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The capabilities of the new version of the Li\`ege intranuclear cascade model (labeled $\mathrm{INCL}++6$ from now on) are presented in detail. This new version of INCL is able to handle strange particles, such as kaons and the $\mathrm{\ensuremath{\Lambda}}$ and $\mathrm{\ensuremath{\Sigma}}$ hyperons, and the associated reactions and also allows extending nucleon-nucleon collisions up to about $15\text{--}20$ GeV incident energy. Compared to the previous version, new observables can be studied, e.g., kaon, hyperon, and hypernuclei production cross sections (with the use of a suitable de-excitation code) as well as aspects of kaon-induced spallation reactions. The main purpose of this paper is to present the specific ingredients of the new INCL version and its new features, notably the newly implemented variance reduction scheme. We also compare, for some illustrative strangeness production cases, theoretical results calculated using this version of INCL with experimental data.

Motivated by a renewed interest in studies of hypernuclei, the strangeness degree of freedom was implemented in the intranuclear cascade model INCL. This model takes care of the first stage of reactions between a nucleon (or a light cluster) and a nucleus at energies from a few tens of MeV up to a few GeV. After emission of fast particles, a hot remnant nucleus is produced and another model, combined to INCL, handles the de-excitation (Abla in our case). The main ingredients are discussed and we compare the results to experimental data.

The recent developments of the Liège intranuclear cascade model INCL are reviewed. The INCL4.6 version of this model was able when coupled with the ABLA07 de-excitation code, to describe rather well a huge set of experimental data in an incident energy range spanning between 200 MeV and 3 GeV, as it has been testified by an intercomparison of spallation codes organized by the IAEA. Since that time, the model has been implemented in several nuclear particle transport codes. Therefore, the possible applications of INCL have been enlarged to focus on diverse fields, and in the recent years, the model has been further developed to be applicable to these new issues and also to cope with remaining deficiencies. The new features include: i) a sophisticated dynamical model for light cluster emission (up to O ions), ii) the accommodation of light nuclei as projectiles, iii) a new procedure to take account of the fuzziness of the Fermi surface, and iv) an extension of the model to higher energy. The aim of this contribution is to present for the first time and to discuss the physics of the added features, and to give a hint about the performances of the new model.

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.

International audience; The reactions$^{136}$Xe + p and$^{136}$Xe +$^{12}$C have been studied in inverse kinematics at 1 A GeV with the SPALADiN setup at GSI. The detection in coincidence of the final-state charged particles (projectile residues, nuclei of charge $ Z \geq 2$ and neutrons was performed with a big-aperture dipole magnet and large-acceptance detectors. This provided an extended coverage of the phase space of decay products of the prefragment formed at the end of the intranuclear cascade. This coincidence measurement, performed on an event-by-event basis permits both an estimate of the excitation energy of the prefragments and a determination of their deexcitation channels. The element production cross sections are compared with existing data and theoretical models. The evolution of observables such as the total multiplicity or the fragment production with the prefragment’s excitation energy is studied for both reactions and compared with models.

The intranuclear cascade model INCL (Li\`ege Intranuclear Cascade) is now able to simulate spallation reactions induced by projectiles with energies up to roughly 15 GeV. This was made possible thanks to the implementation of multipion emission in the NN, $\Delta$N and $\pi$N interactions. The results obtained with reactions on nuclei induced by nucleons or pions gave confidence in the model. A next step will be the addition of the strange particles, $\Lambda$, $\Sigma$ and Kaons, in order to not only refine the high-energy modeling, but also to extend the capabilities of INCL, as studying hypernucleus physics. Between those two versions of the code, the possibility to treat the $\eta$ and $\omega$ mesons in INCL has been performed and this is the topic of this paper. Production yields of these mesons increase with energy and it is interesting to test their roles at higher energies. More specifically, studies of $\eta$ rare decays benefit from accurate simulations of its production. These are the two reasons for their implementation. Ingredients of the model, like elementary reaction cross sections, are discussed and comparisons with experimental data are carried out to test the reliability of those particle productions., Comment: 22 pages, 17 figures, submitted to EPJ Plus

