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Affiliation(s)
- Jean-Baptiste Maillet
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - Gerald Da Costa
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - Benjamin Klaes
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - Christian Bacchi
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - Antoine Normand
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - Charly Vaudaulon
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
| | - François Vurpillot
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, Av. de l'Université, 76800 Saint-Etienne-du-Rouvray, France
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3
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Szalay JR, Allegrini F, Ebert RW, Bagenal F, Bolton SJ, Fatemi S, McComas DJ, Pontoni A, Saur J, Smith HT, Strobel DF, Vance SD, Vorburger A, Wilson RJ. Oxygen production from dissociation of Europa's water-ice surface. NATURE ASTRONOMY 2024; 8:567-576. [PMID: 38798715 PMCID: PMC11111413 DOI: 10.1038/s41550-024-02206-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 01/17/2024] [Indexed: 05/29/2024]
Abstract
Jupiter's moon Europa has a predominantly water-ice surface that is modified by exposure to its space environment. Charged particles break molecular bonds in surface ice, thus dissociating the water to ultimately produce H2 and O2, which provides a potential oxygenation mechanism for Europa's subsurface ocean. These species are understood to form Europa's primary atmospheric constituents. Although remote observations provide important global constraints on Europa's atmosphere, the molecular O2 abundance has been inferred from atomic O emissions. Europa's atmospheric composition had never been directly sampled and model-derived oxygen production estimates ranged over several orders of magnitude. Here, we report direct observations of H2+ and O2+ pickup ions from the dissociation of Europa's water-ice surface and confirm these species are primary atmospheric constituents. In contrast to expectations, we find the H2 neutral atmosphere is dominated by a non-thermal, escaping population. We find 12 ± 6 kg s-1 (2.2 ± 1.2 × 1026 s-1) O2 are produced within Europa's surface, less than previously thought, with a narrower range to support habitability in Europa's ocean. This process is found to be Europa's dominant exogenic surface erosion mechanism over meteoroid bombardment.
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Affiliation(s)
- J. R. Szalay
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ USA
| | - F. Allegrini
- Southwest Research Institute, San Antonio, TX USA
- Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX USA
| | - R. W. Ebert
- Southwest Research Institute, San Antonio, TX USA
- Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX USA
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO USA
| | - S. J. Bolton
- Southwest Research Institute, San Antonio, TX USA
| | - S. Fatemi
- Department of Physics, University of Umeå, Umeå, Sweden
| | - D. J. McComas
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ USA
| | - A. Pontoni
- Southwest Research Institute, San Antonio, TX USA
| | - J. Saur
- Institute of Geophysics and Meteorology, University of Cologne, Cologne, Germany
| | - H. T. Smith
- The Johns Hopkins University Applied Physics Laboratory, Baltimore, MD USA
| | | | - S. D. Vance
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - A. Vorburger
- Physics Institute, University of Bern, Bern, Switzerland
| | - R. J. Wilson
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO USA
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4
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Weiser A, Lanz A, Hunter ED, Simon MC, Widmann E, Murtagh DJ. A compact low energy proton source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:103301. [PMID: 37782215 DOI: 10.1063/5.0162339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 09/12/2023] [Indexed: 10/03/2023]
Abstract
A low energy proton source for non-neutral plasma experiments was developed. Electrons from a hot filament ionize H2 gas inside a geometrically compensated Penning trap to produce protons via dissociative ionization. A rotating wall electric field destabilizes the unwanted H2+ and H3+ generated in the process while concentrating protons at the center of the trap. The source produces bunches of protons with relatively low ion contamination (5.5% H2+ and 15.5% H3+), with energy tunable from 35 to 300 eV.
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Affiliation(s)
- A Weiser
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
- Vienna Doctoral School in Physics, University of Vienna, Vienna, Austria
| | - A Lanz
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
- Vienna Doctoral School in Physics, University of Vienna, Vienna, Austria
| | - E D Hunter
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
| | - M C Simon
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
| | - E Widmann
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
| | - D J Murtagh
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Sciences, Kegelgasse 27, 1030 Wien, Austria
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5
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Bertin M, Basalgète R, Ocaña AJ, Féraud G, Romanzin C, Philippe L, Michaut X, Fillion JH. Vacuum UV photodesorption of organics in the interstellar medium: an experimental study of formic acid HCOOH and methyl formate HCOOCH 3-containing ices. Faraday Discuss 2023; 245:488-507. [PMID: 37309601 DOI: 10.1039/d3fd00004d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Being a potential process that could explain gas phase abundances of so-called complex organic molecules (COMs) in the cold interstellar medium (ISM), the UV photon-induced desorption from organics-containing molecular ices has been experimentally studied. In this work, we focused on the observation of the photodesorbed products and the measurement of the associated photodesorption yields from pure and mixed molecular ices, each containing organic molecules whose detection has been achieved in the gas phase of the cold ISM, namely formic acid HCOOH and methyl formate HCOOCH3. Each molecule, in pure ice or in ice mixed with CO or water, was irradiated at 15 K with monochromatic vacuum UV photons in the 7-14 eV range using synchrotron radiation from the SOLEIL synchrotron facility, DESIRS beamline. Photodesorption yields of the intact molecules and of the photoproducts were derived as a function of the incident photon energy. Experiments have revealed that the desorbing species match the photodissociation pattern of each isolated molecule, with little influence of the kind of ice (pure or mixed in CO or H2O-rich environment). For both species, the photodesorption of the intact organics is found to be negligible in our experimental conditions, resulting in yields typically below 10-5 ejected molecules per incident photon. The results obtained on HCOOH and HCOOCH3-containing ices are similar to what has already been found for methanol-containing ices, but contrast with the case of another complex molecule, CH3CN, photodesorption of which has been recently studied. Such experimental results may be linked to the observation of COMs in protoplanetary disks, in which CH3CN is commonly observed whereas HCOOH or methanol are detected only in some sources, HCOOCH3 not being detected at all.
