Alternative sources of neutron production other than nuclear fission reactions are important priorities in medical and nuclear applications due to costs, safety and ease of operation. In this work,
...12
C
and
13
C
thick targets for neutron production through
12
C(d,n)
13
N
and
13
C(d,n)
14
N
, respectively, have been manufactured and characterized by different techniques. In order to evaluate the irradiation effects on these materials, the targets were irradiated with 150 keV proton beam. A complete characterization of these samples was performed using scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Auger electron spectroscopy, X-ray photoemission spectroscopy and Raman spectroscopy. The results of these studies allowed us to establish that even though the irradiated samples present microstructural and chemical structure changes on its surface, the
12
C
and
13
C
thick targets were stable and would maintain their performance after proton irradiation at a fluence of
2.0
×
10
18
ions/cm
2
and
3.7
×
10
18
ions/cm
2
, respectively.
Graphical abstract
The aim of this study was to evaluate the induction and rejoining of DNA double strand breaks (DSBs) in melanoma cells exposed to low and high linear energy transfer (LET) radiation.
DSBs and ...survival were determined as a function of dose in melanoma cells (B16-F0) irradiated with monoenergetic proton and lithium beams and with a gamma source. Survival curves were obtained by clonogenic assay and fitted to the linear-quadratic model. DSBs were evaluated by the detection of phosphorylated histone H2AX (gammaH2AX) foci at 30 min and 6 h post-irradiation.
Survival curves showed the increasing effectiveness of radiation as a function of LET. gammaH2AX labeling showed an increase in the number of foci vs. dose for all the radiations evaluated. A decrease in the number of foci was found at 6 h post-irradiation for low LET radiation, revealing the repair capacity of DSBs. An increase in the size of gammaH2AX foci in cells irradiated with lithium beams was found, as compared with gamma and proton irradiations, which could be attributed to the clusters of DSBs induced by high LET radiation. Foci size increased at 6 h post-irradiation for lithium and proton irradiations in relation with persistent DSBs, showing a correlation with surviving fraction.
Our results showed the response of B16-F0 cells to charged particle beams evaluated by the detection of gammaH2AX foci. We conclude that gammaH2AX foci size is an accurate parameter to correlate the rejoining of DSBs induced by different LET radiations and radiosensitivity.
Thin Be targets for neutron production through Be(d,n) are produced and characterized. We improved and characterized the substrate surface, specifically the roughness, in order to achieve homogeneous ...and stable deposits.
Once well bonded deposits were obtained, some of them were irradiated with a 150 keV proton beam and with a 1.45 MeV deuteron beam. Both deposits, pristine and irradiated, were characterized by profilometry, X-ray diffraction, scanning electron microscopy and electron probe microanalyzer.
•Beryllium deposits on W and Mo substrates to be used as neutron generator target for AB-BNCT.•The deposits were irradiated with a 150 keV proton beam with a fluence of up to 2×1018 ions/cm2.•The Beryllium deposits were studied using many techniques before and after the irradiation.•No damage was observe on the deposits surface after the irradiation.
In this work we review all the available experimental neutron data for the (7)Li(p,n) reaction near threshold which is necessary to obtain an accurate source model for Monte Carlo simulations in ...Boron Neutron Capture Therapy. Scattered published experimental results such as cross sections, differential neutron yields and total yields were collected and analyzed, exploring the sensitivity of the fitting parameters to the different possible variables and deriving a consistent working set of parameters to evaluate the neutron source near threshold.
•Titanium deuteride thin films to be used as neutron generator target were produced and characterized.•The films were irradiated with a 150 keV proton beam with a fluence of up to ...3 × 1018 ions/cm2.•The titanium deuteride samples were studied using many techniques before and after the irradiation.•The irradiated samples shows blisters all over its surface.
Titanium deuteride thin films have been manufactured under different conditions specified by deuterium gas pressure, substrate temperature and time. The films were characterized by different techniques to evaluate the deuterium content and the homogeneity of such films. Samples with different concentrations of deuterium, including non deuterated samples, were irradiated with a 150 keV proton beam. Both deposits, pristine and irradiated, were characterized by optical profilometry and scanning electron microscopy.
New method to evaluate the 7Li(p,n)7Be reaction near threshold Herrera, María S.; Moreno, Gustavo A.; Kreiner, Andrés J.
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
04/2015, Letnik:
349
Journal Article
Recenzirano
Odprti dostop
In this work a complete description of the 7Li(p,n)7Be reaction near threshold is given using center-of-mass and relative coordinates. It is shown that this standard approach, not used before in this ...context, leads to a simple mathematical representation which gives easy access to all relevant quantities in the reaction and allows a precise numerical implementation. It also allows in a simple way to include proton beam-energy spread affects. The method, implemented as a C++ code, was validated both with numerical and experimental data finding a good agreement. This tool is also used here to analyze scattered published measurements such as (p,n) cross sections, differential and total neutron yields for thick targets. Using these data we derive a consistent set of parameters to evaluate neutron production near threshold. Sensitivity of the results to data uncertainty and the possibility of incorporating new measurements are also discussed.
Alternative sources of neutron production other than nuclear fission reactions are important priorities in medical and nuclear applications due to costs, safety and ease of operation. In this work, ...Formula omitted and Formula omitted thick targets for neutron production through Formula omitted and Formula omitted, respectively, have been manufactured and characterized by different techniques. In order to evaluate the irradiation effects on these materials, the targets were irradiated with 150 keV proton beam. A complete characterization of these samples was performed using scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Auger electron spectroscopy, X-ray photoemission spectroscopy and Raman spectroscopy. The results of these studies allowed us to establish that even though the irradiated samples present microstructural and chemical structure changes on its surface, the Formula omitted and Formula omitted thick targets were stable and would maintain their performance after proton irradiation at a fluence of Formula omitted and Formula omitted, respectively.
In this work we review all the available experimental neutron data for the 7Li(p,n) reaction near threshold which is necessary to obtain an accurate source model for Monte Carlo simulations in Boron ...Neutron Capture Therapy. Scattered published experimental results such as cross sections, differential neutron yields and total yields were collected and analyzed, exploring the sensitivity of the fitting parameters to the different possible variables and deriving a consistent working set of parameters to evaluate the neutron source near threshold.
•We review neutron experimental data for the 7Li(p,n) reaction near threshold.•A new computational method was used to study all the available published data.•A consistent description of the neutron source was derived fitting the available data.•We found that the neutron yield at 0° studied by Kononov is the most sensitive curve.•A consistent set of parameters to parametrize the Breit–Wigner formula is presented.
