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In radiation protection studies, the goal is to estimate the response of a detector exposed to a strongly attenuated radiation field. Monte Carlo (MC) particle transport codes give the possibility to efficiently solve for such responses using several variance-reduction (VR) methods that help allocating more CPU time to the simulation of highly contributing histories. The TRIPOLI-4® MC particle transport code offers two main methods, the exponential transform and adaptive multilevel splitting (AMS), which rely on the definition of a suitable importance map. In this paper, we present an implementation of a generalized Consistent Adjoint Driven Importance Sampling (CADIS) methodology for TRIPOLI-4. The implementation relies on coupling with the IDT code, a deterministic solver for the Boltzmann adjoint transport equation, for the generation of importance maps. We study the performance of both VR methods present in TRIPOLI-4 in this setting. In particular, to our knowledge, this is the first time that a CADIS-like methodology has been applied to AMS. [ABSTRACT FROM AUTHOR]

The specific boundary resistance, RB, of superconducting (S)/ferromagnetic (F) hybrids is obtained by measuring the dependence of the superconducting critical temperature, Tc, as a function of the thickness of the ferromagnetic layers, dF, and of the thickness of the superconducting layers, dS, in S/F bilayers and of the number of S/F bilayers, Nbil, for large values of Nbil, in F/[S/F]Nbil multilayers. We choose Nb for the superconducting material and two weakly ferromagnetic alloys, Cu0.38Ni0.62 and Pd0.81Ni0.19, for F. Analyzing the experimental results by using a matrix formulation of a theoretical model based on the Usadel equations, we are able to determine the value of RB which for both the S/F hybrids is of the order of 1 fΩm2. [ABSTRACT FROM AUTHOR]

The first harmonics of the magnetic response, of inter- and intragranular volume fractions of a FeSe0.5Te0.5 granular superconducting sample in an alternate magnetic field, have been numerically extracted from the measured magnetization of the whole system by using a model which considers the effects of the fundamental demagnetization fields generated by the magnetization itself. This allowed us to obtain the temperature and field behaviors of the inter- and intragranular ac losses during an ac cycle. These parameters have been found sensitive to the existence of the third harmonic components of the demagnetization field produced by the corresponding magnetization harmonics of the sample. This confirms that the effects of the magnetic response third harmonic components on the sample magnetization, through the demagnetization field, should be taken into account for a more detailed analysis of the measured ac magnetic curves. [ABSTRACT FROM AUTHOR]

The ferromagnetic transition temperature (Tc) of a weak ferromagnetic thin film Cu0.38Ni0.62 has been estimated by using an evolution of the Belov, Goriaga, and Arrott (BGA) model. In fact, the typically used measurements of the zero-field-cooled-field-cooled magnetic moment (m) as a function of temperature (T), the magnetic hysteresis loops (m(H)) as a function of field, and the temperature dependence of the remanent magnetic moment, performed on our sample, did not allow us to individuate precisely the value of Tc, mainly due to the influence of thermal effects and noise on the weak ferromagnetic response of the sample, resulting in a large uncertainty in the estimation of Tc. On the other hand, also the commonly used method of determining the Tc by means of a linear extrapolation of the high-field region of m2 as a function of the normalized magnetic field (H/m) at different temperatures (Arrott curves), working though for our analyzed material, could not completely fulfill the basic assumptions of the BGA model in general. For these reasons, we have considered the analysis of the derivatives of the Arrott curves, starting from observing that the Tc of the sample corresponds to the temperature where the curvature of the Arrott curves at low fields inverts. In this way, the sensitivity in the determination of the Curie point from the inductive measurements of the magnetic moment is improved while the correct assumptions of the Arrott model are also fully respected. [ABSTRACT FROM AUTHOR]

Monte Carlo calculations of fission of actinides and pre-actinides induced by protons and neutrons in the energy range from 100 MeV to 1 GeV are carried out by means of a recent version of the Liège Intranuclear Cascade Model, INCL++, coupled with two different evaporation-fission codes, GEMINI++ and ABLA07. In order to reproduce experimental fission cross sections, model parameters are usually adjusted on available ( p , f ) cross sections and used to predict ( n , f ) cross sections for the same isotopes. [ABSTRACT FROM AUTHOR]

