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Purpose: Positron emitting isotopes such as 11 C and 10 C can be used for vital dose verification in hadron therapy. These isotopes are produced when the high energy 12 C primary beam particles undergo nuclear reactions within the patient., Methods: We discuss a model for calculating cross sections for the production 11 C in 12 C+ 12 C collisions, applicable at hadron therapy energies., Results: Good agreement with the available cross section measurements is found for 12 C(-1n), though more detailed, systematic measurements would be very valuable., Conclusions: Nuclear structure plays a crucial role in the reactions of light nuclei, particularly when those reactions are peripheral and involve only a few nucleons. For such reactions, nuclear structure has a strong influence on the energy and angular distribution of the cross section, and is an important consideration for reliable dose verification using 11 C in hadron therapy., (Copyright © 2016. Published by Elsevier Ltd.)

Context. The production of neutron-rich elements at neutron densities intermediate to those of the s- and r-processes, the so-called i-process, has been identified as possibly being responsible for the observed abundance pattern found in certain carbon-enhanced metal-poor (CEMP) stars. The production site may be low-metallicity stars on the asymptotic giant branch (AGB) where the physical processes during the thermal pulses are not well known. Aims. We investigate the impact of overshoot from various convective boundaries during the AGB phase on proton ingestion events (PIEs) and the neutron densities as a necessary precondition for the i-process as well as on the structure and continued evolution of the models. Methods. We therefore analyzed models of a 1.2 M⊙, Z = 5 × 10−5 star. A fiducial model without overshoot on the AGB (overshoot was applied during the pre-AGB evolution) serves as a reference. The same model was then run with various overshoot values and the resulting models were compared to one another. Light element nucleosynthesis is also discussed. Additionally, we introduce a new timescale argument to predict PIE occurrence to discriminate between a physical and a numerical reason for a nonoccurrence. A comparison to observations as well as previous studies was conducted before finally presenting the most promising choice of overshoot parameters for the occurrence of the i-process in low-mass, low-metallicity models. Results. The fiducial model reveals high neutron densities and a persistent split of the pulse-driven convection zone (PDCZ). Overshoot from the PDCZ results in either temporary or permanent remerging of the split PDCZ, influencing the star's structure and evolution. While both overshoot and non-overshoot models exhibit PIEs generating neutron densities suitable for the i-process, they lead to varied C/O and N/O ratios and notable Li enhancements. Comparison with previous studies and observations of CEMP-r/s stars suggests that while surface enhancements in our models may be exaggerated, abundance ratios align well. Though, for high values of overshoot from the PDCZ the agreement becomes worse. [ABSTRACT FROM AUTHOR]

This paper considers secondary neutrons contribution to the yield of 99mTc obtained from the thick Mo-sample via (p,2n) nuclear reaction channel. The physical yield was determined experimentally using 11-MeV cyclotron Eclipse RD with application of the new target assembly developed for solid sample irradiations and appeared to be 30.9 ± 1.3 MBq/μAh. The neutron flux over the sample was analyzed by MCNP simulations taking into account the construction elements of the target module and cyclotron self-shielding. The contribution to the 99mTc yield by indirect production via 98Mo(n,γ)99Mo → 99mTc reactions was estimated. [ABSTRACT FROM AUTHOR]

Recent studies of the neutrino-driven wind from proto-neutron stars have indicated that the wind is likely proton rich for much of its lifetime, and the high flux of neutrinos can induce νp-process nucleosynthesis allowing for the formation of heavy elements. It has also been shown that gravito-acoustic waves, generated by convection within the proto-neutron star, can significantly alter the dynamics and nucleosynthesis in the wind. Therefore, we present a study of the effects of convection-driven waves on the nucleosynthesis in proton-rich neutrino-driven winds, focusing on the νp-process. We find that wave effects can strongly impact νp-process nucleosynthesis even at wave luminosities a factor of 10−5 smaller than the total neutrino luminosity. The momentum flux of the waves accelerates the wind, reducing the net neutrino heating and the persistent neutron abundance created by p (⁠|$\bar{\nu }_\mathrm{ e},e^+$|⁠), which impedes νp-process nucleosynthesis. However, this effect is generally counteracted by the effects of waves on seed nucleus formation, as the acceleration of the wind and the heating that occurs as these waves shock both favour a more α-rich environment with very little heavy seed nucleus formation. Overall, higher wave luminosities correlate (albeit non-monotonically) with heavier element νp-processing, up to A ≈ 200 in some cases. At very high wave luminosities (≳10−3 L ν), early shock heating by the waves disrupts α recombination, and drives a suppressed, fast-outflow r-process proceeding up to A ≈ 200. This occurs despite an assumed neutrino spectrum that predicts a proton-rich wind with equilibrium Y e = 0.6. [ABSTRACT FROM AUTHOR]

