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Recoil Ions From Close 20-Kev H+ Collisions With O2, Co, Co2, And Ne, Akio Itoh, M. Eugene Rudd
Recoil Ions From Close 20-Kev H+ Collisions With O2, Co, Co2, And Ne, Akio Itoh, M. Eugene Rudd
M. Eugene Rudd Publications
Recoil ions ejected at 70° from 20-keV proton collisions with O2, CO, CO2, and Ne were analyzed by an electrostatic analyzer. For the molecular targets, only singly ionized ions of oxygen or carbon were detected while in the spectrum of neon ions, Ne+ and Ne2+ were both observed. The absence of O2+, CO+, and CO2+ is due to the fact that the recoil ions detected in this experiment result only from very close collisions with one of the atoms in the molecule resulting in dissociation. A possible …
Recoil-Ion Production From Zero-Impact-Parameter H+-Ar And H+-Kr Collisions At 20-70 Kev, Akio Itoh, M. Eugene Rudd
Recoil-Ion Production From Zero-Impact-Parameter H+-Ar And H+-Kr Collisions At 20-70 Kev, Akio Itoh, M. Eugene Rudd
M. Eugene Rudd Publications
Recoil ions emitted at 70° from H+-Ar and at 50° and 70° from H+-Kr collisions at 20-70 keV were analyzed by an electrostatic spectrometer. Ions selected in this way result from collisions at very small, essentially zero, impact parameters. Charge states up to 6 + were identified in the spectrum. The cross section for each charge state was measured. The data indicate that these close collisions produce a larger fraction of ions in high charge states than more distant collisions.
Differential Cross Sections For Ionization Of Water Vapor By High-Velocity Bare Ions And Electrons, J. H. Miller, W. E. Wilson, S. T. Manson, M. Eugene Rudd
Differential Cross Sections For Ionization Of Water Vapor By High-Velocity Bare Ions And Electrons, J. H. Miller, W. E. Wilson, S. T. Manson, M. Eugene Rudd
M. Eugene Rudd Publications
A semiempirical model of single differential cross sections (SDCS) for ionization of water vapor by fast electrons and bare ions is presented. At low secondary-electron energy, the model is based on an asymptotic expansion of the first Born approximation with coefficients, that are independent of projectile properties, evaluated from experimental photoabsorption and protonimpact ionization data. As the secondary-electron energy increases, the model converges to a binary-encounter approximation. Comparisons with measured differential, total, and dissociative cross sections for ionization of water by fast electrons are used to test the model. For primary electrons with energy greater than about 500 eV, agreement …
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. Ii. 15-150-Kev Proton Impact, M. A. Bolorizadeh, M. Eugene Rudd
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. Ii. 15-150-Kev Proton Impact, M. A. Bolorizadeh, M. Eugene Rudd
M. Eugene Rudd Publications
Absolute values of cross sections for electron ejection by protons of 15- 150 keV energy have been measured as a function of the angle and energy of the electrons. The range of angles was 10° to 160° and the electron energy range was 1-300 eV. The doubly differential cross sections were also integrated over energy or angle to obtain singly differential and total cross sections and also average ejected electron energies. Good agreement is obtained with Senger's DDCS-MT (doubly differential cross section-mixed treatment) theoretical treatment using the Salin factor.