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Affiliation(s)
- Mathieu Bertin
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Romain Basalgète
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Antonio J Ocaña
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Géraldine Féraud
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Claire Romanzin
- Univ. Paris-Saclay, CNRS UMR 8000, ICP, F-91405, Orsay, France
| | - Laurent Philippe
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Xavier Michaut
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
| | - Jean-Hugues Fillion
- Sorbonne Université, Observatoire de Paris, PSL University, CNRS, LERMA, F-75005, Paris, France.
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6
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Kumar A, Swain S, Prabhudesai VS. Inelastic electron scattering induced quantum coherence in molecular dynamics. Nat Commun 2023; 14:2769. [PMID: 37179339 PMCID: PMC10183011 DOI: 10.1038/s41467-023-38440-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
Quantum coherence is pivotal in various applications ranging from chemical control to quantum computing. An example of its manifestation in molecular dynamics is inversion symmetry breaking in the photodissociation of homonuclear diatomic molecules. On the other hand, the dissociative attachment of an incoherent electron also induces such coherent dynamics. However, these processes are resonant and occur for projectiles with a specific energy. Here we present the most general scenario of non-resonant inelastic electron scattering inducing such a quantum coherence in molecular dynamics. The ion-pair formation (H+ + H─) that proceeds after the electron impact excitation of H2 shows a forward-backward asymmetry about the incoming electron beam. Simultaneous transfer of multiple angular momentum quanta during the electron collision induces the underlying coherence in the system. The non-resonant nature of this process makes this effect generic and points to its possible prevalent role in particle collision processes, including electron-induced chemistry.
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Affiliation(s)
- Akshay Kumar
- Tata Institute of Fundamental Research, Colaba Mumbai, 400005, India
| | - Suvasis Swain
- Tata Institute of Fundamental Research, Colaba Mumbai, 400005, India
- Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP) - UMR 6252 - Normandie Université, ENSICAEN, UNICAEN, CEA, CNRS, 14000, Caen, France
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7
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Dunand A, Minissale M, Angot T, Bisson R. Flux dependence of helium retention in clean W(110): experimental evidence for He self-trapping. NUCLEAR MATERIALS AND ENERGY 2022. [DOI: 10.1016/j.nme.2022.101324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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8
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BASALGETE R, Torres-Díaz D, Lafosse A, Amiaud L, Féraud G, Jeseck P, Philippe L, Michaut X, Fillion JH, Bertin M. Indirect X-ray photodesorption of 15N 2 and 13CO from mixed and layered ices. J Chem Phys 2022; 157:084308. [DOI: 10.1063/5.0100014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
X-ray photodesorption yields of 15N2 and 13CO are derived as a function of the incident photon energy near the N (~ 400 eV) and O K-edge (~ 500 eV) for pure 15N2 ice and mixed 13CO:15N2 ices. The photodesorption spectra from the mixed ices reveal an indirect desorption mechanism for which the desorption of 15N2 and 13CO is triggered by the photo-absorption of respectively 13CO and 15N2. This mechanism is confirmed by the X-ray photodesorption of 13CO from a layered 13CO/15N2 ice irradiated at 401 eV, on the N 1s -> π* transition of 15N2. This latter experiment enables to quantify the relevant depth involved in the indirect desorption process, which is found to be 30 - 40 ML in that case. This value is further related to the energy transport of Auger electrons emitted from the photo-absorbing 15N2molecules that scatter towards the ice surface, inducing the desorption of 13CO. The photodesorption yields corrected from the energy that can participate to the desorption process (expressed in molecules desorbed by eV deposited) do not depend on the photon energy hence neither on the photo-absorbing molecule nor on its state after Auger decay. This demonstrates that X-ray induced electron stimulated desorption (XESD), mediated by Auger scattering, is the dominant process explaining the desorption of 15N2 and 13CO from the ices studied in this work.
