scholarly journals Cross-section measurements and production of 72Se with medium to high energy protons using arsenic containing targets

2019 ◽  
Vol 107 (4) ◽  
pp. 279-287 ◽  
Author(s):  
Anthony J. DeGraffenreid ◽  
Dmitri G. Medvedev ◽  
Timothy E. Phelps ◽  
Matthew D. Gott ◽  
Suzanne V. Smith ◽  
...  
Keyword(s):  
Gallium Arsenide ◽  
Energy Range ◽  
Cross Section ◽  
Incident Energy ◽  
Beam Current ◽  
High Energy ◽  
Excitation Functions ◽  
Maximum Cross Section ◽  
Positron Emitter ◽  
Parent Radionuclide

Abstract Experiments were performed to evaluate production of 72Se, parent radionuclide of the positron emitter 72As, at high energy at the Brookhaven Linac Isotope Producer (BLIP). Excitation functions for 75As(p, xn)72/75Se in the 52-105 MeV energy range were measured by irradiating thin gallium arsenide (GaAs) wafers. Maximum cross section value for the natAs(p, 4n)72Se reaction in the energy range was 103±9 mb at 52±1 MeV. Production size GaAs and arsenic metal (As°) targets were irradiated with 136 μA and 165 μA beam current possessing an initial Linac energy of 117 MeV. A total of 3.77±0.1 GBq (102±3 mCi) of 72Se was produced from a GaAs target at a calculated target entrance energy of 105.4 MeV, and 13.8±0.3 GBq (373±8 mCi) of 72Se from an As° target at a calculated incident energy of 49.5 MeV irradiated for 116.5 h and 68.9 h, respectively.

High-Energy Levels in 13N

1973 ◽  
Vol 51 (11) ◽  
pp. 1227-1237 ◽  
Author(s):  
D. F. Measday ◽  
M. Hasinoff ◽  
D. L. Johnson
Keyword(s):  
Inelastic Scattering ◽  
Energy Range ◽  
Energy Levels ◽  
High Energy ◽  
Beam Direction ◽  
Excitation Functions ◽  
Carbon Target ◽  
Γ Rays ◽  
Natural Carbon

A natural carbon target was bombarded by protons in the energy range Ep = 9 to 24 MeV (Ex = 10 to 24 MeV in 13N). High-energy γ rays were detected in a NaI crystal oriented at 90° to the beam direction. Excitation functions were obtained for the 12.71 and 15.11 MeV γ rays from inelastic scattering on 12C and for capture γ rays from the reaction 12C(p, γo)13N. New structure is reported for all these reactions.

Dissociative excitation of CF4 by controlled electron impact

1989 ◽  
Vol 67 (7) ◽  
pp. 699-705 ◽  
Author(s):  
S. Wang ◽  
J. L. Forand ◽  
J. W. McConkey
Keyword(s):  
Energy Range ◽  
Emission Spectrum ◽  
Electron Impact ◽  
Cross Sections ◽  
Incident Energy ◽  
Dissociative Excitation ◽  
Excitation Mechanism ◽  
Excitation Functions ◽  
Single Collision

Dissociative excitation of CF4 by electron impact has been studied under single-collision conditions for incident energies up to 600 eV. The emission spectrum in the range 50–130 nm shows many features arising from neutral and singly ionized fluorine and carbon fragments. Absolute cross sections for the observed features were measured at 200 eV incident energy, while the excitation functions of the most intense emissions were studied over the whole energy range. Cascade was shown to be the dominant excitation mechanism for some of these features.

Coherent analysis of 16O + 28Si excitation functions

1985 ◽  
Vol 63 (10) ◽  
pp. 1274-1277
Author(s):  
R. J. W. Hodgson
Keyword(s):  
Energy Range ◽  
Excitation Function ◽  
Energy Dependence ◽  
Cross Section ◽  
Elastic Cross Section ◽  
Excitation Functions ◽  
Extreme Sensitivity ◽  
The Cross

A prescription for separating the elastic cross section into its coherent and incoherent parts is used to gain more information about the excitation function at 90° and at 180°. Approximations become useless over most of the energy range owing to the extreme sensitivity of the cross section. Despite the apparent smooth energy dependence of the coherent and incoherent parts, interpolation does not generate the observed structure in the excitation functions.

