Excitation and ionisation cross-sections in condensed-phase biomaterials by electrons down to very low energy: application to liquid water and genetic building blocks

A model is presented for computing electron-impact electronic excitation and ionisation cross-sections for arbitrary condensed-phase biomaterials in a wide energy range, showing a general good agreement with the available experimental data.

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Spectroscopic information of 6Li from elastic scattering of deuterons, 3He and 4He by 6Li

International Journal of Modern Physics E ◽

10.1142/s0218301314500414 ◽

2014 ◽

Vol 23 (08) ◽

pp. 1450041

Author(s):

A. Amar

Keyword(s):

Elastic Scattering ◽

Cross Sections ◽

Optical Potential ◽

Wide Energy Range ◽

Spectroscopic Information ◽

Wide Energy ◽

Double Folding ◽

Potential Parameters ◽

Coupled Reaction ◽

Good Agreement

The elastic scattering of deuterons, 3 He and 4 He on 6 Li at different incident energies have been analyzed in the framework of the optical model (OM) using ECIS88 as well as SPI GENOA codes. The optical potential parameters were extracted in the phenomenological treatment. A good agreement between theoretical and experimental differential cross-sections was obtained in whole angular range. Parameters for real part of potential have been also calculated microscopically with double-folding model for the d, 3 He and 4 He scattering, respectively, using DFPOT code. The elastic transfer mechanism has been studied by coupled reaction channel (CRC) method using FRESCO code. Spectroscopic amplitudes of 6 Li ≡ t + 3 He and 6 Li ≡ α + d configurations have been extracted from d, 3 He and 4 He scattering on 6 Li at wide energy range. A comparison between spectroscopic amplitudes obtained from deuteron and α elastically scattering from 6 Li has been made. The extracted spectroscopic amplitudes of 6 Li ≡ 4 He + d( SF = SA 2) from 6 Li (d, 6 Li )d and 6 Li (α, 6 Li )α are not the same as expected theoretically.

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Fission probability in the 232Th(p,p′xnf) reaction at low energy

Canadian Journal of Chemistry ◽

10.1139/v83-118 ◽

1983 ◽

Vol 61 (4) ◽

pp. 646-648

Author(s):

Chien Chung ◽

James J. Hogan ◽

Hans H. Muleer

Keyword(s):

Experimental Data ◽

Cross Sections ◽

Low Energy ◽

Incident Proton ◽

Mass Ratio ◽

Dispersion Data ◽

Fission Probability ◽

Comparison Of The Results ◽

Good Agreement ◽

Model Approach

In our recent works, a model was developed to calculate many of the features of 232Th(p,X) reactions with incident proton energies to 100 MeV. The model reproduced many properties such as spallation excitation functions, total fission cross sections, the symmetric/asymmetric mass ratio, and fission charge dispersion data. In this work, the model approach is extended to consider the fission probability in 232Th(p,p′xnf) fission channels. A comparison of the results calculated from the model to the experimental data shows very good agreement, and again justifies the approach of the model.

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Cluster observation of few-hour-scale evolution of structured plasma in the inner magnetosphere

Annales Geophysicae ◽

10.5194/angeo-31-1569-2013 ◽

2013 ◽

Vol 31 (9) ◽

pp. 1569-1578 ◽

Cited By ~ 6

Author(s):

M. Yamauchi ◽

I. Dandouras ◽

H. Rème ◽

R. Lundin ◽

L. M. Kistler

Keyword(s):

