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The study of the processes and mechanisms of the medium group mass nuclear systems formation (formed in reactions with protons) has both an important fundamental and practical significance. These tasks are especially important for the production of medical radionuclides, which are used for the effective early diagnosis and treatment of the various cancers. Combining the methods of radionuclide imaging with the methods of radionuclide therapy (therapy plus diagnostics—theranostics), it is possible to implement unique methods of non-surgical treatment of tumors with their precise visualization and minimal side effects. Therefore, in this work the experimental and theoretical studies of the nuclear reaction excitation functions with targets: 117Sn and 119Sn in the proton energy range of 6–18 MeV are carried out. Cross sections of the formation of antimony radionuclides are obtained for these reactions, and the mechanisms of such reactions are analyzed. Antimony radionuclides are promising for use in theranostics.

Differential cross sections for gamma-ray emission from the 107Ag (p, p′γ3-0)107Ag and 109Ag (p, p′γ3-0)109Ag reactions in the proton energy range 1200–2700 keV were measured at 90⁰ in the laboratory frame. In addition, differential cross sections for gamma-ray emission from the 107Ag(p, p′γ4-0)107Ag and 109Ag(p,p′γ4-0)109Ag reactions in the proton energy range 1310–2700 keV and 1330–2700 keV in the mentioned condition. The measurements were performed using the proton beam of the 3 MV Van de Graaff electrostatic accelerator of Nuclear Science and Technology Research Institute (NSTRI) in Tehran. Besides, the validity of the measured differential cross sections was verified through comparison between calculated thick target yields deduced from present work excitation curve and experimental thick target yield data available from literature. The overall systematic uncertainty of the measured values was estimated to be less than 8%.

A high-intensity pulsed neutron source can be constructed according to the principle of a superbooster, i.e., a neutron multiplying system of the neutron-generating target of the proton accelerator with proton energy of about 1 GeV in the subcritical reactivity modulation system. Usually, superboosters are considered to be safe and reliable nuclear facilities. However, as indicated in this paper, a powerful superbooster may prove to be less stable in operation than a pulsed reactor. Therefore, the problems of its safety call for close study.

The purpose of this study was to parametrize the in-air one sigma spot size for various energies and air gaps in pencil beam scanning (PBS) proton therapy. The current study included range shifters with a water equivalent thickness (WET) of 40 mm (RS40) and 75 mm (RS75). For RS40, the spot sizes were measured for energies ranging from 80 to 225 MeV in increments of 2.5 MeV, whereas the air gap was varied from 5 to 25 cm in increments of 2.5 cm. For RS75, the spot sizes were measured for energies ranging from 120 to 225 MeV in increments of 2.5 MeV, whereas the air gap was varied from 5 to 35 cm in increments of 2.5 cm. For both RS40 and RS75, all measurements (n = 1090) were acquired at the isocenter using a Lynx 2D scintillation detector. For RS40, the spot sizes increased from 3.1 mm to 10.4 mm, whereas the variation in spot sizes for RS75 ranged from 3.3 mm to 13.1 mm. For each range shifter, an analytical equation demonstrating the relationship of the spot size with the proton energy and air gap was obtained. The best parametrization results were obtained with the 3rd degree polynomial fits of the energy and air gap parameters. The average difference between the modeled and measured spot sizes was 0.0 ± 0.1 mm (range, − 0.24–0.21 mm) for RS40, and 0.0 ± 0.1 mm (range, − 0.23–0.15 mm) for RS75. In conclusion, the analytical model agrees within ± 0.25 mm of the measured spot sizes on a ProteusPLUS PBS proton system with a PBS dedicated nozzle.