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. Iii. 20- 150-Kev Neutral-Hydrogen Impact, M. A. Bolorizadeh, M. Eugene Rudd
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. Iii. 20- 150-Kev Neutral-Hydrogen Impact, M. A. Bolorizadeh, M. Eugene Rudd
M. Eugene Rudd Publications
Absolute values of cross sections for electron production in collisions of neutral hydrogen atoms of 20-150 keV energy with water vapor molecules have been measured as a function of the ejection energy and angle. The range of angles was 10° to 160° and the electron energy range was 1-300 eV. The doubly differential cross sections were integrated over angle and/or energy to obtain singly differential cross sections, total electron production cross sections, and average energies of ejection. The angular distribution of the electron loss peak was found to have some features in common with the cross section for elastic scattering …
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. I. 50-2000-Ev Electron Impact, M. A. Bolorizadeh, M. Eugene Rudd
Angular And Energy Dependence Of Cross Sections For Ejection Of Electrons From Water Vapor. I. 50-2000-Ev Electron Impact, M. A. Bolorizadeh, M. Eugene Rudd
M. Eugene Rudd Publications
We have measured the angular and energy distribution of the absolute cross sections for ejection of electrons from water vapor by electrons incident at 50-2000 eV. The angular range was 15° to 150° and the range of secondary electron energies was from 2 eV to an energy equal to the primary energy minus the first ionization potential. Electron energies were analyzed with a parallel-plate electrostatic analyzer with a resolution of 1.1%. Generally good agreement is obtained with the data of Opal et al. [J. Chem. Phys. 55, 4100 (1971)l at 500 eV except at the extremes of their angular range. …
Ionization Cross Sections For 10-300-Kev/U And Electron-Capture Cross Sections For 5- 150-Kev/U 3He2+ Ions In Gases, M. Eugene Rudd, T. V. Goffe, A. Itoh
Ionization Cross Sections For 10-300-Kev/U And Electron-Capture Cross Sections For 5- 150-Kev/U 3He2+ Ions In Gases, M. Eugene Rudd, T. V. Goffe, A. Itoh
M. Eugene Rudd Publications
Cross sections for production of positive and negative charge for 10-300-keV/u He2+ ions on He, Ne, Ar, Kr, H2, N2, CO, O2, CH4, N2O, and C02 were measured by the transverse-field method. Single- and double-electron-capture cross sections at 5-150 keV/u for the same targets were measured by the method of deflection of different charge-state components of the beam after passing through a known length of target gas. A secondary-emission detector was used to detect the neutral component of the beam. A small least-squares adjustment of the cross sections …
Electron Production In Proton Collisions: Total Cross Sections, M. Eugene Rudd, Y-K. Kim, D. H. Madison, J. W. Gallagher
Electron Production In Proton Collisions: Total Cross Sections, M. Eugene Rudd, Y-K. Kim, D. H. Madison, J. W. Gallagher
M. Eugene Rudd Publications
Existing data on the ionization of neutral atoms and molecules by proton impact are reviewed, and electron production cross-section data are collected. The three major experimental methods are discussed and possible sources of error identified. Some theoretical cross sections are discussed, and well-established methods of relating them to measured cross sections are reviewed. A mathematical equation is fitted to the weighted experimental data for each target, and these fits are adjusted to be consistent with appropriate theoretical calculations and with electron impact and photoionization data. Recommended values of total cross sections for proton-impact ionization are given.
Cross Sections For Ionization Of Gases By 10-2000-Kev He+ Ions And For Electron Capture And Loss By 5-350-Kev He+ Ions, M. Eugene Rudd, T. V. Goff, A. Itoh, R. D. Dubois
Cross Sections For Ionization Of Gases By 10-2000-Kev He+ Ions And For Electron Capture And Loss By 5-350-Kev He+ Ions, M. Eugene Rudd, T. V. Goff, A. Itoh, R. D. Dubois
M. Eugene Rudd Publications
Cross sections for production of positive and negative charge for 10-2000-keV He+ ions on He, Ne, Ar, Kr, H2, N2, CO, O2, CH4, and CO2 were measured by the transverse-field method. Electron-capture and -loss cross sections for 5-350-keV He+ ions on the same targets were measured by the method of beam deflection of various charge states after passing through a known length of target gas. Secondary-emission detectors were used to detect neutral, singly charged, and doubly charged beam components. The equation σ+- σ- = σ10 …
Cross Sections For Ionization Of Water Vapor By 7-4000-Kev Protons, M. Eugene Rudd, T. V. Goffe, R. D. Dubois, L. H. Toburen
Cross Sections For Ionization Of Water Vapor By 7-4000-Kev Protons, M. Eugene Rudd, T. V. Goffe, R. D. Dubois, L. H. Toburen
M. Eugene Rudd Publications
Cross sections for production of electrons and positive ions by proton impact on water vapor have been measured from 7-4000 keV by the transverse-field method.