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Affiliation(s)
| | | | - Anne Lafosse
- Chemistry Department, University Paris-Sud, France
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9
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Perspectives of Gas Phase Ion Chemistry: Spectroscopy and Modeling. CONDENSED MATTER 2022. [DOI: 10.3390/condmat7030046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The study of ions in the gas phase has a long history and has involved both chemists and physicists. The interplay of their competences with the use of very sophisticated commercial and/or homemade instrumentations and theoretical models has improved the knowledge of thermodynamics and kinetics of many chemical reactions, even if still many stages of these processes need to be fully understood. The new technologies and the novel free-electron laser facilities based on plasma acceleration open new opportunities to investigate the chemical reactions in some unrevealed fundamental aspects. The synchrotron light source can be put beside the FELs, and by mass spectrometric techniques and spectroscopies coupled with versatile ion sources it is possible to really change the state of the art of the ion chemistry in different areas such as atmospheric and astro chemistry, plasma chemistry, biophysics, and interstellar medium (ISM). In this manuscript we review the works performed by a joint combination of the experimental studies of ion–molecule reactions with synchrotron radiation and theoretical models adapted and developed to the experimental evidence. The review concludes with the perspectives of ion–molecule reactions by using FEL instrumentations as well as pump probe measurements and the initial attempt in the development of more realistic theoretical models for the prospective improvement of our predictive capability.
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10
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Holste K, Dietz P, Scharmann S, Keil K, Henning T, Zschätzsch D, Reitemeyer M, Nauschütt B, Kiefer F, Kunze F, Zorn J, Heiliger C, Joshi N, Probst U, Thüringer R, Volkmar C, Packan D, Peterschmitt S, Brinkmann KT, Zaunick HG, Thoma MH, Kretschmer M, Leiter HJ, Schippers S, Hannemann K, Klar PJ. Ion thrusters for electric propulsion: Scientific issues developing a niche technology into a game changer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:061101. [PMID: 32611046 DOI: 10.1063/5.0010134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
The transition from old space to new space along with increasing commercialization has a major impact on space flight, in general, and on electric propulsion (EP) by ion thrusters, in particular. Ion thrusters are nowadays used as primary propulsion systems in space. This article describes how these changes related to new space affect various aspects that are important for the development of EP systems. Starting with a historical overview of the development of space flight and of the technology of EP systems, a number of important missions with EP and the underlying technologies are presented. The focus of our discussion is the technology of the radio frequency ion thruster as a prominent member of the gridded ion engine family. Based on this discussion, we give an overview of important research topics such as the search for alternative propellants, the development of reliable neutralizer concepts based on novel insert materials, as well as promising neutralizer-free propulsion concepts. In addition, aspects of thruster modeling and requirements for test facilities are discussed. Furthermore, we address aspects of space electronics with regard to the development of highly efficient electronic components as well as aspects of electromagnetic compatibility and radiation hardness. This article concludes with a presentation of the interaction of EP systems with the spacecraft.
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Affiliation(s)
- K Holste
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - P Dietz
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - S Scharmann
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - K Keil
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - T Henning
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - D Zschätzsch
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - M Reitemeyer
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - B Nauschütt
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - F Kiefer
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - F Kunze
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - J Zorn
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - C Heiliger
- Institute of Theoretical Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - N Joshi
- Institute of Theoretical Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - U Probst
- Department of Electrical Engineering, University of Applied Sciences, Wiesenstr. 14, 35390 Giessen, Germany
| | - R Thüringer
- Department of Electrical Engineering, University of Applied Sciences, Wiesenstr. 14, 35390 Giessen, Germany
| | - C Volkmar
- Department of Electrical Engineering, University of Applied Sciences, Wiesenstr. 14, 35390 Giessen, Germany
| | | | | | - K-T Brinkmann
- Institute of Experimental Physics II, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - H-G Zaunick
- Institute of Experimental Physics II, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - M H Thoma
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - M Kretschmer
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - H J Leiter
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - S Schippers
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - K Hannemann
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - P J Klar
- Institute of Experimental Physics I, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
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11
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Wolff W, Rudek B, da Silva LA, Hilgers G, Montenegro EC, Homem MGP. Absolute ionization and dissociation cross sections of tetrahydrofuran: Fragmentation-ion production mechanisms. J Chem Phys 2019. [DOI: 10.1063/1.5115403] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Affiliation(s)
- W. Wolff
- Instituto de Física, Universidade Federal do Rio de Janeiro, 21941-972, Rio de Janeiro, RJ, Brazil
| | - B. Rudek
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig, Germany
| | - L. A. da Silva
- Departamento de Química, Universidade Federal de São Carlos, 13565-905, São Carlos, SP, Brazil
| | - G. Hilgers
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig, Germany
| | - E. C. Montenegro
- Instituto de Física, Universidade Federal do Rio de Janeiro, 21941-972, Rio de Janeiro, RJ, Brazil
| | - M. G. P. Homem
- Departamento de Química, Universidade Federal de São Carlos, 13565-905, São Carlos, SP, Brazil
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12
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Huber SE, Mauracher A, Süß D, Sukuba I, Urban J, Borodin D, Probst M. Total and partial electron impact ionization cross sections of fusion-relevant diatomic molecules. J Chem Phys 2019; 150:024306. [PMID: 30646716 DOI: 10.1063/1.5063767] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We report calculations of total (and absolute) electron-impact ionization cross sections (EICSs) for the fusion-relevant diatomic molecular species BeH, BeN, BeO, WH, WBe, WN, WO, O2, and N2 by means of the Deutsch-Märk and the binary-encounter-Bethe methods in the energy range from threshold to 10 keV. In addition, we discuss an empirical scheme to estimate partial cross sections from the total ones based on reaction energetics and empirical threshold laws and explore its accuracy by assessing available experimental data on total and partial EICSs. Finally, we also report parameters obtained by fitting the calculated cross sections to an expression commonly used in fusion edge plasma modeling.