Purpose The objective of this study was to evaluate the impact of the magnetic field regulation in conjunction with the volumetric repainting technique on the spot positions and range in pencil beam scanning proton therapy. Methods “Field regulation” — a feature to reduce the switching time between layers by applying a magnetic field setpoint (instead of a current setpoint) has been implemented on the proton beam delivery system at the Miami Cancer Institute. To investigate the impact of field regulation for the volumetric repainting technique, several spot maps were generated with beam delivery sequence in both directions, that is, irradiating from the deepest layer to the most proximal layer (“down” direction) as well as irradiating from the most proximal layer to the deepest layer (“up” direction). Range measurements were performed using a multi‐layer ionization chamber array. Spot positions were measured using two‐dimensional and three‐dimensional scintillation detectors. For range and central‐axis spot position, spot maps were delivered for energies ranging from 70–225 MeV. For off‐axis spot positions, the maps were delivered for high‐, medium, and low‐energies at eight different gantry angles. The results were then compared between the “up” and “down” directions. Results The average difference in range for given energy between “up” and “down” directions was 0.0 ± 0.1 mm. The off‐axis spot position results showed that 846/864 of the spots were within ±1 mm, and all off‐axis spot positions were within ±1.2 mm. For spots (n = 126) at the isocenter, the evaluation between “up” and “down” directions for given energy showed the spot position difference within ±0.25 mm. At the nozzle entrance, the average differences in X and Y positions for given energy were 0.0 ± 0.2 mm and −0.0 ± 0.4 mm, respectively. At the nozzle exit, the average differences in X and Y positions for given energy were 0.0 ± 0.1 mm and −0.1 ± 0.1 mm, respectively. Conclusion The volumetric repainting technique in magnetic field regulation mode resulted in acceptable spot position and range differences for our beam delivery system. The range differences were found to be within ±1 mm (TG224). For the spot positions (TG224: ±1 mm), the central axis measurements were within ±1 mm, whereas for the off‐axis measurements, 97.9% of the spots were within ±1 mm, and all spots were within ±1.2 mm.

An R-matrix analysis is performed for experimental data on 9Be(p,p0)9Be, 9Be(p,p1)9Be* (1.670 MeV), 9Be(p,p2)9Be* (2.430 MeV), 9Be(p,n0)9B, 9Be(p,d0)8Be, 9Be(p,α0)6Li, 9Be(p,α2)6Li* (3.5618 MeV), and 7Li(3He,p0)9Be reactions at 6.5–19.5 MeV excitation energies of 10B compound nucleus. Experimental data on differential and integral cross sections of the 9Be(p,α2)6Li* (3.5618 MeV, Jπ = 0+) reaction at proton energy Ep = 2.3–4.5 MeV are included in the analysis, along with data on differential cross sections of the 9Be(p,n0)9B reaction at angle 0° in the Ep = 2.2–3.5 MeV energy range. New 10B levels are determined and characteristics of states detected earlier are improved.

We studied the excitation functions of 59Co(p,x) reactions and measured the production cross-sections of medical radioisotopes (57Ni, 55,57,58Co, 54Mn, 51Cr) and other by-products (56Ni, 56Co, 56Mn) from their threshold to a proton energy of 43.7 MeV. The stacked-foil activation method was employed to irradiate the samples with an external beam from the MC-50 cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS), Korea. Off-line γ-ray spectrometry was used to measure the activities of the produced radionuclides. The integral yields for the thick target of the investigated radionuclides were also calculated from the measured excitation functions. The measured results were compared with the literature data as well as with theoretical values obtained from the TENDL-2017 library based on the TALYS-1.9 code.

The dehydroxylation mechanism of mica is studied using IR spectroscopy; x-ray structure and thermodynamic analysis; and kinetic, quantum-mechanical, and quantum-chemical methods. Dehydroxylation is shown to involve localization of a proton between two O atoms. A model in which the hydroxyl proton is placed in a double potential well is proposed. The model allows the basic features of mineral dehydroxylation to be revealed. The proton energy increases if the mineral is heated so that the barrier becomes more transparent. The probability of a particle transitioning through the barrier owing to a tunnel effect is considered. The change of this probability defines the dehydroxylation process.

We present the cross sections for the nat Zn ( p , x ) 67 Cu and nat Zn ( p , x ) 67 Ga reactions within a proton energy range of 47.5–99.2 MeV. We efficiently separated the overlapping gamma-ray spectra of the two isotopes 67 Cu and 67 Ga , using an analytical method without radiochemical separation. The present data were compared with previous data from the literature, typically obtained by radiochemical separation before measuring the gamma-ray spectra of the two isotopes. Our results for the two isotopes generally showed greater or smaller values than those reported in the literature, except for some data concerning partial energy ranges, which were in agreement with the literature data. The present data were also compared with the TENDL-2017 library based on the TALYS code.