International audience; Motivated by a renewed interest in studies of hypernuclei, the strangeness degree of freedom was implemented in the intranuclear cascade model INCL. This model takes care of the first stage of reactions between a nucleon (or a light cluster) and a nucleus at energies from a few tens of MeV up to a few GeV. After emission of fast particles, a hot remnant nucleus is produced and another model, combined to INCL, handles the de-excitation (the Abla model in our case). The main ingredients will be discussed and we will compare the results to experimental data. The experimental kaon spectra for different target elements and at different energies agree reasonable well with the model predictions. The main remaining discrepancies are analysed and will be explained.

International audience; The production of strange particles (kaons, hyperons) and hypernuclei in light charged-particle-induced reactions in the energy range of a few GeV (2-15 GeV) has become a topic of active research in several facilities (e.g., HypHI and PANDA at GSI and/or FAIR (Germany), JLab (USA), and JPARC (Japan)). This energy range represents the low-energy limit of the string models (degree of freedom: quark and gluon) or the high-energy limit of the so-called spallation models (degree of freedom: hadrons). A well-known spallation model is INCL, the Liège intranuclear cascade model (combined with a de-excitation model to complete the reaction). INCL, known to give good results up to 2-3GeV, was recently upgraded by the implementation of multiple pion emission to extend the energy range of applicability up to roughly 15GeV. The next step, to account also for strange particle production, both for refining the high-energy domain and making it usable when strangeness appears, requires the following main ingredients: i) the relevant elementary cross sections (production, scattering, and absorption) and ii) the characteristics of the associated final states. Some of those ingredients are already known and, sometimes, already used in models of the same type (e.g., Bertini, GiBUU), but this paper aims at reviewing the situation by compiling, updating, and comparing the necessary elementary information which are independent of the model used.

The new version of the Li\`ege intranuclear-cascade model (INCL), recently extended to the production of strange particles and hypernuclei, is used to investigate the $\mathrm{\ensuremath{\Lambda}}$-nucleus potential in a broad range of nuclear masses from Si to Pb. The combination of the INCL calculation results with experimental cross sections of $\mathrm{\ensuremath{\Lambda}}$ hypernuclei, obtained from (${\ensuremath{\pi}}^{+},{K}^{+}$) reaction studies, allows us to constrain the $\mathrm{\ensuremath{\Lambda}}$-nucleus potential depth with an accuracy of about 0.9 MeV. Our results show that the potential depth increases with the mass number ($A$) from 28 MeV in the region of medium-mass hypernuclei up to a maximum of 39.6 MeV in the region of heavy hypernuclei around $A=208$. This deviation could be related to the nucleon-isospin dependence of the three-body $\mathrm{\ensuremath{\Lambda}}$-nucleon-nucleon force in asymmetry matter whose contribution is more relevant in hyperneutron matter due to a strong contribution from $\mathrm{\ensuremath{\Lambda}}nn$ interactions.

International audience; The Liège intranuclear-cascade model (INCL) has been improved using a refined description of the matter and energy densities in the nuclear surface. Hartree-Fock-Bogoliubov calculations with the Skyrme interaction were used to obtain a more realistic description of the proton and neutron density profiles. We find that the new approach, together with a realistic modeling of the de-excitation process of the nuclear pre-fragments, improves the description of the production cross sections of the heaviest nuclear residues produced by charge-exchange processes in spallation reactions, where the excitation of baryonic resonances plays an important role.

We proposed a new nuclear reaction model in combination of Intra-Nuclear Cascade of Liege (INCL) and the Distorted Wave Born Approximation (DWBA) calculation, and incorporated it into the Particle and Heavy Ion Transport code System (PHITS). This model was applied to deuteron induced reactions on nat Li and 9 Be targets for deuteron incident energies of 40 and 18 MeV, respectively. Double-differential cross sections and neutron yields on thick targets obtained by PHITS using the model reproduce experimental data quite well.

