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Full-Text Articles in Physics
A Dynamical (E,2e) Investigation Into The Ionization Of The Outermost Orbitals Of R-Carvone, D. B. Jones, E. Ali, C. G. Ning, F. Ferreira Da Silva, O. Ingolfsson, M. C. A. Lopes, H. S. Chakraborty, Don H. Madison, M. J. Brunger
A Dynamical (E,2e) Investigation Into The Ionization Of The Outermost Orbitals Of R-Carvone, D. B. Jones, E. Ali, C. G. Ning, F. Ferreira Da Silva, O. Ingolfsson, M. C. A. Lopes, H. S. Chakraborty, Don H. Madison, M. J. Brunger
Physics Faculty Research & Creative Works
We report an experimental and theoretical investigation into the dynamics of electron-impact ionization of R-carvone. Experimental triple differential cross sections are obtained in asymmetric coplanar kinematic conditions for the ionization of the unresolved combination of the three outermost molecular orbitals (41a-39a) of R-carvone. These cross sections are compared with theoretical cross sections calculated within a molecular 3-body distorted wave (M3DW) framework employing either a proper orientation average or orbital average to account for the random orientation of the molecule probed in the experiment. Here, we observe that the overall scattering behavior observed in the experiment is fairly well reproduced within …
Multicenter Distorted-Wave Approach For Electron-Impact Ionization Of Molecules, Esam Ali, Don H. Madison
Multicenter Distorted-Wave Approach For Electron-Impact Ionization Of Molecules, Esam Ali, Don H. Madison
Physics Faculty Research & Creative Works
We have previously used the molecular three-body distorted-wave model to examine electron-impact single ionization of molecules. One of the possible weaknesses of this approach lies in the fact that the continuum electron wave functions do not depend on the orientation of the molecule. Here we introduce a model called the multicenter molecular three-body distorted-wave (MCM3DW) approach, for which the continuum electron wave functions depend on the orientation of the molecule at the time of ionization. The MCM3DW results are compared with experimental data taken from work by Dorn and colleagues [Ren, Phys. Rev. A 91, 032707 (2015)10.1103/PhysRevA.91.032707; Phys. Rev. A …
Natural & Unnatural-Parity Contributions In Electron-Impact Ionization Of Laser-Aligned Atoms, Andrew James Murray, James Colgan, Don H. Madison, Matthew Harvey, Ahmad Sakaamini, James Pursehouse, Kate Nixon, Al Stauffer
Natural & Unnatural-Parity Contributions In Electron-Impact Ionization Of Laser-Aligned Atoms, Andrew James Murray, James Colgan, Don H. Madison, Matthew Harvey, Ahmad Sakaamini, James Pursehouse, Kate Nixon, Al Stauffer
Physics Faculty Research & Creative Works
Differential cross section measurements from laser-aligned Mg atoms are compared to theoretical calculations using both time dependent and time-independent formalisms. It is found that both natural and unnatural parity contributions to the calculated cross sections are required to emulate the data when the state is aligned out of the scattering plane.
Electron-Impact Ionization Of H₂O At Low Projectile Energy: Internormalized Triple-Differential Cross Sections In Three-Dimensional Kinematics, Xueguang Ren, Sadek Amami, Khokon Hossen, Esam Ali, Chuangang Ning, James Colgan, Don H. Madison, Andrew Dorn
Electron-Impact Ionization Of H₂O At Low Projectile Energy: Internormalized Triple-Differential Cross Sections In Three-Dimensional Kinematics, Xueguang Ren, Sadek Amami, Khokon Hossen, Esam Ali, Chuangang Ning, James Colgan, Don H. Madison, Andrew Dorn
Physics Faculty Research & Creative Works
We report a combined experimental and theoretical study of the electron-impact ionization of water (H2O) at the relatively low incident energy of E0=81eV in which either the 1b1 or 3a1 orbitals are ionized leading to the stable H2O cation. The experimental data were measured by using a reaction microscope, which can cover nearly the entire 4π solid angle for the secondary electron emission over a range of ejection energies. We present experimental data for the scattering angles of 6⁰ and 10⁰ for the faster of the two outgoing electrons as a function …
Low-Energy (E₀ = 65 Ev) Electron-Impact Ionization Of Neon: Internormalized Triple-Differentical Cross Sections In 3d Kinematics, Xueguang Ren, Sadek M. Amami, Oleg I. Zatsarinny, Thomas Pfluger, Marvin Weyland, Woon Yong Baek, Hans Rabus, Klaus Bartschat, Don H. Madison, Alexander Dorn
Low-Energy (E₀ = 65 Ev) Electron-Impact Ionization Of Neon: Internormalized Triple-Differentical Cross Sections In 3d Kinematics, Xueguang Ren, Sadek M. Amami, Oleg I. Zatsarinny, Thomas Pfluger, Marvin Weyland, Woon Yong Baek, Hans Rabus, Klaus Bartschat, Don H. Madison, Alexander Dorn
Physics Faculty Research & Creative Works
We present a combined experimental and theoretical study on the low-energy (E0 = 65 eV) electron- impact ionization of neon. The experimental data are compared to predictions from a hybrid second-order distorted-wave Born plus R-matrix approach (DWB2-RM), the distorted-wave Born approximation with inclusion of post-collision interaction (DWBA-PCI), a three-body distorted-wave approach (3DW), and a B-spline R-matrix (BSR) with pseudostates approach. Excellent agreement is found between experiment and the 3DW and BSR theories. The importance of PCI effects is clearly visible in this low-energy electron-impact ionization process.