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Affiliation(s)
- Stefan E Huber
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Andreas Mauracher
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Daniel Süß
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Ivan Sukuba
- Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, 84248 Bratislava, Slovakia
| | - Jan Urban
- Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, 84248 Bratislava, Slovakia
| | - Dmitry Borodin
- Institute of Energy and Climate Research, Forschungszentrum Juelich, 52428 Juelich, Germany
| | - Michael Probst
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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13
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Gudmundsson JT, Lundin D, Brenning N, Raadu MA, Huo C, Minea TM. An ionization region model of the reactive Ar/O2high power impulse magnetron sputtering discharge. ACTA ACUST UNITED AC 2016. [DOI: 10.1088/0963-0252/25/6/065004] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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14
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Evaluation of State-Resolved Reaction Probabilities and Their Application in Population Models for He, H, and H2. ATOMS 2016. [DOI: 10.3390/atoms4040026] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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15
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Sigaud L, de Jesus VLB, Ferreira N, Montenegro EC. A novel double-focusing time-of-flight mass spectrometer for absolute recoil ion cross sections measurements. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:083112. [PMID: 27587105 DOI: 10.1063/1.4961664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this work, the inclusion of an Einzel-like lens inside the time-of-flight drift tube of a standard mass spectrometer coupled to a gas cell-to study ionization of atoms and molecules by electron impact-is described. Both this lens and a conical collimator are responsible for further focalization of the ions and charged molecular fragments inside the spectrometer, allowing a much better resolution at the time-of-flight spectra, leading to a separation of a single mass-to-charge unit up to 100 a.m.u. The procedure to obtain the overall absolute efficiency of the spectrometer and micro-channel plate detector is also discussed.
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Affiliation(s)
- L Sigaud
- Instituto de Física, Universidade Federal Fluminense (UFF), 24210-346 Niterói, RJ, Brazil
| | - V L B de Jesus
- Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro (IFRJ), Campus Nilópolis, 26530-060 Nilópolis, RJ, Brazil
| | - Natalia Ferreira
- CEFET/RJ, Unidade Maracanã, 20271-110 Rio de Janeiro, RJ, Brazil
| | - E C Montenegro
- Instituto de Física, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68528, 21941-972 Rio de Janeiro, RJ, Brazil
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16
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Zammit MC, Savage JS, Fursa DV, Bray I. Complete Solution of Electronic Excitation and Ionization in Electron-Hydrogen Molecule Scattering. PHYSICAL REVIEW LETTERS 2016; 116:233201. [PMID: 27341229 DOI: 10.1103/physrevlett.116.233201] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Indexed: 06/06/2023]
Abstract
The convergent close-coupling method has been used to solve the electron-hydrogen molecule scattering problem in the fixed-nuclei approximation. Excellent agreement with experiment is found for the grand total, elastic, electronic-excitation, and total ionization cross sections from the very low to the very high energies. This shows that for the electronic degrees of freedom the method provides a complete treatment of electron scattering on molecules as it does for atoms.
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Affiliation(s)
- Mark C Zammit
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- Curtin Institute for Computation and Department of Physics, Astronomy and Medical Radiation Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Jeremy S Savage
- Curtin Institute for Computation and Department of Physics, Astronomy and Medical Radiation Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Dmitry V Fursa
- Curtin Institute for Computation and Department of Physics, Astronomy and Medical Radiation Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Igor Bray
- Curtin Institute for Computation and Department of Physics, Astronomy and Medical Radiation Sciences, Curtin University, Perth, Western Australia 6102, Australia
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17
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Liu N, Xu X, Pang R, Raman PS, Khursheed A, van Kan JA. Brightness measurement of an electron impact gas ion source for proton beam writing applications. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02A903. [PMID: 26931964 DOI: 10.1063/1.4932005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We are developing a high brightness nano-aperture electron impact gas ion source, which can create ion beams from a miniature ionization chamber with relatively small virtual source sizes, typically around 100 nm. A prototype source of this kind was designed and successively micro-fabricated using integrated circuit technology. Experiments to measure source brightness were performed inside a field emission scanning electron microscope. The total output current was measured to be between 200 and 300 pA. The highest estimated reduced brightness was found to be comparable to the injecting focused electron beam reduced brightness. This translates into an ion reduced brightness that is significantly better than that of conventional radio frequency ion sources, currently used in single-ended MeV accelerators.