International audience; The prediction of one-nucleon-removal cross sections by the Liège intranuclear-cascade model has been improved using a refined description of the matter and energy densities in the nuclear surface. Hartree-Fock-Bogoliubov calculations with the Skyrme interaction are used to obtain a more realistic description of the radial-density distributions of protons and neutrons, as well as the excitation-energy uncorrelation at the nuclear surface due to quantum effects and short-range correlations. The results are compared with experimental data covering a large range of nuclei, from carbon to uranium, and projectile kinetic energies. We find that the new approach is in good agreement with experimental data of one-nucleon-removal cross sections covering a broad range in nuclei and energies. The new ingredients also improve the description of total reaction cross sections induced by protons at low energies, the production cross sections of heaviest residues close to the projectile, and the triple-differential cross sections for one-proton removal. However, other observables such as quadruple-differential cross sections of coincident protons do not present any sizable sensitivity to the new approach. Finally, the model is also tested for light-ion-induced reactions. It is shown that the new parameters can give a reasonable description of the nucleus-nucleus total reaction cross sections at high energies.

We use particle-transport simulations to show that secondary pions play a crucial role for the development of the hadronic cascade and therefore for the production of neutrons and photons from thick spallation targets. In particular, for the n_TOF lead spallation target, irradiated with 20 GeV/c protons, neutral pions are involved in the production of ~90% of the high-energy photons; charged pions participate in ~40% of the integral neutron yield. Nevertheless, photon and neutron yields are shown to be relatively insensitive to large changes of the average pion multiplicity in the individual spallation reactions. We characterize this robustness as a peculiar property of hadronic cascades in thick targets., Comment: 17 pages, 14 figures. Submitted to Eur. Phys. J. A

Spallation reactions play an important role in many branches of physics. If the nuclear reaction induced by low energy neutrons as in nuclear power plants or research reactors can be based on cross section database, it is not the case for spallation reactions due to the energy range, from 100 MeV up to ~3 GeV, and to the candidate targets (all nuclei). Then these reactions have to be modeled. Developments of codes are linked to new experiment and this ex-plains why fifteen years ago a first benchmark has been launched, restricted to particle production, followed by a second one on residues. Since then new data have been measured and computer tools are improved day after day, so a new benchmark has been organized, under the auspices of the IAEA, taken into account all types of results, particle and residue production, with a possibility to update the data (experimental and code calculation) via a web site. Re-sults of the benchmark concerning both the analysis of the prediction capabilities of the seventeen model-participants and the first conclusions on the physics of spallation models are presented.

The composition of the space radiation environment inside spacecrafts is modified by the interaction with shielding material, with equipment and even with the astronauts' bodies. Accurate quantitative estimates of the effects of nuclear reactions are necessary, for example, for dose estimation and prediction of single-event-upset rates. To this end, it is necessary to construct predictive models for nuclear reactions, which usually consist of an intranuclear-cascade or quantum-molecular-dynamics stage, followed by a nuclear-de-excitation stage. While it is generally acknowledged that it is necessary to accurately simulate the first reaction stage, transport-code users often neglect or underestimate the importance of the choice of the de-excitation code. The purpose of this work is to prove that the de-excitation model is in fact a non-negligible source of uncertainty for the prediction of several observables of crucial importance for space applications. For some particular observables, the systematic uncertainty due to the de-excitation model actually dominates the total uncertainty. Our point will be illustrated by making use of nucleon-nucleus calculations performed with several intranuclear-cascade/de-excitation models, such as the Li\`{e}ge Intranuclear Cascade model (INCL) and Isabel (for the cascade part) and ABLA07, Dresner, GEM, GEMINI++ and SMM (on the de-excitation side)., Comment: 12 pages, 6 figures. Presented at the 38th COSPAR Scientific Assembly (Bremen, Germany, 18-25 July 2010). Submitted to Advances in Space Research

INCL (Liege IntraNuclear Cascade model) combined with a deexcitation code has been used a lot for numerous simulations of spallation reactions during the last two decades. We go back over some of those simulations to address the capabilities of such codes and to show some improvements. The four examples of simultation are: the EURISOL project, the MEGAPIE target, the ESS facility, and the cosmogenic nuclide production. The goal is to discuss respectively designing and optimisation, predictive power and reliability, feasibility and uncertainty estimate, and the use of modeling to mitigate lack of experimental data.