A new physics-based compact model, which makes it possible to simulate in a unified way the neutrons and protons of cosmic ray-induced SEU cross-sections, including the effects from nuclear reaction products and from direct ionization by low-energy protons, has been proposed and validated. The proposed approach is analytical and based on explicit analytical relationships and approximations with physics-based fitting parameters. GEANT4 or SRIM numerical calculations can be used as an aid to adjust or refine the phenomenological parameters or functions included in the model, taking into account real geometrical configurations and chemical compositions of the devices. In particular, explicit energy dependencies of the soft error cross-sections for protons and neutrons over a wide range of nucleon energies were obtained and validated. The main application areas of the developed model include space physics, accelerator studies high energy physics and nuclear experiments.

This paper presents a study of both the elastic and inelastic scattering of a deuteron beam on 13 C at laboratory energy of 18 MeV. The first 10 excited states of the carbon isotope were studied in terms of single-particle and collective models of excitation. Experimental cross sections were obtained by the well-known Δ E–E method. Elastic scattering data were analyzed using an optical model including a nucleus–nucleus interaction potential, while inelastic scattering data were processed using the coupled-channels approach. For the single-particle model, the spectroscopic amplitudes were obtained through calculations of the large-scale shell model with the YSOXT effective NN-potential. A double folding potential was obtained for the d + 13 C system. A comparison of model calculations with the experimental cross sections was demonstrated. The extracted deformation parameters and calculated spectroscopic information are shown in tables. The ability of the collective model to describe all excited states was demonstrated by good agreement when comparing the calculated cross sections in the collective model and experimental data. The single-particle model turned out to be significant only for the excited state of 3.09 MeV. The dominant role in the formation of the corresponding cross section is played by the 12 C ground state core with the 2 S 1 / 2 neutron. [ABSTRACT FROM AUTHOR]

This article describes the preparation of 99Mo isotope using the direct nuclear reaction 98Mo(n,γ)99Mo by neutrons of the WWR-K reactor using molybdenum (VI) oxide of natural and enriched composition, according to the isotope 98Mo (98.66%) as a target. The possibility of using enriched 98Mo oxide to produce 99Mo was considered. The estimation of the maximum specific activity of 99Mo was obtained in a comparative manner under the same irradiation conditions at the reactor. [ABSTRACT FROM AUTHOR]

Several intense energy irradiation testing facilities are functional to study the effects of radiation damage in fusion materials. Tungsten is a potential candidate material to build the plasma-facing armour components of fusion reactors. Therefore, it is vital to estimate the radiation-induced primary damage in the material, particularly due to the large amount of transmutation nuclides produced in the high-energy neutron sources. The basic evaluated nuclear data libraries provide the essential neutron reaction data to estimate the transmutations and their effects during irradiation. However, much of the important high-energy neutron reaction data are often not explicitly provided to directly study their impact on radiation damage. Such inexplicit nuclear reaction data, especially for the transmutation nuclides, can have a significant effect on the estimation of primary radiation damage. A new specific methodology has been developed to unravel information from these inexplicit nuclear reaction data from the basic ENDF-6 libraries and use them with explicit data for estimating the primary radiation damage. The energy distributions of transmuted nuclides (the recoil nuclei in general) and light charged particles produced as a result of several types of neutron–nucleus interactions in tungsten, are quantified using the cross-sections from ENDF / B-VIII.0 and TENDL-2019 basic evaluated nuclear data libraries and their inter-comparisons are carried out. The neutron-induced atomic displacements and heating in tungsten are estimated for irradiations under the fusion and IFMIF-DLi neutron spectra. It shows that the transmutation reactions under these neutron spectra can sometimes contribute more than 50% of the total primary damage, most of which can be from inexplicit nuclear reaction data. Significant differences between the two sources of basic evaluated nuclear data libraries, especially in the production of transmutation nuclides and consequently, in their contributions to damage are observed. The present study helps to illustrate the importance of inexplicit nuclear reaction data and the usefulness of the ENDF-6 libraries for estimating primary radiation damage due to transmutations in plasma-facing materials. [ABSTRACT FROM AUTHOR]