Multiple Ionization Of Rare Gases By H+ And He+ Impact, R. D. Dubois, L. H. Toburen, M. Eugene Rudd
Multiple Ionization Of Rare Gases By H+ And He+ Impact, R. D. Dubois, L. H. Toburen, M. Eugene Rudd
M. Eugene Rudd Publications
Absolute cross sections for multiple ionization (σq)of He, Ne, Ar, and Kr are presented for proton-impact energies between 10 and 4000 keV. Charge states up to 6 + are observed for Kr. The results are obtained by measuring relative yields of multiply charged ions with a time-of-flight spectrometer and normalizing to total ion-production cross sections σT= ∑qσq. The results are compared with existing proton- and electron-impact data. Relative multiple- to single-ionization cross-section ratios are also presented for He+ impact.
Cross Sections For Ionizaton Of Gases By 5-4000-Kev Protons And For Electron Capture By 5-150-Kev Protons, M. Eugene Rudd, R. D. Dubois, L. H. Toburen, C. A. Ratcliffe, T. V. Goffe
Cross Sections For Ionizaton Of Gases By 5-4000-Kev Protons And For Electron Capture By 5-150-Kev Protons, M. Eugene Rudd, R. D. Dubois, L. H. Toburen, C. A. Ratcliffe, T. V. Goffe
M. Eugene Rudd Publications
Using the parallel-plate-capacitor method and a capacitance manometer to determine pressures, total cross sections for the production of positive and negative charges were measured for 5-4000- keV-proton impact on He, Ne, Ar, Kr, Hz, N2, CO, 02, CH4, and C02. From these, ionization and electron-capture cross sections were obtained and fitted to semi-empirical equations describing the energy dependence in terms of a few parameters. At high energies very good agreement is obtained in the comparison of the ionization cross sections to earlier proton- and electron-impact measurements and with theoretical treatments where they …
Ionization By Low And Intermediate Energy Ion And Neutral Beams, M. Eugene Rudd
Ionization By Low And Intermediate Energy Ion And Neutral Beams, M. Eugene Rudd
M. Eugene Rudd Publications
One of the most important basic processes that take place in collisions of atomic systems is ionization resulting in the emission of electrons. A complete understanding of this process is complicated by the fact that electron emission can take place via a number of mechanisms, some of which are related. Simple measurements of the cross section for electron ejection as a function of projectile velocity does not usually provide enough information to unravel the various mechanisms. But cross sections which are differential in the angle and energy of the ejected electrons, which are now available for protons on a variety …
Angular And Energy Distribution Of Electrons From 15- To 150-Kev H0+He Collisions, M. Eugene Rudd, J. S. Risley, J. Fryar, R. G. Rolfes
Angular And Energy Distribution Of Electrons From 15- To 150-Kev H0+He Collisions, M. Eugene Rudd, J. S. Risley, J. Fryar, R. G. Rolfes
M. Eugene Rudd Publications
An electrostatic analyzer positioned at various angles has been used to measure absolute values of cross sections for electron production in collisions of neutral hydrogen atoms with helium as a function of the angle and energy of the ejected electrons. These cross sections are compared with corresponding ones for proton and electron impact to infer the mechanisms of electron production. A prominent peak in the energy distribution due to electron loss from the projectile occurs at an electron velocity equal to that of the projectile. At very low electron energies the similarity of the energy distribution to that due to …
Energy And Angular Distributions Of Secondary Electrons From 5-100-Kev-Proton Collisions With Hydrogen And Nitrogen Molecules, M. Eugene Rudd
Energy And Angular Distributions Of Secondary Electrons From 5-100-Kev-Proton Collisions With Hydrogen And Nitrogen Molecules, M. Eugene Rudd
M. Eugene Rudd Publications
Cross sections for the ejection of electrons from hydrogen and nitrogen by protons have been measured as a function of the energy and angle of ejection of the electrons at incident proton energies of 5-70 keV and 100 keV for hydrogen. The range of angles measured was 10-160° and the electron energy range was 1.5-300 eV. The doubly differential cross sections were also integrated over angle, over electron energy, or over both to obtain singly differential and total cross sections for electron production. Average electron energies were also calculated from the data. The angular distributions of electrons are peaked in …
Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. Ii. 100-500-Ev Electrons On Neon, Argon, Molecular Hydrogen, And Molecular Nitrogen, R. D. Dubois, M. Eugene Rudd
Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. Ii. 100-500-Ev Electrons On Neon, Argon, Molecular Hydrogen, And Molecular Nitrogen, R. D. Dubois, M. Eugene Rudd
M. Eugene Rudd Publications