Local Time ◽

Trapped Ions ◽

Low Energy ◽

Local Times ◽

Significant Enhancement ◽

Occurrence Rate ◽

Wide Energy Range ◽

Inner Magnetosphere ◽

Wide Energy ◽

Cluster Ion

Abstract. Using Cluster Ion Spectrometry (CIS) data from the spacecraft-4 perigee traversals during the 2001–2006 period (nearly 500 traversals after removing those that are highly contaminated by radiation belt particles), we statistically examined the local time distribution of structured trapped ions at sub- to few-keV range as well as inbound–outbound differences of these ion signatures in intensities and energy–latitude dispersion directions. Since the Cluster orbit during this period was almost constant and approximately north–south symmetric at nearly constant local time near the perigee, inbound–outbound differences are attributed to temporal developments in a 1–2 h timescale. Three types of structured ions at sub- to few keV range that are commonly found in the inner magnetosphere are examined: – Energy–latitude dispersed structured ions at less than a few keV, – Short-lived dispersionless ion stripes at wide energy range extending 0.1–10 keV, – Short-lived low-energy ion bursts at less than a few hundred eV. The statistics revealed that the wedge-like dispersed ions are most often observed in the dawn sector (60% of traversals), and a large portion of them show significant enhancement during the traversals at all local times. The short-lived ion stripes are predominantly found near midnight, where most stripes are significantly enhanced during the traversals and are associated with substorm activities with geomagnetic AL < −300 nT. The low-energy bursts are observed at all local times and under all geomagnetic conditions, with moderate peak of the occurrence rate in the afternoon sector. A large portion of them again show significant enhancement or decay during the traversals.

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Energy Dependence of Total Cross Sections for Reactions with 4, 6he, 6, 7, 9li Nuclei

KnE Energy ◽

10.18502/ken.v3i1.1717 ◽

2018 ◽

Vol 3 (1) ◽

pp. 21

Author(s):

Yu Penionzhkevich ◽

Yu Sobolev ◽

V Samarin ◽

M Naumenko

Keyword(s):

Experimental Data ◽

Energy Range ◽

Numerical Solution ◽

Energy Dependence ◽

Cross Sections ◽

Beam Energy ◽

Microscopic Analysis ◽

Time Dependent ◽

Total Cross Sections ◽

Good Agreement

The paper presents the results of measurement of the total cross sections for reactions 4,6He + Si and 6,7,9Li + Si in the beam energy range 5−50 A⋅MeV. The enhancements of the total cross sections for reaction 6He + Si compared with reaction 4He + Si, and 9Li + Si compared with reactions 6,7Li + Si have been observed. The performed microscopic analysis of total cross sections for reactions 6He + Si and 9Li + Si based on numerical solution of the time-dependent Schrödinger equation for external neutrons of projectile nuclei 6He and 9Li yielded good agreement with experimental data.

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RELATIVISTIC OPTICAL MODEL FOR PROTON-NUCLEUS ELASTIC SCATTERING

International Journal of Modern Physics E ◽

10.1142/s0218301302000983 ◽

2002 ◽

Vol 11 (05) ◽

pp. 425-436 ◽

Cited By ~ 1

Author(s):

M. Y. H. FARAG ◽

M. Y. M. HASSAN

Keyword(s):

Experimental Data ◽

Elastic Scattering ◽

Cross Sections ◽

Differential Cross ◽

Optical Potential ◽

Optical Model ◽

Potential Model ◽

Optical Potential Model ◽

Relativistic Description ◽

Good Agreement

The relativistic description of the proton-nucleus elastic scattering can be considered within the framework of a relativistic optical potential model. The elastic scattering of proton with the nuclei 12 C , 16 O , 20 Ne , and 24 Mg at 800 MeV and 1.04 GeV are studied for relativistic and nonrelativistic treatments. The real optical potentials and the differential cross sections of these reactions are calculated. The obtained results are compared with the corresponding results obtained from the calculation depending on the Woods–Saxon optical potential which were adjusted to fit the experimental data. The present results are in good agreement with the experimental data.

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Quest for precision in hadronic cross sections at low energy: Monte Carlo tools vs. experimental data

The European Physical Journal C ◽

10.1140/epjc/s10052-010-1251-4 ◽

2010 ◽

Vol 66 (3-4) ◽

pp. 585-686 ◽

Cited By ~ 200

Author(s):

S. Actis ◽

◽

A. Arbuzov ◽

G. Balossini ◽

P. Beltrame ◽

...