We calculate the Big Bang nucleosynthesis abundances for helium-4 and deuterium for a range of neutron lifetimes, τn = 840–1050 s, using the state-of-the-art Python package PRyMordial. We show the results for two different nuclear reaction rates, calculated by NACRE II and the PRIMAT collaborations. [ABSTRACT FROM AUTHOR]

In this work, the radiation response of bulk GaN and Ga2O3 materials exposed to ground-level neutrons is studied by Geant4 numerical simulation, considering the whole atmospheric neutron spectrum at sea level, from thermal to high energies (GeV). The response of the two materials is compared in terms of the number and type of interactions and the nature of the secondary products produced, particularly in nuclear reactions. Our results highlight the importance of 14N(n,p)14C neutron capture in the radiation response of GaN, leading to large differences in the behavior of the two materials in terms of susceptibility to thermal and intermediate-energy (below 1 MeV) neutrons. [ABSTRACT FROM AUTHOR]

Fast and high‐linearity detection of fast neutron is vital for special nuclear material seeking, nuclear accident emergency response, nondestructive neutron imaging, and neutron cancer therapy. Neutron scintillators with fast time resolution and linear energy response are indispensable for precisely acquiring the energy and temporal evolution of fast neutron, but none of the conventional neutron scintillators, whether organic, two‐component or inorganic, have performed well in this regard. To address these challenges, it is urgent to develop novel neutron scintillators. Here, 2D hybrid perovskite single crystals (C4H12N)2PbBr4 (BA2PbBr4) successfully combined with fast response time of 2.66 ns and linear energy response to fast neutrons, γ ray, and α particle, is reported. The rapid response time and linear energy response of 2D hybrid perovskite scintillator originate from intensive states density of lead halide frameworks, which are the key fluorescence emitters under neutron irradiation. This effectively suppresses the ionization quenching effect during the fluorescence process. This work represents a milestone in fast neutron detection, demonstrating a new type of neutron scintillator based on 2D hybrid perovskite single crystals with fast and high‐linearity detection characteristics, having great potential in high precision neutron spectrum measurement and nuclear reaction kinetics monitoring. [ABSTRACT FROM AUTHOR]

The cross sections for the reactions 132Xe(n,d*)131I and 134Xe(n,d*)133I were measured at energies around 14 MeV. The neutron fluence standard corresponds to the cross-section of the monitor reaction 93Nb(n,2n)92mNb. The facilities from the China Academy of Engineering Physics (CAEP) were used for this experimental study. High purity, high-pressure, and highly enriched 132,134Xe isotope gases were used as the target sample. The T(d,n)4He reaction was used as a neutron source to generate neutrons with an energy of 14 MeV. The activities of the resulting residual product were measured using an HPGe detector. The corrected experimental parameters include the geometric properties and solid angle of the sample, as well as the effects of coincidence summation and self-attenuation of the gamma ray. The covariance analysis technique is employed to derive the uncertainty and correlation matrix of the cross section. The cross sections of the reactions 132Xe(n,d*)131I and 134Xe(n,d*)133I have experimentally been determined and reported for the first time. The TALYS-1.96 program was used to derive the theoretical excitation function curves for the nuclear reactions 132Xe(n,d*)131I and 134Xe(n,d*)133I. All results are compared, including experimental measurement, theoretical calculation, and evaluation. The reaction cross section obtained for the first time plays an important role in enhancing the database and evaluating the excitation function. [ABSTRACT FROM AUTHOR]

A compact scheme of the inertial electrostatic confinement with reverse polarity based on the nanosecond vacuum discharge (NVD) enables acceleration of ions to energies sufficient for initiation of nuclear reactions. For example, the deuterium ions are accelerated in the field of a virtual cathode (in a potential well), and nuclear DD fusion can occur upon their head-on collisions with energies of ~100 keV. If the potential well in the vacuum discharge turns out to be filled by deuterium-containing clusters, there appears an additional, "accelerated ion–cluster" channel of the DD fusion. In the present work, we discuss and analyze the role of a cluster target in generation of the DD neutrons in an NVD. [ABSTRACT FROM AUTHOR]