Absolute doubly differential cross sections for secondary electron production by electron impact have been measured for static gas targets of neon, argon, hydrogen, and nitrogen. Electron impact energies were from 100 to 500 eV. An electrostatic analyzer was used to analyze secondary electrons with energies between 4 eV and the primary electron energy minus the first ionization potential of the target. Angles of emission were 10° to 150°. The present data agree well with the data of Opal, Beaty, and Peterson at 90° but, as was observed previously for helium, the agreement becomes increasingly poorer for larger and smaller angles. …
Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. I. 100- And 200-Ev Electrons On Helium, M. Eugene Rudd, R. D. Dubois
Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. I. 100- And 200-Ev Electrons On Helium, M. Eugene Rudd, R. D. Dubois
M. Eugene Rudd Publications
We have measured absolute values of the cross sections for ejection of electrons from helium gas by 100- and 200-eV electrons. These cross sections were measured for emission angles from 10° to 150° and for electron energies from 3 eV to a value equal to the primary energy minus the ionization potential. The measurements were made using a static-gas target and an electrostatic analyzer. The resulting cross sections agree reasonably well with those of Opal, Peterson, and Beaty near 90°, but show the need for an adjustment of their angular distributions. Comparison with Born-approximation calculations of Manson et al. at …
Energy And Angular Distribution Of Electrons Ejected From Argon By 5-Kev To 1.5-Mev Protons, T. L. Criswell, L. H. Toburen, M. Eugene Rudd
Energy And Angular Distribution Of Electrons Ejected From Argon By 5-Kev To 1.5-Mev Protons, T. L. Criswell, L. H. Toburen, M. Eugene Rudd
M. Eugene Rudd Publications
Cross sections, differential in emission energy and angle, have been measured for the ejection of electrons in collisions of H+ with argon gas targets. Incident-proton energies studied were from 5 keV to 1.5 MeV and electron emission angles ranged from 10° to 160°. Integration of the double-differential cross sections over emission angle and energy yield results in good agreement with direct measurement of total ionization cross sections. The electron distributions are compared to two plane-wave Born-approximation calculations, one using Hartree-Slater wave functions and the other using Hartree-Fock wave functions in the 3p-εd channel.
Review Of Quantum States Of Atoms, Molecules And Solids, M. Eugene Rudd
Review Of Quantum States Of Atoms, Molecules And Solids, M. Eugene Rudd
M. Eugene Rudd Publications
The subjects of atomic, molecular and solid-state physics have only rarely been treated at an advanced level in a single volume. The notable exception, of course, is John C. Slater’s Quantum Theory of Matter. In the present book the three authors, Michael Morrison, Thomas Estle and Neal Lane, stress the unity among these fields by ernphasizing the concept of electronic quantum states in atoms, diatomic molecules and crystalline solids. Such a combination should be of basic interest to students in a variety of scientific fields and also form the basis for more advanced work in those three subjects themselves. …
Comparison Of Experimental And Theoretical Electron Ejection Cross Sections In Helium By Proton Impact From 5 To 100 Kev, M. Eugene Rudd, D. H. Madison
Comparison Of Experimental And Theoretical Electron Ejection Cross Sections In Helium By Proton Impact From 5 To 100 Kev, M. Eugene Rudd, D. H. Madison
M. Eugene Rudd Publications
Absolute values of doubly differential cross sections are obtained for electron production in helium by 5- to 100-keV proton impact. The measured values along with earlier data at higher energies are compared with theoretical plane-wave Born-approximation functions obtained from a Hartree-Fock potential. Not only is good agreement obtained at high impact energies (above 300 keV), but fairly good agreement is found at low energies (below about 20 keV). For electrons ejected in the backward hemisphere, unexpectedly poor agreement is noted at intermediate energies where the measured cross sections dip to 50% of the calculated values in some cases. Singly differential …
Cross Sections For L2,3 Auger Emission In 22- To 300-Kev H+ + Ar Collisions, M. Eugene Rudd
Cross Sections For L2,3 Auger Emission In 22- To 300-Kev H+ + Ar Collisions, M. Eugene Rudd
M. Eugene Rudd Publications
Measurements of total and differential L2,3 Auger cross sections for H+ + Ar collisions at 22 - 150 keV are presented. Additional values of these cross sections were calculated from data in earlier investigations by Volz and Rudd and by Crooks and Rudd up to 300 keV. Angular distributions are found to be isotropic. Over most of the energy range the total Auger cross sections are a factor of 2 smaller than predicted by Garcia's binary-encounter calculations.