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Affiliation(s)
- N Liu
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore 117542
| | - X Xu
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore 117542
| | - R Pang
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore 117542
| | - P Santhana Raman
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore 117542
| | - A Khursheed
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583
| | - J A van Kan
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore 117542
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18
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Vojnović M, Popović M, Ristić M, Vićić M, Poparić G. Rate coefficients for electron impact excitation of N2. Chem Phys 2015. [DOI: 10.1016/j.chemphys.2015.09.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Du C, Mo J, Li H. Renewable Hydrogen Production by Alcohols Reforming Using Plasma and Plasma-Catalytic Technologies: Challenges and Opportunities. Chem Rev 2014; 115:1503-42. [DOI: 10.1021/cr5003744] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- ChangMing Du
- Guangdong Provincial Key
Laboratory of Environmental Pollution Control and Remediation Technology,
School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - JianMin Mo
- Guangdong Provincial Key
Laboratory of Environmental Pollution Control and Remediation Technology,
School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - HongXia Li
- Guangdong Provincial Key
Laboratory of Environmental Pollution Control and Remediation Technology,
School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
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20
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Wolff W, Luna H, Sigaud L, Tavares AC, Montenegro EC. Absolute total and partial dissociative cross sections of pyrimidine at electron and proton intermediate impact velocities. J Chem Phys 2014; 140:064309. [PMID: 24527917 DOI: 10.1063/1.4864322] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Absolute total non-dissociative and partial dissociative cross sections of pyrimidine were measured for electron impact energies ranging from 70 to 400 eV and for proton impact energies from 125 up to 2500 keV. MOs ionization induced by coulomb interaction were studied by measuring both ionization and partial dissociative cross sections through time of flight mass spectrometry and by obtaining the branching ratios for fragment formation via a model calculation based on the Born approximation. The partial yields and the absolute cross sections measured as a function of the energy combined with the model calculation proved to be a useful tool to determine the vacancy population of the valence MOs from which several sets of fragment ions are produced. It was also a key point to distinguish the dissociation regimes induced by both particles. A comparison with previous experimental results is also presented.
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Affiliation(s)
- Wania Wolff
- Instituto de Física, Universidade Federal do Rio de Janeiro, PO 68528, 21941-972 Rio de Janeiro, RJ, Brazil
| | - Hugo Luna
- Instituto de Física, Universidade Federal do Rio de Janeiro, PO 68528, 21941-972 Rio de Janeiro, RJ, Brazil
| | - Lucas Sigaud
- Instituto de Física, Universidade Federal do Rio de Janeiro, PO 68528, 21941-972 Rio de Janeiro, RJ, Brazil
| | - Andre C Tavares
- Departamento de Física, Pontificia Universidade Católica do Rio de Janeiro, PO 38071, Rua Marquês de São Vicente 225, 22453-900 Rio de Janeiro, RJ, Brazil
| | - Eduardo C Montenegro
- Instituto de Física, Universidade Federal do Rio de Janeiro, PO 68528, 21941-972 Rio de Janeiro, RJ, Brazil
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21
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Sigaud L, Ferreira N, Montenegro EC. Absolute cross sections for O2 dication production by electron impact. J Chem Phys 2013; 139:024302. [DOI: 10.1063/1.4812779] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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Engmann S, Stano M, Papp P, Brunger MJ, Matejčík Š, Ingólfsson O. Absolute cross sections for dissociative electron attachment and dissociative ionization of cobalt tricarbonyl nitrosyl in the energy range from 0 eV to 140 eV. J Chem Phys 2013; 138:044305. [DOI: 10.1063/1.4776756] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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23
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Bull JN, Lee JWL, Vallance C. Quantification of ions with identical mass-to-charge (m/z) ratios by velocity-map imaging mass spectrometry. Phys Chem Chem Phys 2013; 15:13796-800. [DOI: 10.1039/c3cp52219a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Loison JC, Rayez MT, Rayez JC, Gratien A, Morajkar P, Fittschen C, Villenave E. Gas-Phase Reaction of Hydroxyl Radical with Hexamethylbenzene. J Phys Chem A 2012. [DOI: 10.1021/jp307568c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jean-Christophe Loison
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Marie-Thérèse Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Jean-Claude Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Aline Gratien
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Pranay Morajkar
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Christa Fittschen
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Eric Villenave
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
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25
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Daranlot J, Hickson KM, Loison JC, Méreau R, Caralp F, Forst W, Bergeat A. Gas-phase kinetics of the hydroxyl radical reaction with allene: absolute rate measurements at low temperature, product determinations, and calculations. J Phys Chem A 2012; 116:10871-81. [PMID: 23126232 DOI: 10.1021/jp304831x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The gas phase reaction of the hydroxyl radical with allene has been studied theoretically and experimentally in a continuous supersonic flow reactor over the range 50 ≤ T/K ≤ 224. This reaction has been found to exhibit a negative temperature dependence over the entire temperature range investigated, varying between (0.75 and 5.0) × 10(-11) cm(3) molecule(-1) s(-1). Product formation from the reaction of OH and OD radicals with allene (C(3)H(4)) has been investigated in a fast flow reactor through time-of-flight mass spectrometry, at pressures between 0.8 and 2.4 Torr. The branching ratios for adduct formation (C(3)H(4)OH) in this pressure range are found to be equal to 34 ± 16% and 48 ± 16% for the OH and OD + allene reactions, respectively, the only other channel being the formation of CH(3) or CH(2)D + H(2)CCO (ketene). Moreover, the rate constant for the OD + C(3)H(4) reaction is also found to be 1.4 times faster than the rate constant for the OH + C(3)H(4) reaction at 1.5 Torr and at 298 K. The experimental results and implications for atmospheric chemistry have been rationalized by quantum chemical and RRKM calculations.