scholarly journals Calculation of athermal recombination corrected dpa cross sections for proton, deuteron and heavy-ion irradiations using the PHITS code

2020 ◽  
Vol 239 ◽  
pp. 20011
Author(s):  
Yosuke Iwamoto ◽  
Shin-ichiro Meigo
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Damage Model ◽  
Incident Beam ◽  
Heavy Ion ◽  
High Energy ◽  
Defect Production ◽  
Deuteron Irradiation ◽  
Aluminium Copper

To provide the athermal recombination corrected dpa (arc-dpa) cross sections for proton, deuteron and heavy ion irradiations in the energy range from 1 MeV/u to 3 GeV/u., the defect production efficiencies for aluminium, copper and tungsten were implemented in the radiation damage model in PHITS. In general, the dpa cross section is large with increasing the number of protons of incident particle. For high-energy (around 1 GeV/u) proton and deuteron irradiation, the dpa cross section is close to that under 12C irradiation due to secondaries produced by the nuclear reaction. The ratio of arc-dpa cross section to the conventional Norgett-Robinson-Torrens dpa (NRT-dpa) cross section is around 0.2 with incident energies over 100 MeV for proton and deuteron irradiations. For the case of 12C and 48Ca, this ratio is ranged from 0.3 to 0.4 for incident beam energies below 3 GeV/u.

Ionization by protons in the energy range 100 to 450 keV

1963 ◽  
Vol 274 (1358) ◽  
pp. 365-370 ◽  
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Ionization Cross Section ◽  
Axial Magnetic Field ◽  
High Energy ◽  
Ionization Cross ◽  
Total Ionization ◽  
Ion Production ◽  
Ionization Cross Sections

Ionization by protons in the energy range 100 to 450 keV has been investigated by means of the well-known parallel-plate condenser method. A uniform axial magnetic field enables slow ion collection to be carried out over a precisely determined path length at pressures low enough to ensure single collision conditions. The total cross-section for slow ion production cr+, and the total ionization cross-section have been determined for protons in hydrogen, helium , neon, argon and krypton. It is found that charge transfer is very small above about 200 keV so that cr+ ~ cr e . The ionization cross-section for all cases falls off as E -1 log E where E is the energy of relative motion. At the high-energy limit of the present measurements, the proton ionization cross-sections agree closely with electron ionization cross-sections for the same relative velocity of impact. The results are therefore in agreement with the general predictions of the Born approximation.

scholarly journals Measurements of the 33S (n, α)30Si cross-section at n_TOF and ILL: Implications in neutron capture therapy

2020 ◽  
Vol 239 ◽  
pp. 01020
Author(s):  
Javier Praena ◽  
Isabelópez-Casas L ◽  
Mariaé-Gilarte Sabat ◽  
Fernando de Saavedra Arias ◽  
Ignacio Porras
Keyword(s):  
Solar System ◽  
Energy Range ◽  
Dose Rate ◽  
Cross Section ◽  
Neutron Capture ◽  
High Energy ◽  
Neutron Capture Therapy ◽  
Cross Section Data ◽  
Section Data ◽  
Significant Resonance

Up to a couple of years ago, the 33S(n, α)30Si cross-section data had been limited and scarce. The origin in the solar system of 36S had been the only motivation to study that cross-section. However, a few years ago, the 33S(n, α)30Si reaction was proposed as a possible target in neutron capture therapy (NCT) due to the excellent bio-properties of 33S and the significant resonance at 13.45 keV of the cross-section for which a high-energy α is emitted. Prior to the experiments carried out at n_TOF-CERN and at the Institut Laue-Langevin (ILL) facilities, the data situation was: no data from the thermal point up to 10 keV; from 10 keV to 300 keV, there was only one (n, α) measurement able to resolve the resonances with a questionable value of the 13.45-keV resonance; and the thermal point did not have a consistent value. Here we summarize three experiments that have been performed covering the whole energy range of interest in NCT and astrophysics. These experiments have solved the most important issues. The data of the present work and the evaluated data are used to calculate the dose rate in the tissue.

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