The temperature dependent first and third harmonics of the AC magnetic susceptibility χ 1,3 ( T ) have been measured on Bi 4 O 4 S 3 . The χ 1 ( T ) magnetic response is due to the intergranular contribution with a transition temperature T c ≈ 4.4 K. The dependencies of the χ 3 ( T ) on the AC field amplitude and frequency reveal a critical state with the presence of the flux creep and the flux flow regimes. In fact, the field dependencies of the effective activation energy and of the frequency dependent critical current density have been found to be described with power laws characteristic of the collective creep regime involving large flux bundles. [ABSTRACT FROM AUTHOR]

Abstract: Particles and heavy ions are used in various fields of nuclear physics, medical physics, and material science, and their interactions with different media, including human tissue and critical organs, have therefore carefully been investigated both experimentally and theoretically since the 1930s. However, heavy-ion transport includes many complex processes and measurements for all possible systems, including critical organs, would be impractical or too expensive; e.g. direct measurements of dose equivalents to critical organs in humans cannot be performed. A reliable and accurate particle and heavy-ion transport code is therefore an essential tool in the design study of accelerator facilities as well as for other various applications. Recently, new applications have also arisen within transmutation and reactor science, space and medicine, especially radiotherapy, and several accelerator facilities are operating or planned for construction. Accurate knowledge of the physics of interaction of particles and heavy ions is also necessary for estimating radiation damage to equipment used on space vehicles, to calculate the transport of the heavy ions in the galactic cosmic ray (GCR) through the interstellar medium, and the evolution of the heavier elements after the Big Bang. Concerns about the biological effect of space radiation and space dosimetry are increasing rapidly due to the perspective of long-duration astronaut missions, both in relation to the International Space Station and to manned interplanetary missions in near future. Radiation protection studies for crews of international flights at high altitude have also received considerable attention in recent years. There is therefore a need to develop accurate and reliable particle and heavy-ion transport codes. To be able to calculate complex geometries, including production and transport of protons, neutrons, and alpha particles, 3-dimensional transport using Monte Carlo (MC) technique must be used. Today several particle and heavy-ion MC transport codes exist, e.g. Particle and Heavy-Ion Transport code System (PHITS), High Energy Transport Code-Human Exploration and Development of Space (HETC-HEDS), SHIELD-HIT, GEANT4, FLUKA, MARS, and MCNPX. In this paper, we present an extensive benchmarking of the calculated projectile fragmentation cross-sections from the reactions of 28Si, 40Ar, and 56Fe on polyethylene, carbon, aluminum, and copper targets (relevant to space radioprotection) using PHITS, FLUKA, HETC-HEDS, and MCNPX, against measurements. The influence of the different models used in the different transport codes on the calculated results is also discussed. Some measured cross-sections are also compared to the calculated cross-sections using NUCFRG2, which are incorporated in the 1-dimensional, deterministic radiation transport code HZETRN. [Copyright &y& Elsevier]

Abstract: Many new options have recently been included in PHITS, e.g., to calculate LET distributions of particles in matter or energy-deposition distributions event by event and correlations between energy depositions in different regions. This makes it possible to calculate the effects of particle radiation on biological and non-biological materials, e.g., risk for single event upsets in electronic devices. As a part of an extensive ongoing benchmarking of PHITS, we have compared calculated partial projectile fragmentation cross sections with accelerator-based measurements from the reactions of 200–1000MeV/n 4He, 12C, 14N, 16O, 20Ne, 28Si, 40Ar, and 56Fe on polyethylene, carbon, aluminum, copper, tin and lead, with different thicknesses, using different total reaction cross section models in PHITS. We have compared simulated and measured Bragg and attenuation curves of 200MeV/n 12C in water, and neutron energy spectra, at different angles, from 100 to 400MeV/n 12C stopped in water. Bragg curves for 110, 140, 170, 190 and 225MeV/n 3He in water have been studied, as well as gamma-ray dose decay curves of activated Cu target bombarded by 400 and 800MeV/n 40Ar. When using the default total reaction cross section model developed by Tripathi et al. (1996,1997 and 1999) [Tripathi, R.K., Cucinotta, F.A., Wilson, J.W. Accurate universal parameterization of absorption cross sections, Nucl. Instr. Methods B117, 347, 1996; Tripathi, R.K., Wilson, J.W., Cucinotta, F.A. Accurate universal parameterization of absorption cross sections II – neutron absorption cross sections. Nucl. Instr. Methods B129, 11, 1997 ; Tripathi, R.K., Cucinotta, F.A., Wilson, J.W. Accurate universal parameterization of absorption cross sections III – light systems. Nucl. Instr. Methods B155, 349, 1999.] the partial fragmentation cross sections appear to be systematically slightly underestimated by a factor which is independent on the fragment species within the same data set, and so do the simulated neutron energy spectra from selected heavy ion reactions; especially in the forward direction. The simulated attenuation and Bragg curves, however, show good agreement with measured ones. These observations stimulate further benchmarking to confirm the accuracy of the code and gives directions on possible improvements to be applied to the code in the near future. [Copyright &y& Elsevier]