The deuteron is a loosely bound system that can easily break up into its constituent proton and neutron whilst in the presence of Coulomb and nuclear fields. Previous experimental studies have shown that this breakup process has a significant impact on residual-nucleus production from deuteron bombardment in the high-energy range of 50–210 MeV/nucleon. However, there remains a lack of cross-section data at energies below 50 MeV/nucleon. The current study determined 93Zr + d reaction cross sections under inverse kinematics at approximately 28 MeV/nucleon using the BigRIPS separator, OEDO beamline, and SHARAQ spectrometer. Cross sections from this research were compared with previous measurements and theoretical calculations. The experimental results show a large enhancement of the production cross sections of residual nuclei, especially those produced from a small number of particle emissions, compared to the proton-induced reaction data at similar bombarding energy. The DEURACS calculation, which quantitatively takes deuteron-breakup effects into account, reproduces the data well. As a long-lived fission product, 93Zr remains a challenge for nuclear-waste disposal and treatment. This study's low-energy data may assist future consideration of nuclear-waste treatment facilities, where 93Zr + d may feasibly transmute the waste into short-lived/stable nuclei. [ABSTRACT FROM AUTHOR]

In sum, 11 (p,xn) related nuclear reactions with 9 target materials, namely 18O(p,n)18F, 15N(p,n)15O, 68Zn(p,n)68Ga, 68Zn(p,2n)67Ga, 69Ga(p,2n)68Ge, 89Y(p,n)89Zr, 100Mo(p,pn)99Mo, 100Mo(p,2n)99mTc, 112Cd(p,2n)111In, 124Xe(p,2n)123Cs and 203Tl(p,3n)201Pb, are involved in the operation of 13 radionuclide-production cyclotrons in Taiwan. The secondary neutrons accompanying these production routes could induce varying degrees of material activation in the cyclotron facility. Accordingly, this study compared the effects of various (p,xn) production routes on the neutron-induced long-lived radioactivity in the concrete walls of a hypothetical cyclotron vault. In addition, an activation-reduction approach involving the addition of a layer of neutron-absorbing material to the surface of inner concrete walls was evaluated. [ABSTRACT FROM AUTHOR]

Neutrons do not directly ionise the medium they pass through, unlike charged particles. Neutron detection is then based on nuclear reactions in which the neutron is typically lost and charged particles and/or γ-rays are generated in the final state. These are subsequently detected by appropriate sensors of various types, such as gas, scintillation, and solid-state detectors. Neutrons generated at large scale facilities (fission reactors or accelerator-driven plants) typically cover a very wide energy range. The nuclear reactions that are found to be effective at different energies make neutron detection on the one hand complex from an instrumental point of view, and on the other hand interesting from the point of view of the physics underlying the approach to be used. This article aims at presenting and discussing the main features of the nuclear reactions of interest in neutron detection in different energy ranges, and the physical processes that take place in typical sensors used as detection tools. This approach is intended to describe the entire physical process, from neutron-nucleus interaction to the physical sensor response, that represents the detection event. [ABSTRACT FROM AUTHOR]

Based on new modern data regarding the state of the fuel-containing masses (FСM) of the “Shelter”, as well as taking into account the neutron incident of 1990 and the physical properties of the FCM of the “Shelter”, the possibility of the occurrence and development of a self-sustaining chain nuclear fission reaction was considered in the FCM. It is shown that the drying of the FСM can lead to the occurrence of a single neutron burst with an amplitude comparable to the amplitude of neutron oscillations in 1990. It is also shown that the amplitude of the burst can be reduced if the rate of drying of the FCM is increased. The evaluations show that such a burst would have no impact on the environment. [ABSTRACT FROM AUTHOR]

A significant amount of alpha particles, upto ∼ 35 MeV are produced in the reactor environment. Alpha induced reaction on natural Zirconium, a reactor component, upto 40 MeV has been measured using stacked foil activation technique. The total neutron production cross section from all possible channels for α energies upto 35 MeV is also estimated using TALYS 1.96. The isomeric cross section ratio for the production of the radionuclide 95 N b has been measured and reported for the first time. [ABSTRACT FROM AUTHOR]

