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Mahla S, Antony B. Positron scattering from structurally related biomolecules. RSC Adv 2024; 14:1397-1406. [PMID: 38174274 PMCID: PMC10763659 DOI: 10.1039/d3ra06227a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024] Open
Abstract
We report the integral elastic, momentum transfer, and inelastic (positronium formation and ionisation) cross sections for positron scattering from structurally related molecules. The molecules chosen for the current investigation are formamide, formylphosphine, formic acid, N-methylformamide, acetone, acetic acid, and formaldehyde. The cross sections were calculated using the optical potential approach and the complex scattering potential-ionisation contribution method for impact energies between 1 and 5 keV. A sizable repository of data is now available for positron scattering from various atoms and molecules; however, data on the impact of positrons on current targets is still scarce and fragmented. While most cross sections are the first of their kind, we analyze our total cross sections (TCSs) with the previous literature available, which has become attractive to researchers trying to model the tracks of charged particles in matter. TCSs have recently seen a resurgence in popularity thanks to their utility in specifying the mean-free path between the collisions of such simulations. We find good qualitative convergence between experimental and theoretical results below and above the positronium formation threshold. However, around the threshold region, a significant discrepancy is encountered, which can be accounted for due to the experiment's lack of forward angle scattering effect discrimination. This level of agreement evolves to become quantitative at intermediate and higher energies.
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Affiliation(s)
- Sapna Mahla
- Department of Physics, Indian Institute of Technology (ISM) Dhanbad JH 826004 India
| | - Bobby Antony
- Department of Physics, Indian Institute of Technology (ISM) Dhanbad JH 826004 India
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2
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Lozano AI, García-Abenza A, Blanco Ramos F, Hasan M, Slaughter DS, Weber T, McEachran RP, White RD, Brunger MJ, Limão-Vieira P, García Gómez-Tejedor G. Electron and Positron Scattering Cross Sections from CO 2: A Comparative Study over a Broad Energy Range (0.1-5000 eV). J Phys Chem A 2022; 126:6032-6046. [PMID: 36069053 PMCID: PMC9483986 DOI: 10.1021/acs.jpca.2c05005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/30/2022] [Indexed: 12/03/2022]
Abstract
In this Review, we present a comparative study between electron and positron scattering cross sections from CO2 molecules over a broad impact energy range (0.1-5000 eV). For electron scattering, new total electron scattering cross sections (e-TCS) have been measured with a high resolution magnetically confined electron beam transmission system from 1 to 200 eV. Dissociative electron attachment processes for electron energies from 3 to 52 eV have been analyzed by measuring the relative O- anion production yield. In addition, elastic, inelastic, and total scattering cross section calculations have been carried out in the framework of the Independent Atom Model by using the Screening Corrected Additive Rule, including interference effects (IAM-SCARI). Based on the previous cross section compilation from Itikawa ( J. Phys. Chem. Ref. Data, 2002, 31, 749-767) and the present measurements and calculations, an updated recommended e-TCS data set has been used as reference values to obtain a self-consistent integral cross section data set for the elastic and inelastic (vibrational excitation, electronic excitation, and ionization) scattering channels. A similar calculation has been carried out for positrons, which shows important differences between the electron scattering behavior: e.g., more relevance of the target polarization at the lower energies, more efficient excitation of the target at intermediate energies, but a lower total scattering cross section for increasing energies, even at 5000 eV. This result does not agree with the charge independence of the scattering cross section predicted by the first Born approximation (FBA). However, we have shown that the inelastic channels follow the FBA's predictions for energies above 500 eV while the elastic part, due to the different signs of the scattering potential constituent terms, remains lower for positrons even at the maximum impact energy considered here (5000 eV). As in the case of electrons, a self-consistent set of integral positron scattering cross sections, including elastic and inelastic (vibrational excitation, electronic excitation, positronium formation, and ionization) channels is provided. Again, to derive these data, positron scattering total cross sections based on a previous compilation from Brunger et al. ( J. Phys. Chem. Ref. Data, 2017, 46, 023102) and the present calculation have been used as reference values. Data for the main inelastic channels, i.e. direct ionization and positronium formation, derived with this procedure, show excellent agreement with the experimental results available in the literature. Inconsistencies found between different model potential calculations, both for the elastic and inelastic collision processes, suggest that new calculations using more sophisticated methods are required.