Keyword(s):

Experimental Data ◽

Monte Carlo ◽

Cross Sections ◽

Low Energy

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Microscopic spin-orbit potential for p +6He elastic scattering

International Journal of Modern Physics E ◽

10.1142/s0218301319500745 ◽

2019 ◽

Vol 28 (09) ◽

pp. 1950074

Author(s):

Zakaria M. M. Mahmoud ◽

Awad A. Ibraheem ◽

M. A. Hassanain

Keyword(s):

Experimental Data ◽

Elastic Scattering ◽

Cross Sections ◽

Optical Model ◽

Spin Orbit ◽

Current Form ◽

Density Distributions ◽

Orbit Potential ◽

Scattering Cross Sections ◽

Good Agreement

In this work, we simultaneously reanalyzed the differential elastic scattering cross-sections ([Formula: see text]) and the vector analyzing power ([Formula: see text]) of [Formula: see text]He elastic scattering. This analysis was performed using the folded optical model for both real central and spin-orbit (SO) potentials, respectively. For the imaginary central, we used the usual Woods-Saxon (WS) form. Three different model density distributions are used to calculate the potential. We aimed to examine the applicability of the microscopically derived SO potential and the structure effect of 6He nucleus. The presence of the [Formula: see text] experimental data of [Formula: see text]He makes it interesting for this study. Our calculations showed that the three densities gave similar predictions for the cross-sections data. The three microscopic SO potentials calculations of [Formula: see text] are not in a good agreement with the experimental data. We concluded that the SO formalism in its current form needs more investigations for exotic halo nuclei.

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K-, L-, and M-shell ionization of atoms by electron and positron impact

Canadian Journal of Physics ◽

10.1139/p96-055 ◽

1996 ◽

Vol 74 (7-8) ◽

pp. 376-383 ◽

Cited By ~ 44

Author(s):

S. P. Khare ◽

J. M. Wadehra

Keyword(s):

Experimental Data ◽

Cross Sections ◽

Positron Impact ◽

Electrons And Positrons ◽

Virtual Photons ◽

Plane Wave Born Approximation ◽

Ionization Cross Sections ◽

Impact Energies ◽

Shell Ionization ◽

Good Agreement

The plane-wave Born approximation with Coulomb, relativistic, and exchange corrections is employed to obtain the K-, L1-, L2-, L3-, and M-shell ionization cross sections of a number of atoms bombarded by electrons and positrons in the energy range varying from the threshold of ionization to 1 GeV. Transverse interaction of virtual photons with atoms is also included and it is found to be of great significance for impact energies greater than about 1 MeV. For K- and L-shell ionization, good agreement between the theoretical values and various experimental data for electron-impact cross sections is obtained. However, for the M shell, the theory overestimates the experimental cross sections. For positron impact the agreement between the present results and the limited experimental data is found to be quite satisfactory.

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Comparison of reaction theories for multilevel interference—the 14C + p reactions

Canadian Journal of Physics ◽

10.1139/p69-338 ◽

1969 ◽

Vol 47 (24) ◽

pp. 2763-2777 ◽

Cited By ~ 9

Author(s):

C. T. Tindle ◽

E. Vogt

Keyword(s):

Compound Nucleus ◽

Cross Sections ◽

Curve Fitting ◽

Low Energy ◽

Analytic Method ◽

R Matrix ◽

Strong Interference ◽

S Matrix ◽

Fitting Procedures ◽

Good Agreement

A comparison is made between the R-matrix and S-matrix theories of low-energy compound nucleus resonances for the particular case of two-level interference. The (p,γ) and (p,n) cross sections of 14C for proton energies between 0.7 and 1.5 MeV are analyzed using both theories. The 15N compound nucleus in this region exhibits strong two-level interference. The two theories provide equally good fits to the data, but the parameters describing the compound-nucleus levels are quite different. A general analytic method of relating the two sets of parameters is derived and shown to give good agreement with the results obtained by curve-fitting procedures. Remarks are made concerning the general behavior of the parameters under strong interference conditions and also on the inclusion of many channels into the analysis.

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