We report on the first experiment dedicated to the study of nuclear reactions on dopants in a cryogenic capsule at the National Ignition Facility (NIF). This was accomplished using bromine doping in the inner layers of the CH ablator of a capsule identical to that used in the NIF shot N140520. The capsule was doped with 3 × 1016 bromine atoms. The doped capsule shot, N170730, resulted in a DT yield that was 2.6 times lower than the undoped equivalent. The Radiochemical Analysis of Gaseous Samples (RAGS) system was used to collect and detect 79Kr atoms resulting from energetic deuteron and proton ion reactions on 79Br. RAGS was also used to detect 13N produced dominantly by knock-on deuteron reactions on the 12C in the ablator. High-energy reaction-in-flight neutrons were detected via the 209Bi(n,4n)206Bi reaction, using bismuth activation foils located 50 cm outside of the target capsule. The robustness of the RAGS signals suggests that the use of nuclear reactions on dopants as diagnostics is quite feasible. [ABSTRACT FROM AUTHOR]

Based on new modern data regarding the state of the fuel-containing masses (FСM) of the “Shelter”, as well as taking into account the neutron incident of 1990 and the physical properties of the FCM of the “Shelter”, the possibility of the occurrence and development of a self-sustaining chain nuclear fission reaction was considered in the FCM. It is shown that the drying of the FСM can lead to the occurrence of a single neutron burst with an amplitude comparable to the amplitude of neutron oscillations in 1990. It is also shown that the amplitude of the burst can be reduced if the rate of drying of the FCM is increased. The evaluations show that such a burst would have no impact on the environment. [ABSTRACT FROM AUTHOR]

Total neutron cross-sections for iron group nuclei with energies 30 MeV ≤ E n ≤ 100 MeV have been theoretically calculated, for ℓ ≠ 0 case. In this work, the collision matrix has been modified for a smooth spherical optical potential, which varies slowly with distance inside of target nucleus. Results agree well with the experimental data and TALYS 1.9 code. It has been found that a finite number of the angular momentum will contribute appreciably to the nuclear reaction. This study on smooth optical potential leads to useful insights into the mechanisms of neutron induced reactions, particularly for medium nuclei at high energies. [ABSTRACT FROM AUTHOR]

The paper reviews the recent progress in the description of isospin-symmetry breaking within the nuclear shell model and applications to actual problems related to the structure and decay of exotic neutron-deficient nuclei and nuclei along the N = Z line, where N is the neutron number and Z the atomic number. The review recalls the fundamentals of the isospin formalism for two-nucleon and many-nucleon systems, including quantum numbers, the spectrum's structure and selection rules for weak and electromagnetic transitions; and at the end, summarizes experimental signatures of isospin-symmetry breaking effects, which motivated efforts towards the creation of a relevant theoretical framework to describe those phenomena. The main approaches to construct accurate isospin-nonconserving Hamiltonians within the shell model are briefly described and recent advances in the description of the structure and (isospin-forbidden) decay modes of neutron-deficient nuclei are highlighted. The paper reviews major implications of the developed theoretical tools to (i) the fundamental interaction studies on nuclear decays and (ii) the estimation of the rates of nuclear reactions that are important for nuclear astrophysics. The shell model is shown to be one of the most suitable approaches to describing isospin-symmetry breaking in nuclear states at low energies. Further efforts in extending and refining the description to larger model spaces, and in developing first-principle theories to deal with isospin-symmetry breaking in many-nucleon systems, seem to be indispensable steps towards our better understanding of nuclear properties in the precision era. [ABSTRACT FROM AUTHOR]

For the problem of two or more nuclear reactions producing the same product nucleus in the actual cross-section measurements of nuclear reactions, a method is given for subtracting the effect of interference reactions that produce the same product nucleus on the cross-section measurements of the target nuclear reaction. The cross-section values were measured for the 183W(n,p)183Ta reaction at four different neutron energies from 13.5 to 14.8 MeV using the activation technique. In the process of calculating the cross-section data, the effects of the interference reactions 184W(n,d)183Ta and 184W(n,n+p)183Ta were subtracted using the above method. At the same time, the effect of the 186W(n, α)183Hf → β − 183Ta process was also subtracted by using the previously developed method. Analysis and comparison show that our experimental cross-section values for the 183W(n,p)183Ta reaction agree with the previous results in the case of using the samples of enriched 183W at close energies. Discrepancies in the previous cross-section data of the 183W(n,p)183Ta reaction are clarified, and the recommendation excitation function curve for the 183W(n,p)183Ta reaction is given by adopting the nuclear theoretical model program system TALYS-1.95. [ABSTRACT FROM AUTHOR]