Production And Decay Of Double L Vacancies In Argon And Phosphorus, M. Eugene Rudd, B. Fastrup, P. Dahl, F. D. Schowengerdt
Production And Decay Of Double L Vacancies In Argon And Phosphorus, M. Eugene Rudd, B. Fastrup, P. Dahl, F. D. Schowengerdt
M. Eugene Rudd Publications
Measurements have been made at two laboratories which indicate that the structure reported at 450-550eV in the electron spectrum from Ar+-Ar collisions by Ogurtsov, Flaks, and Avakyan is spurious. It is argued that the double L vacancies which they invoke to explain the structure are more likely to decay by the two-step Auger process L 2→LM2→M4 than by the one-step process L2→M3 suggested by these authors. Evidence supporting this is found in our electron spectra from P+-Ar collisions, where it is known from energy-loss and charge-state measurements that double …
Autoionization Of He And Autodetachment Of He- Following Bombardment By H+, H2+, He+, And He Atoms, F. D. Schowengerdt, S. R. Smart, M. Eugene Rudd
Autoionization Of He And Autodetachment Of He- Following Bombardment By H+, H2+, He+, And He Atoms, F. D. Schowengerdt, S. R. Smart, M. Eugene Rudd
M. Eugene Rudd Publications
Presented here are experimental results of a study of the systematics of electron emission from discrete states of He and He- as produced by H+, H2+, He+, and He impacts. The results were obtained by energy analysis of the electrons emitted at angles of 10° to 160°. Projectile energies ranged from 20 to 150 keV. Differential and integrated cross sections are presented for emission of electrons from the 2s2 (1S), 2s2p(3P), the sum of the 2p2 (1D) and 2s2p(1P) autoionizing levels of He, …
Observation Of A Broad Resonance In The 23S Excitation Of Helium By Electron Impact, G. B. Crooks, R. D. Dubois, D. E. Golden, M. Eugene Rudd
Observation Of A Broad Resonance In The 23S Excitation Of Helium By Electron Impact, G. B. Crooks, R. D. Dubois, D. E. Golden, M. Eugene Rudd
M. Eugene Rudd Publications
We have observed a broad P-wave resonance at about 50 eV primary energy in the angular distribution of electrons scattered after excitation of the 23S state of helium. The resonance has a width of about 15 eV and affects the differential excitation cross section by more than 3 orders of magnitude. It is suggested that this resonance is associated with the temporary formation of triply excited states of the negative helium ion.
Strong, Quasiperiodic Dependence Of Autoionization Shape Parameters On Projectile Energy In H+ + He Collisions, F. D. Schowengerdt, M. Eugene Rudd
Strong, Quasiperiodic Dependence Of Autoionization Shape Parameters On Projectile Energy In H+ + He Collisions, F. D. Schowengerdt, M. Eugene Rudd
M. Eugene Rudd Publications
Profiles of the 2s2 (1S) autoionizing state in He have been observed in the ejected-electron spectrum of H+ + He for small angles of ejection and for H+ energies of 6 to 150 keV. The shape parameter q shows an increasing dependence on projectile energy as the angle of ejection is decreased, with strong, quasiperiodic oscillations appearing at 10°.