At the proton energy of Ep = 7.4 MeV, the double-differential cross sections for the reaction 27Al(p, α1γ)24Mg were measured for 11 values of the alpha-particle emission angle in the range of θα = 30°–160°(lab). All even components of the density-matrix spin-tensors were reconstructed for the oriented 24Mg nucleus in the 2+ state at 1.369 MeV, and the polarization features of this nucleus, including the populations of magnetic sublevels of the nucleus for all spin projections, multipole-moment orientation tensors, and the quadrupole and hexadecapole tensor polarizations, were determined. Relevant experimental results were compared with their counterparts calculated for the triton-pickup mechanism within the coupled-channel method and in the statistical limit of the compound-nucleus model.

L subshell X-rays of 48Cd and 49In have been measured for the impact of protons with energies from 75 to 250 keV. Obviously, it is found that Lγ2 (abbreviation Lγ2,3 for 48Cd and Lγ2,3,4 for 49In) X-ray emission is enhanced in comparison with Lγ1 X-ray emission. The relative intensity ratios of Lγ2 to Lγ1 X-ray are larger than the atomic data and increase with decreasing proton energy. This is caused by the multiple ionization of outer-shell electrons. To verify this explanation, the enhancements for relative intensity ratio of Lι and Lβ2 to Lα X-ray in experiments are discussed, and the direct ionization cross sections of 4d, 5s, and 5p electrons are calculated using BEA theory.

The effect of low-dose proton irradiation (irradiation dose 1010–1.8 × 1011 cm–2) on the capacitance–voltage, forward current–voltage, and reverse-recovery characteristics of 4H-SiC p–no junction diodes is studied. Irradiation is performed with 1.8-MeV protons through a 10-μm-thick Ni-film (the proton energy and Ni-film thickness were chosen so that the projected proton range in silicon carbide is approximately equal to the p–no junction depth). It is shown that proton irradiation in the above doses (i) does not change the concentration of majority carriers, (ii) leads to a dramatic decrease in the lifetime of nonequilibrium carriers (at a low injection level) (by several tens of times at the highest irradiation dose), and (iii) decreases the reverse-recovery charge at a high injection level (by up to a factor of 3 at the highest irradiation dose).

We measured the excitation functions of natTa(p,x)177,178W, natTa(p,x)176,177,178m1,180gTa, and natTa(p,x)175,179m2,180mHf reactions up to the proton energy of 44.2 MeV using the stacked-foil activation technique. The measured results were compared with the literature data as well as with the theoretical values obtained from the TENDL-2017 library based on the TALYS-1.9 code. The integral yields for thick target of the investigated radionuclides were determined from the measured excitation functions. The purpose was to provide a new data set for the formation of the investigated radionuclides applicable in medicine and industry and to provide information that could support in testing and understanding the nuclear reaction theories.

The effect of proton irradiation on the electrical characteristics of high-voltage (3 kV) 4H-SiC junction diodes is studied. The diodes are irradiated through a 10-μm-thick Ni mask. The proton energy and the irradiation dose are 2.8 MeV and 4 × 1011 cm–2, respectively. After irradiation, the forward differential resistance of the diodes increased by ~35%, the reverse-recovery charge decreased by a factor of ~3, and the nature of the reverse recovery became “hard.”

The Proton Power Upgrade (PPU) project is underway at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The project will double the proton accelerator power from 1.4 MW to 2.8 MW, increase power to the First Target Station (FTS), and enable a future Second Target Station (STS). The power increase partly comes from raising proton energy from 1.0 GeV to 1.3 GeV. The STS will operate at 0.7 MW at 15 Hz when completed. Until then, PPU will provide the capability to operate the FTS at 2.0 MW at 60 Hz. Maximum power at the FTS to date has been 1.4 MW at 60 Hz with 1.0 GeV protons. A new mercury target module design to operate reliably under PPU conditions has been completed after a multi-year effort. The design philosophy and assessment of the structural analysis are described here. This target underwent an unprecedented design and analysis process for SNS using the latest engineering techniques and incorporating years of operating lessons and outcomes from R&D to meet structural design criteria. It also incorporates high-flow gas injection to further mitigate pulse fatigue stresses as well as cavitation damage to the mercury vessel.