The intranuclear cascade model INCL4 has been shown to be very successful for describing, without adjustable parameters, a whole set of data for p-induced reactions in the 40 MeV–2 GeV energy range. In view of its possible application to cosmic ray interactions, the INCL4 code has been extended to the 2–15 GeV energy range, so covering a large part of the spectrum of the incident energy of the cosmic rays. In this paper, the changes brought into the INCL4 code are discussed and some illustrative comparisons between the results given by the modified version of the code and experimental data are presented.

The MEGAPIE project aimed to design, build and operate a liquid metal spallation neutron target of about 1 MW beam power in the SINQ facility at the Paul Scherrer Institut (Villigen, Switzerland). This project is an important step in the roadmap towards the demonstration of the accelerator driven system (ADS) concept and high power liquid metal targets in general. Following the design phase, an experimental program was defined to provide a complete characterization of the facility by performing a “mapping” of the neutron flux at different points, from the center of the target to the beam lines. The neutronic performance of the target was studied using different experimental techniques with the goals of validating the Monte Carlo codes used in the design of the target; additionally, the performance was compared with the solid lead targets used before and after the MEGAPIE experiment.

International audience; This article focuses on spallation reactions, i.e. interactions of energetic nucleons, basically with a kinetic energy in the 100 MeV to a few GeV range, with a target nucleus. These processes are described rather successfully by the so-called Intranuclear Cascade (INC) plus evaporation models. They can be viewed as a first stage of nucleon-nucleon collisions, ejecting fast particles, followed by evaporation of slow particles from the target remnant. These cascade + evaporation models have, now, globally reached a high level of predictive power, owing in particular to successive research programs. The present work, which is an outcome of one of these programs, the recent European Union ANDES research program, deals with a set of reactions (or observable quantities), which can be due to a single collision, such as the one-nucleon removal reactions or the quasi-elastic elastic process. A survey of the experimental data is presented, which allows to clearly point out that, often, the INC models are unsatisfactory for the description of these peculiar events, whereas they are rather successful for the rest of the experimental data. This paradoxical situation is tentatively related to quasi-particle effects which are neglected in INC models.

We assess the suitability of nuclear-reaction codes for the generation of accurate cross-section libraries targeted at the simulation of the transport of high-energy protons (up to 250 MeV) in the human body, or in any material containing light nuclides. To this end we present an extensive study of elastic, reaction and fragmentation cross sections for proton-induced reactions on several nuclides. We compare TALYS evaluations against experimental data and, wherever applicable, against the predictions of the INCL/ABLA07 nuclear-reaction model. The TALYS evaluations have been cast in the form of a new cross-section library, which also includes evaluated proton-proton cross sections based on the NN-OnLine tool.

International audience; It is a well-established fact that intranuclear-cascade models generally overestimate the cross sections for one-proton removal from heavy, stable nuclei by a high-energy proton beam, but they yield reasonable predictions for one-neutron removal from the same nuclei and for one-nucleon removal from light targets. We use simple shell-model calculations to investigate the reasons for this deficiency. We find that a refined description of the neutron skin and of the energy density in the nuclear surface is crucial for the aforementioned observables, and that neither ingredient is sufficient if taken separately. As a by-product, the predictions for removal of several nucleons are also improved by the refined treatment.