First Evidence Of Interference Effects In The Ionization Of N₂ Molecule, Zehra Nur Ozer, Hari Chaluvadi, Mevlut Dogan, James Colgan, Don H. Madison
First Evidence Of Interference Effects In The Ionization Of N₂ Molecule, Zehra Nur Ozer, Hari Chaluvadi, Mevlut Dogan, James Colgan, Don H. Madison
Physics Faculty Research & Creative Works
We will present an experimental and theoretical investigation of triple differential cross sections for electron- impact ionization of nitrogen molecules at intermediate energies. A discussion of interference effects contained in the theoretical and experimental interference factors will be presented.
Theoretical And Experimental Study Of (E,2e) Ionization Of The Co₂ (1ΠG) Molecule At 250 Ev, Mevlut Dogan, Zehra Nur Ozer, Murat Yavuz, Osman Alwan, Adnan Naja, Boghos B. Joulakian, Esam S M Ali, Chuangang Ning, Don H. Madison
Theoretical And Experimental Study Of (E,2e) Ionization Of The Co₂ (1ΠG) Molecule At 250 Ev, Mevlut Dogan, Zehra Nur Ozer, Murat Yavuz, Osman Alwan, Adnan Naja, Boghos B. Joulakian, Esam S M Ali, Chuangang Ning, Don H. Madison
Physics Faculty Research & Creative Works
Triple differential cross sections (TDCSs) of the electron-impact ionization of carbon dioxide are measured in the coplanar asymmetric geometry, with incident electron energy value of 250eV, and ejected electron of 37eV. We will report the experimental results in comparison with the theoretical calculations of the M3DW and TCC (type 5) calculations.
Coplanar Asymmetric Angles And Symmetric Energy Sharing Triple Differential Cross Sections For 200 Ev Electron-Impact Ionization Of Ar (3p), Zehra Nur Ozer, Sadek M. Amami, Onur Varol, Murat Yavuz, Mevlut Dogan, Don H. Madison
Coplanar Asymmetric Angles And Symmetric Energy Sharing Triple Differential Cross Sections For 200 Ev Electron-Impact Ionization Of Ar (3p), Zehra Nur Ozer, Sadek M. Amami, Onur Varol, Murat Yavuz, Mevlut Dogan, Don H. Madison
Physics Faculty Research & Creative Works
We have measured triple differential cross sections (TDCSs) for electron-impact ionization of the 3p shell of Ar at 200 eV incident electron energy. The experiments have been performed in coplanar asymmetric energy sharing geometry. The experimental results are compared with the theoretical models of three body distorted wave (3DW) and distorted wave Born approximation (DWBA).
Dynamical (E,2e) Investigations Of Structurally Related Cyclic Ethers, J. D. Builth-Williams, Luca Chiari, Penny A. Thorn, Susan M. Bellm, D. B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Oddur Ingólfsson, Michael J. Brunger
Dynamical (E,2e) Investigations Of Structurally Related Cyclic Ethers, J. D. Builth-Williams, Luca Chiari, Penny A. Thorn, Susan M. Bellm, D. B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Oddur Ingólfsson, Michael J. Brunger
Physics Faculty Research & Creative Works
Experimental and theoretical cross sections are presented for electron-impact ionization of a series of cyclic ethers.
Comparison Of Experiment And Theory For Electron Impact Ionization Of Isoelectronic Atoms And Molecules, Hari Chaluvadi, Kate L. Nixon, Sadek M. Amami, Andrew James Murray, Don H. Madison
Comparison Of Experiment And Theory For Electron Impact Ionization Of Isoelectronic Atoms And Molecules, Hari Chaluvadi, Kate L. Nixon, Sadek M. Amami, Andrew James Murray, Don H. Madison
Physics Faculty Research & Creative Works
Experimental and Theoretical Triply Differential Cross sections will be presented for low energy electron impact ionization of Ne, CH4, and NH3. The collision mechanisms responsible for the various structures found in the cross sections will be discussed.