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26
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Vibrationally resolved ionization cross sections for the ground state and electronically excited states of the hydrogen molecule. Chem Phys 2011. [DOI: 10.1016/j.chemphys.2011.10.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Thissen R, Witasse O, Dutuit O, Wedlund CS, Gronoff G, Lilensten J. Doubly-charged ions in the planetary ionospheres: a review. Phys Chem Chem Phys 2011; 13:18264-87. [PMID: 21931881 DOI: 10.1039/c1cp21957j] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This paper presents a review of the current knowledge on the doubly-charged atomic and molecular positive ions in the planetary atmospheres of the Solar System. It is focused on the terrestrial planets which have a dense atmosphere of N(2) or CO(2), i.e. Venus, the Earth and Mars, but also includes Titan, the largest satellite of Saturn, which has a dense atmosphere composed mainly of N(2) and a few percent of methane. Given the composition of these neutral atmospheres, the following species are considered: C(++), N(++), O(++), CH(4)(++), CO(++), N(2)(++), NO(++), O(2)(++), Ar(++) and CO(2)(++). We first discuss the status of their detection in the atmospheres of planets. Then, we provide a comprehensive review of their complex and original photochemistry, production and loss processes. Synthesis tables are provided for those ions, while a discussion on individual species is also provided. Methods for detecting doubly-charged ions in planetary atmospheres are presented, namely with mass-spectrometry, remote sensing and fine plasma density measurements. A section covers some original applications, like the possible effect of the presence of doubly-charged ions on the escape of an atmosphere, which is a key topic of ongoing planetary exploration, related to the evolution of a planet. The results of models, displayed in a comparative way for Venus, Earth, Mars and Titan, are discussed, as they can predict the presence of doubly-charged ions and will certainly trigger new investigations. Finally we give our view concerning next steps, challenges and needs for future studies, hoping that new scientific results will be achieved in the coming years and feed the necessary interdisciplinary exchanges amongst different scientific communities.
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Affiliation(s)
- Roland Thissen
- Institut de Planétologie et d'Astrophysique de Grenoble, UJF-Grenoble 1/CNRS-INSU, UMR 5274, Grenoble, F-38041, France.