The state-of-the-art regarding the predicting capabilities of some of the physics models available in MCNPX for Accelerator-Driven System design is discussed. The identified remaining deficiencies, which originate either from a lack of experimental data or from not well understood physics mechanisms, are stressed. To solve these problems, more constraining experiments are now needed to allow a deeper understanding of the reaction mechanisms.

New improvements of the INCL4 cascade model, bearing on cluster production, nucleon and pion potentials and Pauli blocking at low energy, are reviewed.

A model is proposed to describe emission of light charged clusters during the cascade stage in nucleon-induced spallation reactions. It consists in implementing a surface percolation procedure into the Liege intranuclear cascade (INCL4) model: when a nucleon is ready to leave the nuclear surface, it is allowed to drag along a cluster of nucleons, under some conditions of closeness in phase space. This possibility relies on the instantaneous dynamical phase space occupancy in the nuclear surface. The following clusters are considered: d,t, 3 He , 4 He . Good agreement is obtained with experimental data relative to heavy and medium-heavy targets at two different energies. It is shown that the implementation of light cluster emission in the cascade stage also improves our previous results for residue mass spectra.

Fission fragments from 1 A GeV 238U projectiles irradiating a hydrogen target were investigated by using the fragment separator FRS for magnetic selection of reaction products including ray-tracing and DE-ToF techniques. The momentum spectra of 733 identified fragments were analysed to provide isotopic production cross sections, fission-fragment velocities and recoil momenta of the fissioning parent nuclei. Besides their general relevance, these quantities are also demanded for applications. Calculations and simulations with codes commonly used and recently developed or improved are compared to the data., Comment: 60 pages, 21 figures, 4 tables, 2 appendices (15 pages)

The production cross sections and the kinematical properties of primary residual nuclei have been studied in reactions 197Au + p, 208Pb + p, d, 238U + p, d, and 238U + 208Pb at energies around 1 A GeV. The measured kinematical properties of the residues were also used to disentangle the relevant reaction mechanisms, spallation-evaporation and spallation-fission. The fragment separator FRS at GSI, Darmstadt, was used to separate and identify the reaction products. The measured quantities are important for the design and planning of future radioactive-beam facilities and accelerator-driven systems.

It is well known that intranuclear-cascade models generally overestimate the cross sections for one-proton removal from heavy, stable nuclei by a high-energy proton beam, but they yield reasonable predictions for one-neutron removal from the same nuclei and for one-nucleon removal from light targets. We use simple shell-model calculations to investigate the reasons of this deficiency. We find that a correct description of the neutron skin and of the energy density in the nuclear surface is crucial for the aforementioned observables. Neither ingredient is sufficient if taken separately., Presented at the 11th International Spring Seminar on Nuclear Physics. To be published in Journal of Physics: Conference Series

Experiments performed at Lab. Nat. SATURNE on neutron produced by spallation from proton beams in the range 0.8 - 1.6 GeV are presented. Experimental data compared with codes show a significant improvement of the recent intra-nuclear cascade (J. Cugnon). This is also true in the same way for the neutron production from thick targets. However the model underestimates the energetic neutrons produced in the backward direction and other quantities as residual nuclei cross sections are not accurately predicted.

Some improvements of the Intra-Nuclear Cascade code INCL4 for low energy projectiles are presented and discussed.

The purpose of this paper is twofold. First, we present the extension of the Li\`ege Intranuclear Cascade model to reactions induced by light ions. Second, we describe the C++ version of the code, which it is physics-wise equivalent to the legacy version, is available in Geant4 and will serve as the basis for all future development of the model. We describe the ideas upon which we built our treatment of nucleus-nucleus reactions and we compare the model predictions against a vast set of heterogeneous experimental data. In spite of the discussed limitations of the intranuclear-cascade scheme, we find that our model yields valid predictions for a number of observables and positions itself as one of the most attractive alternatives available to Geant4 users for the simulation of light-ion-induced reactions., Comment: Submitted to Phys. Rev. C

We review and discuss the latest developments of the Liège Intranuclear Cascade model. The new capabilities are illustrated by comparisons with selected experimental data. We also present examples of thick-target calculations performed using particle-transport codes.