Experimental And Theoretical Investigation Of The Triple Differential Cross Section For Electron Impact Ionization Of Pyrimidine Molecules, J. D. Builth-Williams, Susan M. Bellm, Darryl B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Michael J. Brunger
Experimental And Theoretical Investigation Of The Triple Differential Cross Section For Electron Impact Ionization Of Pyrimidine Molecules, J. D. Builth-Williams, Susan M. Bellm, Darryl B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Michael J. Brunger
Physics Faculty Research & Creative Works
Cross-section data for electron impact induced ionization of bio-molecules are important for modelling the deposition of energy within a biological medium and for gaining knowledge of electron driven processes at the molecular level. Triply differential cross sections have been measured for the electron impact ionization of the outer valence 7b 2 and 10a 1 orbitals of pyrimidine, using the (e, 2e) technique. The measurements have been performed with coplanar asymmetric kinematics, at an incident electron energy of 250 eV and ejected electron energy of 20 eV, for scattered electron angles of -5°, -10°, and -15°. The ejected electron angular range …
Low Energy (E,2e) Studies From Ch₄: Results From Symmetric Coplanar Experiments And Molecular Three-Body Distorted Wave Theory, Kate L. Nixon, Andrew James Murray, Hari Chaluvadi, Chuangang Ning, Don H. Madison
Low Energy (E,2e) Studies From Ch₄: Results From Symmetric Coplanar Experiments And Molecular Three-Body Distorted Wave Theory, Kate L. Nixon, Andrew James Murray, Hari Chaluvadi, Chuangang Ning, Don H. Madison
Physics Faculty Research & Creative Works
Low energy experimental and theoretical triply differential cross sections are presented for electron impact ionization of methane (CH4) for both the highest occupied molecular orbital (HOMO) and next highest occupied molecular orbital (NHOMO). The HOMO is a predominantly p-type orbital which is labeled 1t2 and the NHOMO is predominantly s-type labeled 2a 1. Coplanar symmetric (symmetric both in final state electron energies and observation angles) are presented for final state electron energies ranging from 2.5 to 20 eV. The theoretical M3DW (molecular three-body distorted wave) results are in surprisingly good agreement with experiment for the HOMO …
Dynamical (E, 2e) Studies Using Tetrahydrofuran As A Dna Analogue, Christopher J. Colyer, Susan M. Bellm, G. Friedrich Hanne, Ola A. Al-Hagan, Don H. Madison, Chuangang Ning, B. Lohmann
Dynamical (E, 2e) Studies Using Tetrahydrofuran As A Dna Analogue, Christopher J. Colyer, Susan M. Bellm, G. Friedrich Hanne, Ola A. Al-Hagan, Don H. Madison, Chuangang Ning, B. Lohmann
Physics Faculty Research & Creative Works
We present dynamical (e, 2e) measurements for the electron impact ionization of formic acid and tetrahydrofuran molecules performed under similar kinematics. The experiments have been performed in the coplanar asymmetric geometry for a range of momentum transfers, at an incident electron energy of 250 eV and with an ejected electron energy of 10eV. The experimental results are compared with theoretical calculations carried out using the molecular 3-body distorted wave (M3DW) model.
Recent Theoretical Progress In Treating Electron Impact Ionization Of Molecules, Ola A. Al-Hagan, Chuangang Ning, Kate L. Nixon, Andrew James Murray, Christopher J. Colyer, Mark A. Stevenson, B. Lohmann, Don H. Madison
Recent Theoretical Progress In Treating Electron Impact Ionization Of Molecules, Ola A. Al-Hagan, Chuangang Ning, Kate L. Nixon, Andrew James Murray, Christopher J. Colyer, Mark A. Stevenson, B. Lohmann, Don H. Madison
Physics Faculty Research & Creative Works
(e,2e) ionization differential cross sections are presented for several molecules. We will compare experimental results with theoretical calculations using the molecular three body distorted wave (M3DW) approximations for H 2, N2, H2O and Formic Acid (FA) using better wave-function for the molecules than we had in previous works. Generally, good agreement is found between the M3DW approach and experiments.
(E,2e) Study Of Two-Center Interference Effects In The Ionization Of N₂, Leigh R. Hargreaves, Christopher J. Colyer, Mark A. Stevenson, B. Lohmann, Ola A. Al-Hagan, Don H. Madison, Chuangang Ning
(E,2e) Study Of Two-Center Interference Effects In The Ionization Of N₂, Leigh R. Hargreaves, Christopher J. Colyer, Mark A. Stevenson, B. Lohmann, Ola A. Al-Hagan, Don H. Madison, Chuangang Ning
Physics Faculty Research & Creative Works
A number of previous studies have suggested the possibility of two-center interference effects in the single ionization of diatomic molecules such as H2 and N2. While interference effects have been successfully observed in the ionization of H2, to date evidence for interference in N2 ionization has yet to be conclusively demonstrated. This study presents triply differential cross sections for electron impact ionization of N2, measured using the (e,2e) technique. The data are probed for signatures of two-center interference effects. Evidence for interference manifesting in the cross sections is observed.