In this study 14 kidney stones (oxalate and phosphate stones) collected from two Sudanese hospitals Particle Induced X ray Emission (µ-PIXE). This technique was used to investigate the matrix as well as the trace element compositions of kidney stones on a microscopic scale using 1.5MeV proton energy. Significant differences in elements content across the groups were found by applying statistical methods. Trace elements such as P,Ca, Fe, Ni, Cu, Zn, Se, Sr, Br, and Pb showed a possible linear relationship of the mean profile for trace elements for each group of stones. This study shows that micro analysis of urinary stones can provide complementary information on patients' exposure to epidemiological risk factors such as geography, diet and drinking water.

Many kinds of radioisotopes (RIs) produced by the high energy (100 ~ 200 MeV) proton accelerators are developed by the foreign R&D institutes and the worldwide demands are being increased continuously. The RI production using high energy proton beam higher than 50 MeV was not considerable because of the limit of the proton beam energy from existing proton accelerator facilities in Korea before 2013. The available maximum proton energy was 50 MeV from MC-50 cyclotron of Korea Institute of Radiological and Medical Sciences (KIRAMS) at that time. After the construction of a 100 MeV high-current and high-energy proton accelerator and a new irradiation facility for the RI production in 2013 and 2016 by the Korea Multi-purpose Accelerator Complex (KOMAC) at Korea Atomic Energy Research Institute (KAERI), we can make a plan for the new RI production of Cu-67, Sr-82 and so on. In the medical application fields, the worldwide demand of Sr-82 is being increased rapidly during last several years and the domestic demand of Cu-67 is also expected to be increased in near future. And alpha-emitters, such as Ac-225 and Ra-223, are becoming attractive to the users in the medical science fields in the future. The RI development plan of KOMAC was specified recently reflecting the recent environment changes and requirements from the users. In this paper, the results and present status of RI production and R&D facilities, calculation results related to the RI production yields, and future plans is presented.

Differential cross sections for the reaction channels 7Li(p,nγ1-0)7Be (Eγ = 429 keV), 7Li(p,pγ1-0) (Eγ = 478 keV), 19F(p,pγ1-0)19F (Eγ = 110 keV), 19F(p,pγ2-0)19F (Eγ = 197 keV) have been measured in the proton energy range 810–3700 keV, with an energy step of 10 keV. The reactions channels 19F(p,pγ3-1)19F (Eγ = 1236 keV), 19F(p,pγ4-1)19F (Eγ = 1349 keV), 19F(p,pγ5-2)19F (Eγ = 1357 keV) have also been investigated in the proton energy range 1915–3225 keV. The experimental set-up, the uncertainty budget, the comparison with other data and the progress assured by new data in the analytical use of standard-less Particle Induced Gamma-ray Emission (PIGE) are discussed.

We simulated a doublet of permanent magnet quadrupoles (PMQs) to estimate the sensitivity on positioning precision and its impact on the spectral properties of transported protons. The study guided the construction and testing of a focusing setup for laser-accelerated proton bunches with energies between 6 and 10 MeV. Our results shed light on possible applications that may arise from broad input particle spectra.

The Fe 58 ( p , n ) Co 58 reaction cross-section within Giant Dipole Resonance (GDR) region i.e. from 3.38 to 19.63 MeV was measured by stacked-foil activation and off-line γ-ray spectrometric technique using the BARC-TIFR Pelletron facility at Mumbai. The present data were compared with the existing literature data and found to be in good agreement. The Fe 58 ( p , n ) Co 58 reaction cross-section as a function of proton energy was also theoretically calculated by using the computer code TALYS-1.8 and found to be in good agreement, which shows the validity of the TALYS-1.8 program.

We present an improvement design of a two-dimensional (2D) angular-resolved proton spectrometer for wide-angle measurement of proton beams from high-intensity laser-solid interactions. By using a 2D selective entrance pinhole array with different periods in orthogonal axes, the angular resolution along one dimension is improved by a factor of 6.7. This improvement provides the accessibility to detect the spatial fine structures of the proton energy spectrum.