47Sc for theranostic medical applications was produced from the neutron activation of a natural calcium target. Liquid–liquid extraction for separation of the 47Sc radioisotope from 47Ca was carried out with the extractant Cyanex 272 ((2,4,4-trimethylpentyl) phosphinic acid). The effects of various extraction parameters on the extraction efficiency and separation of the two radionuclides were investigated, including the extraction time, pH, metal ion concentrations, extractant concentration, diluent type, and phase ratio. It was shown that the extraction yield of the 47Sc radioisotope with the proposed procedure is about 90%, with a fast separation time of 10 min, at pH 1.8 (0.01 M HCl), and with low E (1%) for 47Ca and high separation factors. The stripping % of the loaded 47Sc isotope was about 99.2% using 0.4 M oxalic acid solution with a purity of 99.9%. [ABSTRACT FROM AUTHOR]

Evaluated spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented for 24N, 24O, 24F, 24Ne, 24Na, 24Mg, 24Al, and 24Si. This evaluation for A=24 supersedes the earlier one by R. B. Firestone (2007Fi14). Highlights of this evaluation are the following: In 24O, the 7.4- and 7.65-MeV groups reported in 1H(24O,p′) (2012Ts03) and 9Be(26F,nX) (2011Ho05), respectively, are considered as separate states in this evaluation, since the former one was observed to decay by only one neutron emission to 23O, while the latter one by two sequential neutrons to 22O. Based on assigned configurations, the 7.4- and 7.6-MeV groups are tentatively assigned negative and positive parities, respectively. Additional study would be useful to determine if these states are same or different. In 24Na, 2014Fi01 (n, γ) proposed J π =(0,1,2)− for 4048.8 keV level based on weaker population from the capture state (J π =1+,2+) and mentioned to reexamine the J π =0+ assignment, suggested in earlier evaluations (1990En08, 2007Fi02). This evaluation includes the first observation of E0 transition, strength ρ 2(E0)=0.380 70 , for the 6432 keV transition from 0+ state at 6432 to 0+ g.s. in 24Mg reported in 2020Do10. Authors proposed the first-excited 0+ state of 24Mg to be superdeformed. In 24Al, the excited level energies deduced from (3He,t) measurements reported by different research groups vary significantly and it was not clear if some of those levels were same or different. Additional measurements are needed. [ABSTRACT FROM AUTHOR]

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Two methods of laser acceleration of protons/deuterons for initiation of nuclear reactions in the so-called pitcher-catcher scheme aimed at production of medical isotopes and obtaining short neutron pulses are studied using the combined particle-in-cell (PIC) and Monte Carlo (GEANT4) numerical simulation. It is demonstrated that the pulse repetition frequency on the order of 100 Hz is required for obtaining a medical dose of the radionuclids used in the positron-emission tomography (PET) in the case of ion acceleration from a thin foil most efficient in the forward direction by means of a femtosecond laser pulse with energy of several joules. In the case of ion acceleration from a low-density target most efficient in the transverse (radial) direction, lasers pulses of substantially higher energy and picosecond pulse duration have to be used, which allows one to increase the yield of radionuclids per unit deposited energy. In the process, the pulse repetition frequency must be at the level of 1–10 Hz. Laser generation of neutrons by means of reactions initiated by accelerated ions obtained using thin foils or targets of lower density is simulated, and the possibility of obtaining 108 neutrons per laser pulse using 3-J laser pulses is demonstrated. [ABSTRACT FROM AUTHOR]

Purposeful control of the physical properties of materials at the nanoscale is significant throughout the application. The most effective way for this is to change or replace the lattice atoms that make up the nanomaterial. In nanomaterials, the efficiency of the doping process will be high if individual lattice atoms are replaced at the atomic level without affecting neighbouring atoms. Here we show that, with the application of neutron transmutation technology (NTT), it is possible to perform targeted changes in nanoparticles (NPs) at the atomic scale. Similar experiments were carried out on different classes of NPs to explore the possible manipulation of the properties of nanomaterials using neutrons. During the experiments, nanocrystalline 3C–SiC, BN, B 4 C, Si and amorphous Si 3 N 4 and SiO 2 particles were modified by NTT. The possibility of nuclear reactions and neutron transmutation (NT) were investigated on the individual atoms, which are formed nanoparticles. As a result of NT, the changes in the physical properties of the listed NPs were explained by various spectroscopic approaches. Simultaneously, additional neutron effects, defects and structural changes on the surface of NPs were studied with microscopic imaging. [Display omitted] • With the application of NTT, it is possible to perform targeted changes in NPs at the atomic scale. • It has indicated that is possible to consciously control the properties of nanomaterials by NTT. • It is possible to change atoms by NT without changing the crystal structure in nanocrystalline particles. • Several spectroscopies revealed that NTT affect almost all physical parameters of nanoparticles. • It is possible to deliberately change the physical properties of nanomaterials with neutron flux. [ABSTRACT FROM AUTHOR]