We present the experimental method conceived to measure high energy neutrons in the range (200 ≤ E ≤ 1600 MeV). The neutrons produce recoil protons in a liquid hydrogen converter. Momentum evaluation and identification of these protons are made by using a magnetic spectrometer equipped with plastic scintillators and three double-plane ( X - Y ) wire chambers. The response functions of the apparatus are determined using quasi-monoenergetic neutron beams produced by the break-up of deuterons or 3 He on a Be target. The performance of the apparatus is illustrated in the form of a preliminary neutron spectrum.

We present an experimental method based on a time-of-flight technique between the tagged incident particles and a thick liquid NE213 scintillator to measure neutron energy spectra from 3 to 400 MeV at the Saturne synchrotron of Saclay. Efficiency measurements are made using a pulsed neutron source from the Tandem Van de Graaff of Bruyeres-le-Châtel at low energies and a quasi-monoenergetic neutron beam at Saturne up to 50 MeV.

The new version (INCL4.6) of the Li`ege 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 nucleons inside the incident cluster and of the possible fusion reaction at low energy. Performances of the new model concerning nucleon-induced reactions are illustrated. Whenever necessary, the INCL4.6 model is coupled to the ABLA07 deexcitation model and the respective merits of the two models are then tentatively disentangled. Good agreement is generally obtained in the 200 MeV-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 nucleon. 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: production of clusters heavier than alpha particles, longitudinal residue recoil velocity and its fluctuations, total reaction cross section and the residue production cross sections for low energy incident light ions., Comment: 29 pages, 26 figures

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 nucleon 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 nucleon species. © 2013 American Physical Society., A. Jungclaus acknowledges support from the Spanish Ministerio de Ciencia e Innovacion under Contracts No. FPA2009-13377-C02-02 and No. FPA2011-29854-C04-01.

International audience; The collision of 136Xe with a proton and with 12C at 1 GeV per nucleon has been studied in inverse kinematics with the SPALADIN setup at GSI. The detection in coincidence of the final state fragments (projectile residues, neutrons and Z ⩾ 2 charged fragments) with a large geometrical efficiency is provided by the inverse kinematics combined with a large-aperture dipole magnet and large detectors. Such a coincidence, measured on an event basis, allows us to select the excitation energy of the prefragment formed after the nuclear cascade and study its different de-excitation channels such as evaporation of light particles, asymmetric binary decay or multifragmentation. After a short summary of spallation reactions modeling, followed by the description of the setup, some preliminary results will be shown including the cross-sections of the reaction on the proton, compared in particular to other measurements as well as the cross-sections for the various fragment multiplicities. In the last section, we explain our method for the selection of the prefragment excitation energy and give a hint of the variables available in our experiment to study the excitation energy dependence of the prefragment de-excitation mechanism for both reactions.

International audience; Liquid lead-bismuth eutectic (LBE) is often considered as a possible target in spallation neutron sources. Anexperiment has been performed in 2005 at ISOLDE (CERN), in which LBE has been irradiated by 1.0 and 1.4GeV protons and isotopes of astatine, a volatile precursor of Po, have been found. Until recently no modelwas able to reproduce this astatine production, which is due either to double charge exchange reactions,Bi(p,π-xn)At, or to secondary reactions induced by helium nuclei. Recently, both parts of the spallation modelcombination INCL4-Abla have been improved leading to the new versions, INCL4.6-ABLA07. In particular,an additional mechanism to produce light and intermediate mass fragments has been added and special carehas been paid to the low energy reactions. This paper first shows that all the basic features of the differentreactions leading to astatine production are well predicted by the new model. The model, implemented into abeta version of MCNPX2.7 is then used to simulate the ISOLDE experiment. A very good agreement with theexperimental data is observed.