The quenching of the experimental spectroscopic factor for proton emission from the short-lived $d_{3/2}$ isomeric state in $^{151m}$Lu was a long-standing problem. In the present work, proton emission from this isomer has been reinvestigated in an experiment at the Accelerator Laboratory of the University of Jyv\"{a}skyl\"{a}. The proton-decay energy and half-life of this isomer were measured to be 1295(5) keV and 15.4(8) $\mu$s, respectively, in agreement with another recent study. These new experimental data can resolve the discrepancy in the spectroscopic factor calculated using the spherical WKB approximation. Using the R-matrix approach it is found that the proton formation probability indicates no significant hindrance for the proton decay of $^{151m}$Lu., Comment: 6 pages, 5 figures

In this study we presented a theoretical investigation of the channeling of high energy protons with the radial deformed (10, 0)@(5, 0) double-wall carbon nanotubes (DWNTs). Proton energy is varied from 0.1 to 10 GeV. The channeling potential within the deformed DWNTs is presented. A Monte Carlo (MC) simulation is used to obtain spatial and angular distributions of channeled protons with radially deformed DWNTs. We treated problem relativistically. This is the first time that we presented spatial and angular distributions of channeled protons with radially deformed DWNTs. Our results show that the spatial and angular distributions depend strongly of nanotube lengths, proton energy, and especially of level of radial deformation of nanotube. Multi-wall nanotubes (MWNTs) can be technically realised with better channeling performance then single-wall nanotubes (SWNTs) and that is why we believe that these results may be useful for production and guiding of nanosized ion beams.

The problem of creation of high energy neutrino beams on the basis of modern and future circular proton accelerators with the help of traditional technology seems to be expensive and difficult. In our previous article we proposed a new method for generation of neutrino beams for 6.5 TeV protons at the LHC based on the use of focusing bent single crystals. However, in last years there have been publications devoted to proton colliders with an energy of 50 TeV. This encouraged us to study the possibility of applying of the proposed method to generate neutrino beams at these colliders. In addition, we present some new information for proton energy 6.5 TeV.

The production cross sections of 141,143,144,146,148m,148g,149,150Pm, 139m,147,149Nd, 138m,142gPr, and 139gCe in the natNd(p,x) reactions were determined by a stacked-foil activation technique for the proton energy range up to 45 MeV using the MC-50 cyclotron of Korea Institute of Radiological and Medical Sciences. The measured cross sections were compared with literature data as well as data from the TENDL-2014 library based on TALYS 1.6. The production cross sections of the above radionuclides are slightly higher than the literature data but are in general agreement with values in TENDL-2014 library except for 148mPm, 148gPm, 139mNd, and 142gPr. The thick target integral yields of the produced radionuclides were also deducted from the measured cross sections.

Based on the irradiation damage model of solar cells, the irradiation damage mechanism of space solar cells from the aspect of the carriers’ transport is studied. The basic rules of electrical parameter degradation of GaAs/Ge solar cells under different energy proton and electron irradiation are obtained through the ground-accelerated equivalent simulation test for space-charged particles. The open-circuit voltage degradation curves of the solar cells are fitted nonlinearly by its mathematical model. The change laws of damage coefficient of majority carriers’ removal rate with the incident proton and electron energy are given. The damage coefficient of GaAs/Ge solar cells first increases and then decreases with increasing incident proton energy, and it reaches a maximum at 100 keV proton irradiation. In addition, the damage coefficient increases with increasing incident electron energy. The studies show that open-circuit voltage degradation is closely related to the removal effect of the majority carriers under charged particle irradiation. The results have important significance to reveal the irradiation damage mechanism of the space solar cells.

In this article, 3 MeV proton irradiation-induced degradation in InP/InGaAs double heterojunction bipolar transistors (DHBTs) is studied, the fluence up to 5 × 10 12 protons/cm 2 , meanwhile 10 MeV proton irradiation is investigated in order to compare the differences induced by different proton energy irradiation. The devices exhibit good tolerance up to 5 × 10 11 protons/cm 2 . The concentration of vacancies at different proton fluences can be calculated from SRIM. Being donor-like defects, the In and Ga vacancies act as compensation center while As vacancy acts as an acceptor-like defect. Adding the vacancies model into Sentaurus device simulator, simulation results match well with the trends of measured data.

The 100-MeV proton linacs of the Korea Multi-purpose Accelerator Complex (KOMAC) started machine operation in 2013, and a 20-MeV or a 100-MeV proton beam has been provided to users who want to utilize a proton beam for their research and development at the KOMAC. Under proton beam irradiation, the target material will experience radiation damage induced by the proton beam, and this radiation damage can be evaluated as a function of the displacement per atom (DPA). Therefore, we used the SRIM (stopping and range of ions in matter) to investigate the damage rate induced by a 20-MeV or a 100-MeV proton beam. In this paper, we will introduce the results obtained by using SRIM calculation, for the radiation damage as a function of the proton energy, beam current, target material and target dimension.