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28
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Energy deposition by a 106Ru/106Rh eye applicator simulated using LEPTS, a low-energy particle track simulation. Appl Radiat Isot 2011; 69:1198-204. [DOI: 10.1016/j.apradiso.2011.04.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 04/18/2011] [Accepted: 04/19/2011] [Indexed: 11/24/2022]
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29
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Carrasco E, Jiménez-Redondo M, Tanarro I, Herrero VJ. Neutral and ion chemistry in low pressure dc plasmas of H2/N2 mixtures: routes for the efficient production of NH3 and NH4+. Phys Chem Chem Phys 2011; 13:19561-72. [DOI: 10.1039/c1cp22284h] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Loison JC, Daranlot J, Bergeat A, Caralp F, Mereau R, Hickson KM. Gas-Phase Kinetics of Hydroxyl Radical Reactions with C3H6 and C4H8: Product Branching Ratios and OH Addition Site-Specificity. J Phys Chem A 2010; 114:13326-36. [DOI: 10.1021/jp107217w] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jean-Christophe Loison
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Julien Daranlot
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Astrid Bergeat
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Françoise Caralp
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Raphaël Mereau
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Kevin M. Hickson
- Institut des Sciences Moléculaires, CNRS UMR 5255, Université Bordeaux I, 351 Cours de la Libération, 33405 Talence cedex, France
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31
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Galand M, Moore L, Charnay B, Mueller-Wodarg I, Mendillo M. Solar primary and secondary ionization at Saturn. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013981] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Marina Galand
- Department of Physics; Imperial College London; London UK
| | - Luke Moore
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | | | | | - Michael Mendillo
- Center for Space Physics; Boston University; Boston Massachusetts USA
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32
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Shiki S, Ukibe M, Sato Y, Tomita S, Hayakawa S, Ohkubo M. Kinetic-energy-sensitive mass spectrometry for separation of different ions with the same m/z value. JOURNAL OF MASS SPECTROMETRY : JMS 2008; 43:1686-1691. [PMID: 18698555 DOI: 10.1002/jms.1459] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A double-focusing mass spectrometer (MS) equipped with a superconducting-tunnel-junction (STJ) detector has been applied to measure relative ionization cross-sections for the production of ions that are accompanied by different ion species with the same mass-to-charge (m/z) value. The STJ detector fabricated for this study enables kinetic energy (E) measurement of incoming individual ions at a counting rate of up to approximately 100 k ions/s and an energy resolution (DeltaE/E) of 15%. Both high counting rate and high-energy resolution are necessary to independently determine both m and z and not the m/z value only in ion-counting MS experiments. Ions such as (14)N(2) (2+) and (14)N(+) with the same m/z value can be clearly discriminated using a kinetic-energy-sensitive MS. This fine discrimination capability allows direct determination of relative ionization cross-sections of the homonuclear diatomic ions (14)N(2) (2+)/(14)N(2) (+) and (16)O(2) (2+)/(16)O(2) (+), which are difficult to measure due to the strong interference by the signals of their dissociated atomic ions with noticeably large ionization cross-sections. The new instrument requires no low-abundance heteronuclear diatomic molecules of the forms (14)N(15)N or (16)O(17)O to carry out ionization studies and thus, is expected to be useful in fields such as atmospheric science, interstellar science, or plasma physics.
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Affiliation(s)
- Shigetomo Shiki
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8568, Japan
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33
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Benedikt J, Flötgen C, Kussel G, Raball V, Keudell AV. Etching ofBacillus atrophaeusby oxygen atoms, molecules and argon ions. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/133/1/012012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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34
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Muñoz A, Oiler JC, Blanco F, Gorfinkiel JD, Limão-Vieira P, Maira-Vidal A, Borge MJG, Tengblad O, Huerga C, Téllez M, García G. Energy deposition model based on electron scattering cross section data from water molecules. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/133/1/012002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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35
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36
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Franceschi P, Ascenzi D, Tosi P, Thissen R, Zabka J, Roithová J, Ricketts CL, De Simone M, Coreno M. Dissociative double photoionization of N2 using synchrotron radiation: Appearance energy of the N2+ dication. J Chem Phys 2007; 126:134310. [PMID: 17430035 DOI: 10.1063/1.2714521] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Photoionization cross sections for the production of the doubly charged ion N2+ from N2 have been measured by means of synchrotron radiation in the photon energy range from 50 to 110 eV. The appearance energy for N2+ has been determined as 55.2+/-0.2 eV, i.e., about 1.3 eV higher than the spectroscopic dissociation limit leading to the charge asymmetric dissociation channel N2+(2P)+N(4S) at 53.9 eV. The onset of a second threshold at 59.9+/-0.2 eV is detected and the energy dependence of photoion intensities near the threshold regions is interpreted in terms of the Wannier theory. The production of the N2+ dication is discussed in terms of direct and indirect mechanisms for dissociative charge asymmetric photoionization and by comparison with the potential energy curves of the intermediate N(2)2+ dication. Experimental evidences for the opening of the Coulomb explosion channel N2++N+ at high photon energies are provided by measuring the kinetic energy release spectra of N2+ fragments at selected photon energies.
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Affiliation(s)
- Pietro Franceschi
- Dipartimento di Fisica, Università di Trento, via Sommarive 14, 38050 Povo (TN), Italy.
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37
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Soloshenko IA, Tsiolko VV, Pogulyai SS, Terent’eva AG, Bazhenov VY, Shchedrin AI, Ryabtsev AV, Kuzmichev AI. Concentrations of active species in a bulk barrier discharge in a plasmochemical reactor. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2006. [DOI: 10.1134/s0036024406130139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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38
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Shemansky DE. Evaluation of electron impact excitation of N2X1Σg+(0) into the N2+X2Σg+(v), A2Πu(v), and B2Σu+(v) states. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005ja011062] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Wang WG, Xu Y, Yang XF, Wang WC, Zhu AM. Determination of atomic hydrogen in non-thermal hydrogen plasmas by means of molecular beam threshold ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:1159-1166. [PMID: 15803516 DOI: 10.1002/rcm.1906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Atomic hydrogen plays important roles in chemical vapor deposition of functional materials, plasma etching and new approaches to chemical synthesis of hydrogen-containing compounds. The present work reports experimental determinations of atomic hydrogen near the grounded electrode in medium-pressure dielectric barrier discharge hydrogen plasmas by means of molecular beam threshold ionization mass spectrometry (MB-TIMS). At certain discharge conditions (a.c. frequency of 24 kHz, 28 kV of peak-to-peak voltage), the measured hydrogen dissociation fraction is decreased from approximately 0.83% to approximately 0.14% as the hydrogen pressure increases from 2.0 to 14.0 Torr. A simulation method for extraction of the approximate electron beam energy distribution function in the mass spectrometer ionizer and a semi-quantitative approach to calibrate the mass discrimination effect caused by the supersonic beam formation and the mass spectrometer measurement are reported.