International audience; In the framework of the European Spallation Source (ESS) project, works on ESS target design needcomputational tools and the validation of these tools must be done to estimate accuracy of the calculationresults. INCL4.6 and Abla07 have been implemented in a beta version of MCNPX2.7 to be able to use themwhen transport is needed as ESS spallation target design. Within ESS project, we decided to benchmark ourspallation model on excitation functions (p+W) to assess the reliability on a thin target according to theproduced isotope and the projectile energy. We focused on a list of hazardous nuclei given by previous ESScalculations and from previous experiments. These results, which can of course help to estimate uncertaintiesas designing ESS target, were supplemented by another benchmark done with a thick tungsten target andgiving isotope production along the beam axis and radially as well.

Nuclear data for neutron-induced reactions in the intermediate energy range of 20 to 200 MeV are of importance for several different applications, notably accelerator-driven incineration of nuclear waste. The Medley setup located at The Svedberg Laboratory in Uppsala, Sweden was used for a series of measurements of p, d, t, 3 He and alpha particle production from 175 MeV neutrons on various target nuclei. Medley uses an arrangement of 8 detector telescopes placed at angles from 20 to 160 degrees relative to the neutron beam to register event and discriminate among the particle types. Using the ΔE-ΔE-E technique we were able to measure double-differential cross sections over a wide dynamic range. This paper describes the experimental set-up, summarizes the data analysis and reports on recent changes in the previously reported preliminary data set on bismuth. Experimental data are compared with several different model calculations. In this paper we specifically compare the experimental results with INCL4 intra-nuclear cascade calculations combined with the ABLA de-excitation code. Considering the fact that the experimental data are obtained at an energy normally considered too low for intra-nuclear cascade calculations, we do find some systematic difference but generally reasonable agreement.

We use the tools of hybrid intranuclear-cascade/nuclear-de-excitation models to evaluate the sensitivity of several physical observables to the inclusion of a multifragmentation stage in the deexcitation chain and assess the need for a multifragmentation model in the quantitative description of p + 56 Fe and p + 136 Xe reactions at 1-GeV incident energy. We seek clear signatures of multifragmentation by comparing different state-of-the-art de-excitation models coupled with intranuclear-cascade models and by focusing on discriminating observables such as correlations and fragment longitudinal-velocity distributions. None of the considered observables can be unambiguously interpreted as a multifragmentation footprint. The experimental data are best described as originating from sequential binary decays. However, no de-excitation model can reproduce the experimental longitudinal-volocity distributions from 1-GeV p + 136 Xe.

We use the tools of hybrid intranuclear-cascade/nuclear-deexcitation models to evaluate the sensitivity of several physical observables to the inclusion of a multifragmentation stage in the deexcitation chain and assess the need for a multifragmentation model in the quantitative description of $p$ + ${}^{\text{5}6}$Fe and $p$ + ${}^{\text{1}36}$Xe reactions at 1-GeV incident energy. We seek clear signatures of multifragmentation by comparing different state-of-the-art deexcitation models coupled with intranuclear-cascade models and by focusing on discriminating observables such as correlations and fragment longitudinal-velocity distributions. None of the considered observables can be unambiguously interpreted as a multifragmentation footprint. The experimental data are best described as originating from sequential binary decays. However, no deexcitation model can reproduce the experimental longitudinal-velocity distributions from 1-GeV $p$ + ${}^{\text{1}36}$Xe.

Spallation neutron production in proton induced reactions on Pb targets at 0.8, 1.2, and 1.6 GeV has been measured at the SATURNE accelerator. Double-differential cross sections were obtained over a broad angular range from which averaged neutron multiplicities per reaction were inferred for energies above 2 MeV. The results are compared with calculations performed with a high energy transport code including two different intranuclear cascade (INC) models: it is shown that the Cugnon INC model gives a better agreement with the data than the Bertini one, mainly because of improved nucleon-nucleon cross sections and Pauli blocking treatment. © 1999 The American Physical Society.