The independent isomeric yield ratios of 148Pm from the natSm(γ, x) reaction at the end-point bremsstrahlung energy of 45–64 MeV have been determined using an off-line γ-ray spectrometric technique at the 100 MeV electron linac of Pohang accelerator laboratory, Pohang, Korea. We also have determined the isomeric yield ratios of 148Pm from the natNd(p,xn) reactions in the proton energy of 5.08–44.72 MeV by a stacked-foil activation and an off-line γ-ray spectrometric techniques at the MC-50 cyclotron of the Korean Institute of Radiological and Medical Sciences, Korea. The determined isomeric yield ratios of 148Pm were compared with literature data and theoretical values estimated by the TALYS 1.4. The present data along with the similar data from literature at other energies shows that the isomeric yield ratio of 148Pm increases with the excitation energy both in the natSm(γ, x) and the natNd(p, xn) reactions. The isomeric yield ratios of 148Pm from the natNd(p, xn) reactions are always higher than those from the natSm(γ, x) reactions at the same excitation energy, which indicate the role of input angular momentum besides excitation energy.

In the framework of the Hartree-Fock approach the proton spin-orbital splittings of the 1p orbits and the shell gaps in the oxygen isotopes are investigated with the interactions SLy5+T,SLy5+Tw, SGII+Te1, SGII+Te2, SGII+Te3 and many sets of the TIJ interactions. All of the interactions are the Skyrme interactions and contain a tensor component (tensor force). It is shown that the evolution of the single-proton levels for the oxygen isotopes is sensitive to a parameter β T which is associated with the tensor force strength of the Skyrme interactions. To understand this phenomenon, we systematically analyze the dependence of the spin-orbit splittings and shell gaps on the parameter β T in terms of the spin-orbit potential and the corresponding wave function. We find that the Skyrme interactions can be classified into two groups: (a) T21, T32, T43, T54, SLy5+T, SLy5+Tw, SGII+Te1 and SGII+Te2, which can roughly reproduce the experimental shell gaps of the oxygen isotopes; (b) T1J and SGII+Te3, which can not reproduce the experimental shell gaps.

The available experimental data on the relative thermoluminescent efficiency of the LiF:Mg,Ti dosimetric peaks for protons are contradictory. There are several reports showing that the efficiency exceeds unity by even more than 30%, however, many others show the efficiency close to unity or even lower. These contradictory data might be a result of the real variability of TLD properties or of not perfectly reproduced experimental conditions. In an attempt to resolve this issue, the efficiency of 16 batches of LiF:Mg,Ti (MTS) detectors for 60 MeV protons produced at the IFJ Krakow over the last 20 years was measured. All values of the relative TL efficiency were found to exceed unity significantly, with an average of 1.09. Dispersion between different batches was very low, all data were within 4% of the mean value. In second part of experiment the dependence of the relative efficiency of LiF:Mg,Ti and LiF:Mg,Cu,P detectors on proton energy was determined. The efficiency for LiF:Mg,Ti dosimetric peaks was found to have a maximum of 1.20 at about 20 MeV. For LiF:Mg,Cu,P the relative efficiency decreases systematically with decreasing proton energy, from 0.96 at 56 MeV, to 0.61 at 11 MeV.

A realistic density-dependent nucleon–nucleon (NN) interaction with finite-range exchange part which produces the nuclear matter saturation curve and the energy dependence of the nucleon–nucleus optical model potential is used to calculate the preformation probability, S α , of α-decay from different isotones with neutron numbers N = 124 , 126 , 128 , 130 and 132 . We studied the variation of S α with the proton number, Z, for each isotone and found the effect of neutron and proton energy levels of parent nuclei on the behavior of the α-particle preformation probability. We found that S α increases regularly with the proton number when the proton pair in α-particle is emitted from the same level and the neutron level sequence is not changed during the Z-variation. In this case the neutron–proton (n–p) interaction of the two levels, contributing to emission process, is too small. On the contrary, if the proton or neutron level sequence is changed during the emission process, S α behaves irregularly, the irregular behavior increases if both proton and neutron levels are changed. This behavior is accompanied by change or rapid increase in the strength of n–p interaction.