Angular And Energy Distribution Of Cross Sections For Electron Production By 50-300-Kev-Proton Impacts On N2, O2, Ne, And Ar, J. B. Crooks, M. Eugene Rudd
Angular And Energy Distribution Of Cross Sections For Electron Production By 50-300-Kev-Proton Impacts On N2, O2, Ne, And Ar, J. B. Crooks, M. Eugene Rudd
M. Eugene Rudd Publications
Cross sections differential in angle and ejection energy for electron production by proton impact on nitrogen, oxygen, neon, and argon have been measured using electrostatic analysis and counting of individual electrons. The range of proton energies was 50-300 keV, the angles ranged from 10° to 160°, and the electron energies were measured from 1.5 to 1057 eV. Integrations over angle and/or electron energy yielded singly differential and total electron production cross sections. Our total cross sections for oxygen fall halfway between previous data of deHeer et al. and Hooper et al., but our argon cross sections agree better with deHeer …
Comparison Of Experimental And Theoretical Values Of Cross Sections For Electron Production By Proton Impact, M. Eugene Rudd, D. Gregoire, J. B. Crooks
Comparison Of Experimental And Theoretical Values Of Cross Sections For Electron Production By Proton Impact, M. Eugene Rudd, D. Gregoire, J. B. Crooks
M. Eugene Rudd Publications
Angle and energy distributions of electrons ejected from single- and multishell atoms by 50-to 300-keV protons are compared with various theoretical treatments. Partial cross sections for each subshell are calculated by scaling according to the number of electrons and the binding energy and then are added. The Born approximation fails at large and at small angles but yields fair agreement at intermediate angles. The treatments of Salin and of Macek, which take account of the influence of the projectile after the collision, yield much improved agreement at small angles. The binary-encounter model is used to calculate cross sections which are …
Emission Of Auger Electrons Resulting From Symmetric Argon And Neon Ion-Atom Collisions, R. K. Cacak, Q. C. Kessel, M. Eugene Rudd
Emission Of Auger Electrons Resulting From Symmetric Argon And Neon Ion-Atom Collisions, R. K. Cacak, Q. C. Kessel, M. Eugene Rudd
M. Eugene Rudd Publications
Cross sections for the emission of Auger electrons from excited atoms and ions produced in symmetric Ar+-Ar and Ne+-Ne collisions have been measured at ion energies from 50 to 300 keV. A simple model is proposed to explain the dependence of the cross section on the impact energy; the predicted results agree well with the experiment. Also, the argon x-ray data of Saris and Onderdelinden are compared with the model and with the results of this experiment.
Auger Electrons From Argon With Energies 150-210 Ev Produced By H+ And H2 Impacts, D. J. Volz, M. Eugene Rudd
Auger Electrons From Argon With Energies 150-210 Ev Produced By H+ And H2 Impacts, D. J. Volz, M. Eugene Rudd
M. Eugene Rudd Publications
Secondary electrons in the energy range 150-210 eV produced by 125-300-keV H+ and H2+ impacts on argon gas are measured as a function of their energy and angle of emission. Discrete line spectra are due to Auger transitions from L2 and L3 vacancy states as well as satellite transitions from multivacancy states. The widths, energies, and branching ratios of the L2 and L3 vacancy states are presented. Widths of these states are appreciably greater than those obtained with electron impact excitation. This can be attributed to the recoil velocities of the target atom …
Experimental Evidence For The Mechanism Of Charge Transfer Into Continuum States, G. B. Crooks, M. Eugene Rudd
Experimental Evidence For The Mechanism Of Charge Transfer Into Continuum States, G. B. Crooks, M. Eugene Rudd
M. Eugene Rudd Publications
We have observed a prominent peak in the energy spectrum of electrons ejected in the forward direction from helium bombarded by protons ranging in energy from 100 to 300 keV. The peak occurs at an ejected-electron velocity equal to the velocity of the incident proton. The experimental results verify the existence of the mechanism of charge transfer into continuum states of the incident ion.