Abstract: Shielding is the only countermeasure currently available for exposure to cosmic radiation during space travel. We compared aluminum (Al) and polymethylmethacrylate (PMMA, or lucite) shields of 20g/cm2 thickness using 1GeV protons accelerated at the NASA Space Radiation Laboratory. The dose rate increased after the shield, and the increase was more pronounced after the Al than the PMMA shield. No significant differences in the induction of chromosomal aberrations were observed in human lymphocytes exposed to the same dose with no shield or behind the Al and PMMA blocks. However, the biological effectiveness per incident proton was increased by the shields. Simulations using the General-Purpose Particle and Heavy-Ion Transport Code System (PHITS) show that the increase in dose is caused by target fragments, and aluminum produces more secondary protons than PMMA. Nevertheless, the spectrum of particles behind the shield is confined within the low-LET region, and the biological effectiveness is consequently similar. [Copyright &y& Elsevier]

Antiretroviral therapy (ART) significantly reduced Human Immunodeficiency Virus (HIV) morbidity and mortality; nevertheless, stigma still characterises the living with this condition. This study explored patients' coping experience by integrating narrative medicine (NM) in a non-interventional clinical trial. From June 2018 to September 2020 the study involved 18 centres across Italy; enrolled patients were both D/C/F/TAF naïve and previously ART-treated. Narratives were collected at enrolment (V1) and last visit (V4) and then independently analysed by three NM specialist researchers through content analysis. One-hundred and fourteen patients completed both V1 and V4 narratives. Supportive relationships with clinicians and undetectable viral load facilitated coping. Conversely, lack of disclosure of HIV-positive status, HIV metaphors, and unwillingness to narrate the life before the diagnosis indicated internalised stigma. This is the first non-interventional study to include narratives as patient reported outcomes (PROs). Improving HIV awareness and reducing the sense of guilt experienced by patients helps to overcome stigma and foster coping. [ABSTRACT FROM AUTHOR]

Antiretroviral therapy (ART) significantly reduced Human Immunodeficiency Virus (HIV) morbidity and mortality; nevertheless, stigma still characterises the living with this condition. This study explored patients’ coping experience by integrating narrative medicine (NM) in a non-interventional clinical trial. From June 2018 to September 2020 the study involved 18 centres across Italy; enrolled patients were both D/C/F/TAF naïve and previously ART-treated. Narratives were collected at enrolment (V1) and last visit (V4) and then independently analysed by three NM specialist researchers through content analysis. One-hundred and fourteen patients completed both V1 and V4 narratives. Supportive relationships with clinicians and undetectable viral load facilitated coping. Conversely, lack of disclosure of HIV-positive status, HIV metaphors, and unwillingness to narrate the life before the diagnosis indicated internalised stigma. This is the first non-interventional study to include narratives as patient reported outcomes (PROs). Improving HIV awareness and reducing the sense of guilt experienced by patients helps to overcome stigma and foster coping. [ABSTRACT FROM AUTHOR]