Recently the ANSTO heavy ion microprobe has been used for elemental mapping of thin brain tissue sections. The fact that a very small portion of the proton energy is used for X-ray excitation combined with small variations of the major element concentrations makes μ-PIXE imaging and GeoPIXE analysis a challenging task. Excitotoxic brain injury underlies the pathology of stroke and various neurodegenerative disorders. Large fluxes in Ca +2 cytosolic concentrations are a key feature of the initiation of this pathophysiological process. In order to understand if these modifications are associated with changes in the elemental composition, several brain sections have been mapped with μ-PIXE. Increases in Ca +2 cytosolic concentrations were indicative of the pathophysiological process continuing 1 week after an initiating neural insult. We were able to measure significant variations in K and Ca concentration distribution across investigated brain tissue. These variations correlate very well with physiological changes visible in the brain tissue. Moreover, the obtained μ-PIXE results clearly demonstrate that the elemental composition changes significantly correlate with brain drauma.

The semi-empirical cross sections have been deduced by individual fittings of the updated experimental data (from 1980 till 2009) and normalized to their corresponding theoretical values (ECPSSR model) for elements with 72≤ Z ≤90 by protons energies varying from 0.1 to 4.0 MeV. Also, based on the individual fittings of the elements and the remarkable deviation of the experimental data from the ECPSSR values for low proton energy, we attempt to deduce another semi-empirical cross sections by introducing the low–high proton energy procedure which separates the fitting of the semi-empirical cross sections for low proton energy from those for high proton energy. Our results are presented for selected heavy elements. Finally, a comparison is made between our results and the experiment.

The recently developed PIC code MANDOR features arbitrary target design including 3D preplasma and the 6-component laser fields of a tightly focused laser beam. The 3D simulations have been performed to model recent HERCULES experiments on proton acceleration, where protons with energy greater than 20 MeV were produced using just 1.5 J laser pulses focused to intensity of 2 × 1021 W/cm2. By adapting the 3D target geometry relating to ps-prepulse effect, reasonable agreement with experimental data for the proton energy spectrum has been achieved. The effect of the 3D preplasma shape on efficiency of proton acceleration is discussed. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In proton beam therapy, changes in the proton range due to lateral heterogeneity may cause serious errors in the dose distribution. In the present study, the pencil-beam redefinition algorithm (PBRA) was applied to proton beam therapy to address the problem of lateral density heterogeneity. In the calculation, the phase-space parameters were characterized for multiple range (i.e. proton energy) bins for given pencil beams. The particles that were included in each pencil beam were transported and redefined periodically until they had stopped. The redefined beams formed a detouring path that was different from that of the non-redefined pencil beams, and the path of each redefined beam was straight. The results calculated by the PBRA were compared with measured proton dose distributions in a heterogeneous slab phantom and an anthropomorphic phantom. Through the beam redefinition process, the PBRA was able to predict the measured proton-detouring effects. Therefore, the PBRA may allow improved calculation accuracy when dealing with lateral heterogeneities in proton therapy applications.

The paper has studied the influence of target material and thickness on energy and angular distributions of the protons generated by using an 800 nm, 60 fs, 0.24 J laser pulse to irradiate solid target foils. The results show that the initial density and thickness of the targets will affect the formation of the acceleration sheath fields in the target normal direction. For the same target thickness, using lower density target materials can obtain a higher proton maximum energy. However, lower density targets tend to be deformed due to the shock waves launched by the laser pulses, making the proton spatial distribution more divergent.

The cross-section of the O16(p,γ)F17 reaction is well studied at low energies. It can be used for analytical purposes to extract the oxygen content of thin samples or surface layers of bulk samples from the measured γ-ray yield. Here we recommend absolute cross-sections for the laboratory proton energy range from 500 to 2500 keV, where the cross-sections are non-resonant and thus vary smoothly with energy.

In order to improve the total laser-proton energy conversion efficiency, a nanobrush target is proposed for proton acceleration and investigated by two-dimensional particle-in-cell simulation. The simulation results show that the nanobrush target significantly enhances the energy and number of hot electrons through the target rear side. Compared with plain target, the sheath field on the rear surface is increased near 100% and the total laser-proton energy conversion efficiency is prompted more than 70%. Furthermore, the proton divergence angle is less than 30° by using nanobrush target. The proposed target may serve as a new method to increase the energy conversion efficiency from laser to protons.