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Affiliation(s)
- Ana I. Lozano
- Instituto
de Física Fundamental, Consejo Superior
de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain
- Laboratório
de Colisões Atómicas e Moleculares, CEFITEC, Departamento
de Física, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Adrián García-Abenza
- Instituto
de Física Fundamental, Consejo Superior
de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain
| | - Francisco Blanco Ramos
- Departamento
de Estructura de la Materia, Física Térmica y Electrónica
e IPARCOS, Universidad Complutense de Madrid, Avenida Complutense, E-28040 Madrid, Spain
| | - Mahmudul Hasan
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Department
of Physics and Astronomy, University of
Nebraska−Lincoln, Lincoln, Nebraska 68588, United States
| | - Daniel S. Slaughter
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Thorsten Weber
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Robert P. McEachran
- The Research
School of Physics, Australian National University, Canberra, ACT 0200, Australia
| | - Ronald D. White
- College
of Science and Engineering, James Cook University, Townsville 4810, Australia
| | - Michael J. Brunger
- College
of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
- Department
of Actuarial Science and Applied Statistics, Faculty of Business and
Management, UCSI University, Kuala Lumpur 56000, Malaysia
| | - Paulo Limão-Vieira
- Laboratório
de Colisões Atómicas e Moleculares, CEFITEC, Departamento
de Física, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Gustavo García Gómez-Tejedor
- Instituto
de Física Fundamental, Consejo Superior
de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
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3
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Cheong Z, Moreira GM, Bettega MHF, Blanco F, Garcia G, Brunger MJ, White RD, Sullivan JP. A comparison of experimental and theoretical low energy positron scattering from furan. J Chem Phys 2020; 153:244303. [PMID: 33380099 DOI: 10.1063/5.0027874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
This paper presents a joint experimental and theoretical study of positron scattering from furan. Experimental data were measured using the low energy positron beamline located at the Australian National University and cover an energy range from 1 eV to 30 eV. Cross sections were measured for total scattering, total elastic and inelastic scattering, positronium formation, and differential elastic scattering. Two theoretical approaches are presented: the Schwinger multichannel method and the independent atom method with screening corrected additivity rule. In addition, our data are compared to corresponding electron scattering results from the same target with a number of significant differences observed and discussed.
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Affiliation(s)
- Z Cheong
- Laser Physics Centre, Research School of Physics, Australian National University, Canberra, Australia
| | - G M Moreira
- Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-980 Curitiba, Paraná, Brazil
| | - M H F Bettega
- Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-980 Curitiba, Paraná, Brazil
| | - F Blanco
- Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - G Garcia
- Instituto de Fısica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 113-bis, 28006 Madrid, Spain
| | - M J Brunger
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - R D White
- College of Science and Engineering, James Cook University, Townsville, Qld., Australia
| | - J P Sullivan
- Laser Physics Centre, Research School of Physics, Australian National University, Canberra, Australia
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4
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Abstract
A review on the positron scattering from atoms and molecules is presented in this article. The focus on positron scattering studies is on the rise due to their presence in various fields and application of cross section data in such environments. Positron scattering is usually investigated using theoretical approaches that are similar to those for electron scattering, being its anti-particle. However, most experimental or theoretical studies are limited to the investigation of electron and positron scattering from inert gases, single electron systems and simple or symmetric molecules. Optical potential and polarized orbital approaches are the widely used methods for investigating positron scattering from atoms. Close coupling approach has also been used for scattering from atoms, but for lighter targets with low energy projectiles. The theoretical approaches have been quite successful in predicting cross sections and agree reasonably well with experimental measurements. The comparison is generally good for electrons for both elastic and inelastic scatterings cross sections, while spin polarization has been critical due to its sensitive perturbing interaction. Positron scattering cross sections show relatively less features than that of electron scattering. The features of positron impact elastic scattering have been consistent with experiment, while total cross section requires significant improvement. For scattering from molecules, utilization of both spherical complex optical potential and R-matrix methods have proved to be efficient in predicting cross sections in their respective energy ranges. The results obtained shows reasonable comparison with most of the existing data, wherever available. In the present article we illustrate these findings with a list of comprehensive references to data sources, albeit not exhaustive.