Abstract: The radiation environment in space is very different from the one encountered on Earth. In addition to the sparsely ionizing radiation, there are particles of different Z with energies ranging from keV up to hundreds of GeV which can cause severe damage to both electronics and humans. It is therefore important to understand the interactions of these highly ionizing particles with different materials such as the hull of space vehicles, human organs and electronics. We have used the Particle and Heavy-Ion Transport code System (PHITS), which is a three-dimensional Monte Carlo code able to calculate interactions and transport of particles and heavy ions with energies up to 100GeV/nucleon in most matter. PHITS is developed and maintained by a collaboration between RIST (Research Organization for Information Science & Technology), JAEA (Japan Atomic Energy Agency), KEK (High Energy Accelerator Research Organization), Japan and Chalmers University of Technology, Sweden. For the purpose of examining the applicability of PHITS to the shielding design we have simulated the ESA facility Matroshka (MTR) designed and lead by the German Aerospace Center (DLR). Preliminary results are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: We have collected from the literature partial charge-changing cross sections for projectiles with charge , energy ranging from 290 up to 2100 and interacting with several targets, in order to investigate weak and strong factorization properties. The same analysis methods as in our previous work have been applied to the data: we have shown that, except for hydrogen targets, weak and strong factorization properties are valid within 5%, thus confirming the results obtained in the first paper [C. La Tessa, et al., Test of weak and strong factorization in nucleus–nucleus collisions at several hundred , Nucl. Phys. A, in press]. Factorization parameters have been calculated and, in particular, target factors have been expressed with ad hoc analytical functions which describe the data trend very well. New expressions for weak and strong factorization properties can then be obtained by substituting the target factors with these functions: this formulation partially isolates the dependence of the partial charge-changing cross sections on the target and projectile mass numbers; moreover, fragment factors are the only parameters left in the formulas thus facilitating the future task of interpolating them with appropriate analytical expressions. [Copyright &y& Elsevier]

Abstract FISPACT-II is an advanced activation/transmutation and inventory code that employs the most up-to-date and sophisticated nuclear data forms, including the full TENDL-2017 library. TENDL includes residual nuclide production for incident particle energies up to 200 MeV. To address the needs of activation–transmutation simulation in incident-particle fields with energies up to and above 1 GeV, FISPACT-II has been extended to splice TENDL standard ENDF-6 nuclear data with extended nuclear data forms. Comparisons between JENDL-2007/HE, HEAD-2009, and the most recent intra-nuclear cascade models found within Geant4 led to an updated method for residual nuclide nuclear data production. This has been achieved with an automated INCL++/ABLA process that produces complete residual cross section format (MF=10) for activation/transmutation and inventory calculations. The current High-Energy Intra-Nuclear Cascade Liège-based Residual (HEIR-0.1) library includes proton-induced cross sections up to 1 GeV for 2095 targets. These data are available with the most recent release 4.0 of FISPACT-II. [ABSTRACT FROM AUTHOR]

We report the experimental method of the evaluation of the specific boundary resistance, R, of superconductor (S)/non-superconductor (NS) interfaces by measuring the superconducting critical temperature, T, as a function of the thickness of the superconducting layer, d, in S/NS hybrids and of the number of S/NS bilayers, N, for a large number of N in NS/[S/NS] $_{N_{\mathrm{bl}}}$ multilayers. Two types of systems have been studied. We choose Nb as the S material for both types and Cu for a normal metal (N) for the first one. In the second case, a weakly ferromagnetic alloy (F), CuNi, was chosen for NS. Analyzing the experimental results by solving exactly the Usadel equations, we were able to unambiguously determine the value of R for both the S/N and S/F hybrids. The results show that Nb/Cu is characterized by a lower value of the interfacial specific resistance with respect to the case of Nb/CuNi. [ABSTRACT FROM AUTHOR]

The paper presents the measured cumulative yields of 44 Ti for nat Cr, 56 Fe, nat Ni and 93 Nb samples irradiated by protons at the energy range 0.04–2.6 GeV. The obtained excitation functions are compared with calculations of the well-known codes: ISABEL, Bertini, INCL4.2+ABLA, INCL4.5+ABLA07, PHITS, CASCADE07 and CEM03.02. The predictive power of these codes regarding the studied nuclides is analyzed. [ABSTRACT FROM AUTHOR]