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Affiliation(s)
- Wei-Guo Wang
- Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian, China
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Higaki H, Kuroda N, Yoshiki Franzen K, Wang Z, Hori M, Mohri A, Komaki K, Yamazaki Y. Radial compression of protons and H3+ ions in a multiring trap for the production of ultralow energy antiproton beams. Phys Rev E 2004; 70:026501. [PMID: 15447603 DOI: 10.1103/physreve.70.026501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2003] [Indexed: 11/07/2022]
Abstract
Radial compression of a proton cloud was performed in a multiring trap which was designed to trap and cool a large number of antiprotons for the production of low-energy ( 10-1000 eV ) antiproton beams. The resonance frequency for the radial compression was almost constant from 3 x 10(5) to 3 x 10(6) protons. The collision process of the trapped protons was also investigated to estimate the energy of the protons inside the trap. This technique will be applied to the ASACUSA experiment at the antiproton decelerator, CERN, to extract ultraslow antiprotons with good emittance.
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Affiliation(s)
- H Higaki
- Institute of Physics, University of Tokyo, 3-8-1, Komaba, Meguro, Tokyo 153-8902 Japan
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Lindsay BG, McDonald KF, Yu WS, Stebbings RF, Yousif FB. Electron-impact ionization of CCl4 and CCl2F2. J Chem Phys 2004; 121:1350-6. [PMID: 15260678 DOI: 10.1063/1.1761055] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Absolute partial and total cross sections for electron-impact ionization of CCl4 and CCl2F2 are reported for electron energies from threshold to 1000 eV. The product ions are mass analyzed using a time-of-flight mass spectrometer and detected with a position-sensitive detector whose output demonstrates that all product ion species are collected with equal efficiency irrespective of their initial kinetic energies. Data are presented for production of CCl3(+), CCl2(+), CCl+, C+, Cl2(+), and CCl3(2+) from CCl4; and for production of CCl(2)F+, CClF2(+), CClF(+), (CCl+ + CF2(+)), Cl+, CF+, F+, and C+ from CCl2F2. Data are also reported for formation of (CCl2(+),Cl+) and (CCl+, Cl+) ion pairs from CCl4. The total cross section for each target is obtained as the sum of the partial cross sections. The overall uncertainty in the absolute cross sections for most of the singly charged ions is +/- 5-7 %. The present partial cross sections for lighter fragment ions are found to be considerably greater than had been previously reported but the most recent total cross section measurements agree well with those reported here. Neither the binary-encounter-Bethe theory nor the Deutsch-Mark theory reproduces the experimental cross sections correctly for both targets.
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Affiliation(s)
- B G Lindsay
- Department of Physics and Astronomy and Rice Quantum Institute, Rice University, Houston, Texas 77005-1892, USA.
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Fox JL. Response of the Martian thermosphere/ionosphere to enhanced fluxes of solar soft X rays. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004ja010380] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ekey R, McCormack E. A planar jet expansion discharge source of molecular afterglow emission. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.09.129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Lindsay BG, Rejoub R, Stebbings RF. Absolute cross sections for electron-impact ionization of N2O, H2S, and CS2 from threshold to 1000 eV. J Chem Phys 2003. [DOI: 10.1063/1.1556613] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Rejoub R, Morton CD, Lindsay BG, Stebbings RF. Electron-impact ionization of the simple alcohols. J Chem Phys 2003. [DOI: 10.1063/1.1531631] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Rejoub R, Lindsay BG, Stebbings RF. Electron-impact ionization of the methyl halides. J Chem Phys 2002. [DOI: 10.1063/1.1506152] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Jiao CQ, DeJoseph CA, Garscadden A. Absolute cross sections for electron impact ionization of NO2. J Chem Phys 2002. [DOI: 10.1063/1.1480867] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Huo WM, Tarnovsky V, Becker KH. Total electron-impact ionization cross-sections of CFx and NFx (x=1–3). Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00633-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Hanel G, Gstir B, Fiegele T, Hagelberg F, Becker K, Scheier P, Snegursky A, Märk TD. Isotope effects in the electron impact ionization of H2/D2, H2O/D2O, and C6H6/C6D6 near threshold. J Chem Phys 2002. [DOI: 10.1063/1.1428341] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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