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5
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Sinha N, Patel D, Antony B. Positron Scattering: Total Elastic and Grand Total Cross Sections for Molecules of Astrophysical Importance. ChemistrySelect 2019. [DOI: 10.1002/slct.201803338] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Nidhi Sinha
- Department of PhysicsIndian Institution of Technology (Indian School of Mines) Dhanbad Jharkhand-826004 India
| | - Durgesini Patel
- Department of PhysicsIndian Institution of Technology (Indian School of Mines) Dhanbad Jharkhand-826004 India
| | - Bobby Antony
- Department of PhysicsIndian Institution of Technology (Indian School of Mines) Dhanbad Jharkhand-826004 India
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6
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Lozano AI, Oller JC, Krupa K, Ferreira da Silva F, Limão-Vieira P, Blanco F, Muñoz A, Colmenares R, García G. Magnetically confined electron beam system for high resolution electron transmission-beam experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:063105. [PMID: 29960528 DOI: 10.1063/1.5030068] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A novel experimental setup has been implemented to provide accurate electron scattering cross sections from molecules at low and intermediate impact energies (1-300 eV) by measuring the attenuation of a magnetically confined linear electron beam from a molecular target. High-resolution electron energy is achieved through confinement in a magnetic gas trap where electrons are cooled by successive collisions with N2. Additionally, we developed and present a method to correct systematic errors arising from energy and angular resolution limitations. The accuracy of the entire measurement procedure is validated by comparing the N2 total scattering cross section in the considered energy range with benchmark values available in the literature.
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Affiliation(s)
- A I Lozano
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - J C Oller
- Centro de Investigaciones Energéticas Medioambientales y Tecnológicas, Madrid, Spain
| | - K Krupa
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - F Ferreira da Silva
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - P Limão-Vieira
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - F Blanco
- Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid, Spain
| | - A Muñoz
- Centro de Investigaciones Energéticas Medioambientales y Tecnológicas, Madrid, Spain
| | - R Colmenares
- Servicio de Radiofísica, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - G García
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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7
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Stevens D, Babij TJ, Machacek JR, Buckman SJ, Brunger MJ, White RD, García G, Blanco F, Ellis-Gibbings L, Sullivan JP. Positron scattering from pyridine. J Chem Phys 2018; 148:144308. [DOI: 10.1063/1.5024246] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- D. Stevens
- Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Acton, Canberra 2601, Australia
| | - T. J. Babij
- Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Acton, Canberra 2601, Australia
| | - J. R. Machacek
- Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Acton, Canberra 2601, Australia
| | - S. J. Buckman
- Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Acton, Canberra 2601, Australia
| | - M. J. Brunger
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - R. D. White
- College of Science and Engineering, James Cook University, Townsville, Qld., Australia
| | - G. García
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain
| | - F. Blanco
- Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - L. Ellis-Gibbings
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain
| | - J. P. Sullivan
- Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Acton, Canberra 2601, Australia
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8
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Loreti A, Kadokura R, Fayer SE, Kövér Á, Laricchia G. High-Resolution Measurements of e^{+}+H_{2}O Total Cross Section. PHYSICAL REVIEW LETTERS 2016; 117:253401. [PMID: 28036208 DOI: 10.1103/physrevlett.117.253401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Indexed: 06/06/2023]
Abstract
Using a purely electrostatic positron beam, the total cross section of positrons scattering from H_{2}O has been measured for the first time with a high angular discrimination (≃1°) against forward scattered projectiles. Results are presented in the energy range (10-300) eV. Significant deviations from previous measurements are found which are, if ascribed entirely to the angular acceptances of various experimental systems, in quantitative accord with ab initio theoretical predictions of the differential elastic scattering cross section.
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Affiliation(s)
- A Loreti
- UCL Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - R Kadokura
- UCL Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - S E Fayer
- UCL Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Á Kövér
- Institute for Nuclear Research of Hungarian Academy of Science, Debrecen, PO Box 51, H-4001, Hungary
| | - G Laricchia
- UCL Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
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9
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Chiari L, Zecca A, Blanco F, García G, Brunger MJ. Experimental and theoretical cross sections for positron scattering from the pentane isomers. J Chem Phys 2016; 144:084301. [PMID: 26931696 DOI: 10.1063/1.4942472] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Isomerism is ubiquitous in chemistry, physics, and biology. In atomic and molecular physics, in particular, isomer effects are well known in electron-impact phenomena; however, very little is known for positron collisions. Here we report on a set of experimental and theoretical cross sections for low-energy positron scattering from the three structural isomers of pentane: normal-pentane, isopentane, and neopentane. Total cross sections for positron scattering from normal-pentane and isopentane were measured at the University of Trento at incident energies between 0.1 and 50 eV. Calculations of the total cross sections, integral cross sections for elastic scattering, positronium formation, and electronic excitations plus direct ionization, as well as elastic differential cross sections were computed for all three isomers between 1 and 1000 eV using the independent atom model with screening corrected additivity rule. No definitive evidence of a significant isomer effect in positron scattering from the pentane isomers appears to be present.