Abstract: A new approach to describing neutron spectra of deuteron-induced reactions in the Monte Carlo simulation for particle transport has been developed by combining the Intra-Nuclear Cascade of Liège (INCL) and the Distorted Wave Born Approximation (DWBA) calculation. We incorporated this combined method into the Particle and Heavy Ion Transport code System (PHITS) and applied it to estimate spectra on natLi, 9Be, and natC targets at incident energies ranging from 10 to 40MeV. Double differential cross sections obtained by INCL and DWBA successfully reproduced broad peaks and discrete peaks, respectively, at the same energies as those observed in experimental data. Furthermore, an excellent agreement was observed between experimental data and PHITS-derived results using the combined method in thick target neutron yields over a wide range of neutron emission angles in the reactions. We also applied the new method to estimate spectra in the reactions, and discussed the validity for the proton emission spectra. [Copyright &y& Elsevier]

Total fission cross sections of 18Ta induced by protons at different relativistic energies have been measured at GSI Darmstadt using the inverse kinematic technique. These data contribute to solve inconsistencies in previously reported measurements, but also help to benchmark state-of-the-art reaction codes. The energy range covered with these measurements allowed us to investigate the onset and temperature dependence of dissipative and transient effects at small deformation. [ABSTRACT FROM AUTHOR]

Inclusive multineutron and multiproton removal cross sections from 112Sn and 104Sn at relativistic energies have been measured. The data show two distinct regimes of the reaction process that depend on the nucléon evaporation cost of the final nucleus. This behavior is universal by regarding the mass or asymmetry of the initial system or target composition. A state-of-the-art cascade and deexcitation model reproduces the observed trend but systematically fails in reproducing cross sections for the removal of the more bound nucléon species. [ABSTRACT FROM AUTHOR]

Astatine isotopes can be produced in liquid lead-bismuth eutectic targets through proton-induced double charge exchange reactions on bismuth or in secondary helium-induced interactions. Models implemented into the most common high-energy transport codes generally have difficulties to correctly estimate their production yields as was shown recently by the ISOLDE Collaboration, which measured release rates from a lead-bismuth target irradiated by 1.4 and 1 GeV protons. In this paper, we first study the capability of the new version of the Liège intranuclear cascade model, INCL4.6, coupled to the deexcitation code ABLA07 to predict the different elementary reactions involved in the production of such isotopes through a detailed comparison of the model with the available experimental data from the literature. Although a few remaining deficiencies are identified, very satisfactory results are found, thanks in particular to improvements brought recently on the treatment of low-energy helium-induced reactions. The implementation of the models into MCNPX allows identifying the respective contributions of the different possible reaction channels in the ISOLDE case. Finally, the full simulation of the ISOLDE experiment is performed, taking into account the likely rather long diffusion time from the target, and compared with the measured diffusion rates for the different astatine isotopes, at the two studied energies, 1.4 and 1 GeV. The shape of the isotopic distribution is perfectly reproduced as well as the absolute release rates, assuming in the calculation a diffusion time between 5 and 10hours. This work finally shows that our model, thanks to the attention paid to the emission of high-energy clusters and to low-energy cluster induced reactions, can be safely used within MCNPX to predict isotopes with a charge larger than that of the target by two units in spallation targets, and, probably, more generally to isotopes created in secondary reactions induced by composite particles. [ABSTRACT FROM AUTHOR]

The new version (INCL4.6) of the Liège intranuclear cascade (INC) model for the description of spallation reactions is presented in detail. Compared to the standard version (INCL4.2), it incorporates several new features, the most important of which are: (i) the inclusion of cluster production through a dynamical phase space coalescence model, (ii) the Coulomb deflection for entering and outgoing charged particles, (iii) the improvement of the treatment of Pauli blocking and of soft collisions, (iv) the introduction of experimental threshold values for the emission of particles, (v) the improvement of pion dynamics, (vi) a detailed procedure for the treatment of light-cluster-induced reactions taking care of the effects of binding energy of the nucléons inside the incident cluster and of the possible fusion reaction at low energy. Performances of the new model concerning nucleon-induced reactions are illustrated by a comparison with experimental data covering total reaction cross sections, neutron, proton, pion, and composite double-differential cross-sections, neutron multiplicities, residue mass and charge distributions, and residue recoil velocity distributions. Whenever necessary, the INCL4.6 model is coupled to the ABLA07 de-excitation model and the respective merits of the two models are then tentatively disentangled. Good agreement is generally obtained in the 200 MeV to 2 GeV range. Below 200 MeV and down to a few tens of MeV, the total reaction cross section is well reproduced and differential cross sections are reasonably well described. The model is also tested for light-ion induced reactions at low energy, below 100 MeV incident energy per nucleón. Beyond presenting the update of the INCL4.2 model, attention has been paid to applications of the new model to three topics for which some particular aspects are discussed for the first time. The first topic is the production of clusters heavier than alpha particle. It is shown that the energy spectra of these produced clusters are consistent with coalescence. The second topic regards the longitudinal residue recoil velocity and its fluctuations. Excellent results are obtained for these quantities. It addition, it is shown that the distributions of these quantities display typical random-walk characteristics, at least for not-too-large mass losses. They are interpreted as a direct consequence of the independence of successive binary collisions occurring during the cascade process. The last topic concerns the total reaction cross section and the residue-production cross sections for low-energy incident light ions. It is shown that our new model can give a rather satisfactory account of these cross sections, offering so an alternative to fusion models and the advantage of a single model for the progressive change from fusion to pre-equilibrium mechanisms. [ABSTRACT FROM AUTHOR]