The natLu(p,x)175Hf excitation function was measured and a maximum cross section of 128 ± 14 mb was observed at a proton energy of 10.6 MeV. The experimentally determined cross sections were compared to theoretical values using the HIVAP and TALYS codes.

Based on the idea that the simplest double-\(\bar{K}\) nuclear cluster, K − K − pp, can be produced in the p + p → K + + K + + Λ* + Λ* →K + + K + + K − K − pp reaction, where Λ* = Λ(1405) is a quasi-bound state K − p, we have calculated the differential cross sections for this process and found out that a peak of K − K − pp dominates in the mass spectrum when the cluster is a deeply bound and dense system, helped by a very large momentum transfer Q ∼ 1.8 MeV/c. The appropriate incident proton energy for this process is around 7 GeV. We found that, the deeper and denser the bound system is, the larger its population becomes. The K −-K − repulsion inside K − K − pp is shown to give only a small change on the bound-state structure and the cross section.

ISIS is a world leading centre for research in the physical and life sciences at the Rutherford Appleton Laboratory. ISIS is used primarily for neutron production but it is also an intense source of pulsed muons. Muon target optimisation studies were performed with the Geant4 code as restrictions are imposed on target thickness, as this will affect the proton transmission to the second neutron target. In this paper we investigate the impact of incident proton energy on muon production and possible target geometries and target materials.

A numerical optimization of a Beam Shaping Assembly (BSA) for Accelerator Based-Boron Neutron Capture Therapy (AB-BNCT) has been performed. The reaction (7)Li(p,n)(7)Be has been considered using a proton beam on a lithium fluoride target. Proton energy and the dimensions of a simple BSA geometry have been varied to obtain a set of different configurations. The optimal configuration of this set is shown.

Based on 3D particle-in-cell (PIC) simulations a comparative analysis of laser-triggered proton generation from the interaction of short high-intensity laser pulses with ultrathin foils and dense gas jets has been performed. It has been shown that for ultra-relativistic laser intensities the use of low-density targets with near critical density (aerogel or dense gas jet) has no advantage in comparison with ultrathin foils in terms of maximum proton energy and spectrum quality. Utilization of mass-limited foils with submicron thickness demonstrates even greater superiority for overdense targets and allows one to produce monoenergetic proton beams with energies of hundreds of mega-electron-volts by using high-contrast laser pulses with energies of the order of tens of Joules.

Cross-sections for the proton induced reactions on natural molybdenum leading to (93m)Tc, (93m+g)Tc, (94)Tc, (94m)Tc, (95)Tc, (95m)Tc, (96m+g)Tc, (99m)Tc, (90)Mo, (93m)Mo, (99)Mo, (90m+g)Nb, (92m)Nb, (95)Nb and (89m+g)Zr were measured in the proton energy range 8.4-37.1MeV on the cyclotron U-120M at the Institute of Nuclear Physics AS CR. Special attention was paid to excitation functions and thick target yields for the formation of (95m)Tc, a suitable tracer for (99)Tc, of (96m+g)Tc, which was proposed as a proton beam monitor, and of (99m)Tc and (99)Mo, the most widespread radionuclide generator pair in nuclear medicine. If appropriate, obtained data are compared with the heretofore published cross-sections.

The excitation function of the proton exchange reactions on gold was investigated in the energy range from threshold up to 20MeV. We presented our experimental results upto 14MeV stacked-foil technique was used, the target was of high purity gold foils (99.99%.) Reactions cross-sections and excitation functions were studied. Both isomeric level cross sections of (197)Hg were measured and calculated theoretically using the DDHMS routine of the EMPIRE-II (v2.19) code. Isomeric cross-section ratios for the pair (197m,g)Hg were calculated and presented as a function of proton energy.

We have analyzed the acceleration of laser-generated protons, produced at the rear surface of flat-cone targets irradiated by an ultra-intense (I∼5×1019 W/cm2) short (400 fs) laser pulse. We used different target sizes and shapes in order to find the optimum target layout. We find that for targets with a too narrow cone structure, the production of the hot electrons, driving the proton acceleration, is located prior to the accelerating rear surface of the target, resulting in a reduced maximum proton energy.