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Affiliation(s)
- L Chiari
- Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - A Zecca
- Department of Physics, University of Trento, Via Sommarive 14, Povo, Trento 38123, Italy
| | - F Blanco
- Departamento de Física Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - G García
- Instituto de Física Fundamental, Consejo Superior de Investigationes Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain
| | - M J Brunger
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
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10
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Abstract
The kinetic theory of non-relativistic positrons in an idealized positron emission tomography PET environment is developed by solving the Boltzmann equation, allowing for coherent and incoherent elastic, inelastic, ionizing and annihilating collisions through positronium formation. An analytic expression is obtained for the positronium formation rate, as a function of distance from a spherical source, in terms of the solutions of the general kinetic eigenvalue problem. Numerical estimates of the positron range - a fundamental limitation on the accuracy of PET, are given for positrons in a model of liquid water, a surrogate for human tissue. Comparisons are made with the ‘gas-phase’ assumption used in current models in which coherent scattering is suppressed. Our results show that this assumption leads to an error of the order of a factor of approximately 2, emphasizing the need to accurately account for the structure of the medium in PET simulations.
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11
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Anderson EK, Boadle RA, Machacek JR, Chiari L, Makochekanwa C, Buckman SJ, Brunger MJ, Garcia G, Blanco F, Ingolfsson O, Sullivan JP. Low energy positron interactions with uracil--total scattering, positronium formation, and differential elastic scattering cross sections. J Chem Phys 2014; 141:034306. [PMID: 25053319 DOI: 10.1063/1.4887072] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Measurements of the grand total and total positronium formation cross sections for positron scattering from uracil have been performed for energies between 1 and 180 eV, using a trap-based beam apparatus. Angular, quasi-elastic differential cross section measurements at 1, 3, 5, 10, and 20 eV are also presented and discussed. These measurements are compared to existing experimental results and theoretical calculations, including our own calculations using a variant of the independent atom approach.
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Affiliation(s)
- E K Anderson
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - R A Boadle
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - J R Machacek
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - L Chiari
- ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA, Australia
| | - C Makochekanwa
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - S J Buckman
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - M J Brunger
- ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA, Australia
| | - G Garcia
- Instituto de Fısica Fundamental, Consejo Superior de Investigationes Cientıficas (CSIC), Serrano 113-bis, E-28006 Madrid, Spain
| | - F Blanco
- Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - O Ingolfsson
- Department of Chemistry, Science Institute, University of Iceland, Reykjavík 107, Iceland
| | - J P Sullivan
- ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
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12
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Chiari L, Zecca A, Blanco F, García G, Perkins MV, Buckman SJ, Brunger MJ. Cross Sections for Positron Impact with 2,2,4-Trimethylpentane. J Phys Chem A 2014; 118:6466-72. [DOI: 10.1021/jp502632m] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Luca Chiari
- ARC
Centre of Excellence for Antimatter−Matter Studies, School
of Chemical and Physical Sciences, Flinders University, Adelaide, SA 5001, Australia
| | - Antonio Zecca
- Department
of Physics, University of Trento, Via Sommarive 14, I-38123 Povo, Trento, Italy
| | - Francisco Blanco
- Departamento
de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - Gustavo García
- Instituto de Física Fundamental, Consejo Superior
de Investigationes Científicas (CSIC), Serrano 113-bis, E-28006 Madrid, Spain
| | - Michael V. Perkins
- School
of Chemical and Physical Sciences, Flinders University, Adelaide, SA 5001, Australia
| | - Stephen J. Buckman
- ARC
Centre of Excellence for Antimatter−Matter Studies, Research
School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia
- Institute
of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Michael J. Brunger
- ARC
Centre of Excellence for Antimatter−Matter Studies, School
of Chemical and Physical Sciences, Flinders University, Adelaide, SA 5001, Australia
- Institute
of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
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