Nuclide production cross sections measured at the Institute for Theoretical and Experimental Physics (ITEP) for the targets of natCr, 55Fe, natNi, 93Nb, 18lTa, natW, natPb, and 209Bi irradiated by protons with energies from 40 to 2600 MeV were used to estimate the predictive accuracy of several popular high-energy transport codes. A general agreement of the ITEP data with the data obtained by other groups, including the numerous GSI data measured by the inverse kinematics method was found. Simulations of the measured data were performed with the MCNPX (BERTINI and ISABEL options), CEM03.02, INCL4.2 + ABLA, INCL4.5 + ABLA07, PHITS, and CASCADE.07 codes. Deviation factors between the calculated and experimental cross sections have been estimated for each target and for the whole energy range covered by our measurements. Two-dimensional diagrams of deviation factor values were produced for estimating the predictive power of every code for intermediate, not measured masses of nuclei targets and bombarding energies of protons. Further improvements of all tested here codes are recommended. In addition, new measurements at ITEP of nuclide yields from the 208Pb target irradiated by 500-MeV protons are presented. A good agreement between these new data and the GSI measurements obtained by the inverse kinematics method was found. [ABSTRACT FROM AUTHOR]

The dose reduction rates brought about by the installation of additional water shielding in a spacecraft are calculated in the paper using the particles and heavy ion transport code system PHITS, which can deal with transport of all kinds of hadrons and heavy ions with energies up to 100 GeV/n in three-dimensional phase spaces. In the PHITS simulation, an imaginary spacecraft was irradiated isotropically by cosmic rays with charges up to 28 and energies up to 100 GeV/n, and the dose reduction rates due to water shielding were evaluated for 5 types of doses: the dose equivalents obtained from the LET and linear energy spectra, the dose equivalents to skin and red bone marrow, and the effective dose equivalent. The results of the simulation indicate that the dose reduction rates differ according to the type of dose evaluated. For example, 5 g/cm water shielding reduces the effective dose equivalent and the LET dose equivalent by approximately 14% and 32%, respectively. Such degrees of dose reduction can be regarded to make water shielding worth the efforts required to install it. [ABSTRACT FROM AUTHOR]

Abstract: Radiation hazard for space missions is mainly due to cosmic ray protons, helium nuclei and light ions, whose energy spectrum is maximum around 1GeV per nucleon but remains non-negligible for energies up to 15GeV per nucleon. Nuclear reactions induced by high energy protons are often described by intranuclear cascade plus evaporation models. The attention is focused here on the Liège Intranuclear Cascade model (INCL), which has been shown to reproduce fairly well a great deal of experimental data for nucleon-induced reactions in the 200MeV to 2GeV range, when coupled with the ABLA evaporation-fission code. In order to extend the model to other conditions relevant for space radiation, three improvements of INCL are under development. They are reported on here. First, the reaction model has been extended to nucleon–nucleus reactions at incident energies up to 15GeV, mainly by the inclusion of additional pion production channels in nucleon–nucleon collisions during the cascade. Second, a coalescence mechanism for the emission of light charged particles has been implemented recently. Finally, the model has been modified in order to accommodate light ions as projectiles. First results are shown and compared with illustrative experimental data. Implications for issues concerning radiation protection in space are discussed. [Copyright &y& Elsevier]