The advantages of proton and light ion beam therapy compared to conventional photon radiation therapy are well-known, mainly thanks to the characteristic depth dose distribution of ions and their radio-biological effectiveness. Nevertheless, the use of ions implies different nuclear reactions that generate secondary particles, with neutrons among them. These secondary neutrons can travel far away from the treatment volume, their measurement is a challenging complex task, and their biological effects are particularly high for neutrons with energies in the MeV range. In this review, a comprehensive description of secondary neutron dosimetry in proton and light ion beam therapy is given. Many studies have been conducted on the quantification of the secondary neutron dose, most of them have been performed for proton beams, whereas for other ions like carbon, the available information is scarce. The main measurement campaigns are summarised, focusing on the type of detectors used. In line with the detectors' advantages and limitations, measurements performed inside and outside anthropomorphic phantoms are considered. The role of Monte Carlo radiation transport simulations is discussed since many experimental detection techniques need additional simulations to provide dose estimates. A focus on the current challenges for the measurements of neutrons with energies above 20 MeV is given, as this is one of the main components of secondary neutrons produced by therapeutic ion beams. Finally, the potential clinical relevance of the available and needed secondary neutron dose data is discussed, in terms of its impact on the treatment of patients. For this, the relative biological effectiveness of neutrons and the potential risk of cancer induction re-incidence or secondary cancer due to secondary neutron doses play a key role. • The relevance of studying secondary neutrons in ion therapy is presented. • Physical properties of secondary neutrons are described. • A summary of appropriate neutron detectors is given. • The phantoms used in different measurement campaigns are described. [ABSTRACT FROM AUTHOR]

The double-differential cross-sections, and neutron yields of the 9 Be ( 4 He , n) 12 C and 12 C (d , n) 13 N reactions at various energies, have been calculated. The cross-sections for the consider nuclear reactions were obtained using PHITS code based on Monte Carlo method. The calculated data were validated against the available experimental data with varying agreement up to 30 MeV. We have suggested the most suitable reaction, at certain energies, for better neutron yield and hence radiotherapy applications. • We calculated reaction and double differential cross sections using PHITS code. • We considered low - Z targets with scanty experimental cross-sections. • Neutron therapy by the 9 Be ( 4 He , n) 12 C and 12 C (d , n) 13 N reaction neutrons best at certain energies. • The 9 Be (d , n) 10 B neutron source preferred for radiotherapy across all energies. [ABSTRACT FROM AUTHOR]

The presence of a neutron halo in 15C has been demonstrated in several reaction experiments at intermediate energies. In the present study, the dynamical effects of this structure are observed for the first time at Coulomb barrier energies in the 15C + 208Pb quasi-elastic scattering at E lab = 65 MeV, measured at the HIE-ISOLDE facility, CERN using the high-granularity detector array GLORIA. A combined continuum discretised coupled channels and coupled reaction channels calculation describes the data well and significant coupling effects due both to breakup and single-neutron stripping are identified. [ABSTRACT FROM AUTHOR]

We investigate the contributions of various reaction channels to the interaction, reaction, charge-changing and neutron-changing cross sections. The goal is to investigate the relation between microscopic interactions and the symmetry energy component of the equation of state (EoS) of interest for the structure of neutron stars. We compare the neutron skins extracted from diverse experimental techniques with those obtained with Hartree–Fock–Bogoliubov calculations using 23 Skyrme and with eight density-dependent interactions used in the relativistic mean-field method. We show that no particular conclusion can be drawn on the best EoS in view of the wide range of uncertainty in the experimental data. We further investigate the prospects of using neutron-changing reactions to assess the isospin dependence of the neutron skin in neutron-rich nuclei. [ABSTRACT FROM AUTHOR]