The cross sections for nuclide production in thin Fe and Cr targets irradiated by 0.04-2.6-GeV protons are measured by direct γ spectrometry using two γ spectrometers with the resolutions of 1.8 and 1.7 keV for the Co 1332-keV γ line. As a result, 649 yields of radioactive residual product nuclei have been obtained. The Al( p, x)Na reaction has been used as a monitor reaction. The experimental data are compared with the MCNPX (BERTINI, ISABEL), CEM03.02, INCL4.2, INCL4.5, PHITS, and CASCADE07 calculations. [ABSTRACT FROM AUTHOR]

The cross sections for nuclide production in thin Wand Ta targets irradiated by 0.04-2.6-GeV protons have been measured by direct γ spectrometry using two γ spectrometers with the resolutions of 1.8 and 1.7 keV in the Co 1332-keV γ line. As a result, 1895 yields of radioactive residual product nuclei have been obtained. The Al( p, x)Na reaction has been used as a monitor reaction. The experimental data have been compared with the MCNPX (BERTINI, ISABEL), CEM03.02, INCL4.2, INCL4.5, PHITS, and CASCADE07 calculations. [ABSTRACT FROM AUTHOR]

The cross sections for nuclide production in thin Nb and Ni targets irradiated by 0.04- to 2.6-GeV protons have been measured by direct γ spectrometry using two γ spectrometers with the resolutions of 1.8 and 1.7 keV in the Co 1332-keV γ line. As a result, 1112 yields of radioactive residual nuclei have been obtained. The Al( p, x)Na reaction has been used as a monitor reaction. The experimental data have been compared with the MCNPX (BERTINI, ISABEL), CEM03.02, INCL4.2, INCL4.5, PHITS, and CASCADE07 calculations. [ABSTRACT FROM AUTHOR]

The cross sections for the production of Gd in W and Ta targets irradiated by 0.4-, 0.6-, 0.8-, 1.2-, 1.6-, and 2.6-GeV protons at the ITEP accelerator complex have been measured by direct α spectrometry without chemical separation. The experimental data have been compared with the data obtained at other laboratories and with the theoretical simulations of the yields on the basis of the BERTINI, ISABEL, CEM03.02, INCL4.2, INCL4.5, CASCADE07, and PHITS codes. [ABSTRACT FROM AUTHOR]

Abstract: PHITS (Particle and Heavy-Ion Transport code System) is a general-purpose three-dimensional Monte Carlo code, developed and maintained by RIST, JAEA and KEK in Japan together with Sihver et al. at Chalmers in Sweden. PHITS can deal with the transports of all varieties of hadrons and heavy ions with energies up to around 100GeV/nucleon, and in this paper the current status of PHITS is presented. We introduce a relativistically covariant version of JQMD, called R-JQMD, that features an improved ground state initialization algorithm, and we will present the introduction of electron and photon transport in PHITS using EGS5, which have increased the energy region for the photon and energy transport from up to around 3GeV to up to several hundred GeV depending on the atomic number of the target. We show how the accuracy in dose and fluence calculations can be improved by using tabulated cross sections. Benchmarking of shielding and irradiation effects of high energy protons in different materials relevant for shielding of accelerator facilities is also presented. In particular, we show that PHITS can be used for estimating the dose received by aircrews and personnel in space. In recent years, many countries have issued regulations or recommendations to set annual dose limitations for aircrews. Since estimation of cosmic-ray spectra in the atmosphere is an essential issue for the evaluation of aviation doses, we have calculated these spectra using PHITS. The accuracy of the atmospheric propagation simulation of cosmic-ray performed by PHITS has been well verified by experimental cosmic-ray spectra taken under various conditions. Based on a comprehensive analysis of the simulation results, an analytical model called “PARMA” has been proposed for instantaneously estimating the atmospheric cosmic-ray spectra below the altitude of 20km. We have also performed preliminary simulations of long-term dose distribution measurements at the ISS performed with the joint ESA-FSA experiment MATROSHKA-R (MTR-R) led by the Russian Federation Institute of Biomedical Problems (IMBP) and the ESA supported experiment MATROSHKA (MTR), led by the German Aerospace Center (DLR). For the purpose of examining the applicability of PHITS to the shielding design in space, the absorbed doses in a tissue equivalent water phantom inside an imaginary space vessel has been estimated for different shielding materials of different thicknesses. The results confirm previous results which indicate that PHITS is a suitable tool when performing shielding design studies of spacecrafts. [Copyright &y& Elsevier]

Abstract: Reliable predictions of light charged particle production in spallation reactions are important to correctly assess gas production in spallation targets. In particular, the helium production yield is important for assessing damage in the window separating the accelerator vacuum from a spallation target, and tritium is a major contributor to the target radioactivity. Up to now, the models available in the MCNPX transport code, including the widely used default option Bertini–Dresner and the INCL4.2–ABLA combination of models, were not able to correctly predict light charged particle yields. The work done recently on both the intranuclear cascade model INCL4, in which cluster emission through a coalescence process has been introduced, and on the de-excitation model ABLA allows correcting these deficiencies. This paper shows that the coalescence emission plays an important role in the tritium and production and that the combination of the newly developed versions of the codes, INCL4.5–ABLA07, now lead to good predictions of both helium and tritium cross-sections over a wide incident energy range. Comparisons with other available models are also presented. [Copyright &y& Elsevier]

Abstract: The ALTEA-Space detector has been calibrated by testing its response to several monochromatic beams. These measurements provided energy-deposition spectra in silicon of 100, 600 and 1000MeV/nucleon 12C and 200 and 600MeV/nucleon 48Ti. The results have been compared to three Monte Carlo transport codes, namely PHITS, GEANT4 and FLUKA. Median, full width at half maximum (FWHM) and interquartile range (IQR) have been calculated for all datasets to characterize location, width and asymmetry of the energy-deposition spectra. Particular attention has been devoted to the influence of δ rays on the shape of the energy-deposition spectrum, both with the help of analytical calculations and Monte Carlo simulations. The two approaches proved that, in this range of projectile charge, projectile energy and detector size, the leakage of secondary electrons might introduce a difference between the energy-loss and energy-deposition spectrum, in particular by changing the location, width and symmetry of the distribution. The overall agreement between the Monte Carlo predictions and the measurements is fair and makes PHITS, FLUKA and GEANT4 all possible candidates for simulating ALTEA-Space experiment. [Copyright &y& Elsevier]

Abstract: We present measurements and model calculations of fluence and linear energy transfer in water () obtained using 56Fe beams with 1GeV/amu kinetic energy incident on aluminum, polyethylene, PMMA, and lead targets. The measured spectra are compared to predictions of the PHITS model. The study is motivated by NASA''s need to develop accurate heavy ion transport codes to assess radiation exposures in deep space, where galactic cosmic rays are important. The data were obtained at the Alternating Gradient Synchrotron at the Brookhaven National Laboratory. Distributions of charge and LET depend on the depth and composition of the target. Several of the targets studied are “thick”, defined operationally as a depth that presents at least 50% of an interaction length to the beam ions. In a thick target, the probability of a secondary interaction is significant, tertiary interactions can also be important, and the target-exit fluence and charge distributions depend on unmeasured cross sections that can only be estimated by nuclear interaction models. Comparisons between calculated and measured spectra are therefore of considerable interest. Some targets used in the study are thin, so that secondary and higher interaction probabilities are negligible, allowing more stringent comparisons between the data and the model. We find that PHITS reproduces some aspects of the experimental data well, but fails to accurately reproduce many of the measured fragment fluences. [Copyright &y& Elsevier]

Abstract: Projectile total and partial charge-changing cross sections have been measured for argon ions at 400 MeV/nucleon in carbon, aluminum, copper, tin and lead targets; cross sections for hydrogen were also obtained using a polyethylene target. The validity of weak and strong factorization properties has been investigated for partial charge-changing cross sections; measurements obtained for carbon, neon and silicon beams at 290 and 400 MeV/nucleon and iron beam at 400 MeV/nucleon, in carbon, aluminum, copper, tin and lead targets have also been used for the test. Two different analysis methods were applied and both indicated that these properties are valid, without any significant difference between weak and strong factorization. The factorization parameters have then been calculated and analyzed in order to find some systematic behavior useful for modeling purposes. [Copyright &y& Elsevier]