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This overview introduces nuclear resonant scattering techniques with synchrotron radiation. After a focus on nuclear resonant scattering in general, two popular methods with a wide range of applications, nuclear resonant inelastic X-ray scattering and synchrotron Mossbauer spectroscopy are described in greater detail. The inelastic method provides specific vibrational information such as the phonon density of states. The Mossbauer method permits determination of hyperfine interactions. Nuclear resonant techniques take full advantage of the unique properties of synchrotron radiation: intensity, collimation, time structure, and polarization. As a result both methods discussed here have led to novel applications for materials under extreme conditions, proteins with biological functionality, and magnetic nanostructures.

Differential, integral, momentum-transfer, viscosity, inelastic and total cross sections as well as spin asymmetries are calculated for electron and positron scattering from the gold atom with nuclear spin 3 2 . The impact energies of the projectiles range from low-energy atomic physics regime to high-energy nuclear physics. This is accomplished by employing two different theoretical approaches, applicable for the aforesaid two domains of energies, and are based on the partial-wave analysis. In one approach, the phase shifts analysis is done at E i 1 MeV using the Dirac relativistic equations. In another approach, at E i ≥ 100 keV, the same analysis is carried out with the distorted wave Born approximation to account for the projectile scattering including the magnetic effect as well. Predictions are reported for 1 eV ≤ E i ≤ 0.5 GeV electrons and positrons colliding with 197 Au target. In addition, we report here systematically the details of the critical minima in the elastic differential cross sections. To date, neither any experimental nor any theoretical study on the critical minima of electron/positron–Au scattering system is available in the literature. Our results of other observables are compared with the available experimental data and other calculations and are found to produce quite reasonable agreements with two forms of data.

Recently, the XENON1T experiment has reported the possible detection of an excess in the electronic recoil spectrum. Such an excess may indicate the presence of new physics. In this work, we suggest that the scattering of mirror electrons with ordinary electrons through photon$-$mirror photon kinetic mixing with parameter $\epsilon \sim 10^{-12}(n_{\rm e'}/0.2{\rm cm^{-3}})^{-1/2}({v_{\rm c}^0/5\times 10^{9}~{\rm cm~s^{-1}}})^{1/2}$ may account for the excess electronic recoil events in XENON1T, where $n_{\rm e'}$ is the density of mirror electron and $v_{\rm c}^0$ is the cutoff velocity of the mirror electron arriving at the earth. Interestingly, this parameter to interpret the excess of XENON1T electronic recoil spectrum are consistent with the constrains of Darkside50., Comment: 5 pages, 3 figures

Recently published data on the Sachs electric form factor by the PRad collaboration (Nature {\bf 575}, 147-151) are analyzed to investigate their consistency with the known proton charge radius from muonic and electronic hydrogen spectroscopy, as well as theoretical predictions from dispersively improved chiral perturbation theory. It is shown that the latter is fully consistent with the data, and pointers are given how future $e-p$ scattering experiments can lead to an improvement of our knowledge of the form factor in the low-momentum-transfer regime., Comment: 16 pages, 4 figures, 37 references

The isovector and isoscalar ND s-wave scattering lengths are extracted by fitting to the LHCb data of the p D 0 invariant-mass distribution in the decay Λ b → π − p D 0 , making use of the cusp effect at the n D + threshold. The analysis is based on a coupled-channel nonrelativistic effective field theory. We find that the real part of the isovector ND scattering length is unnaturally large due to the existence of a near-threshold state with a mass around 2.8 GeV. The state is consistent with the Σ c ( 2800 ) + resonance observed at Belle. Our results suggest that it couples strongly to the ND channel in an s-wave, and that its quantum numbers are J P = 1 / 2 − . The strong cusp behavior at the n D + threshold can be verified using updated LHCb data.

The anti-kaon nucleon scattering lengths resulting from a Hamiltonian effective field theory analysis of experimental data and lattice QCD studies are presented. The same Hamiltonian is then used to compute the scattering length for the $K^- d$ system, taking careful account of the effects of recoil on the energy at which the $\bar{K}N$ T-matrices are evaluated. These results are then used to estimate the shift and width of the $1S$ levels of anti-kaonic hydrogen and deuterium. The $K^- p$ result is in excellent agreement with the SIDDHARTA measurement. In the $K^- d$ case the imaginary part of the scattering length and consequently the width of the $1S$ state are considerably larger than found in earlier work. This is a consequence of the effect of recoil on the energy of the $\bar{K}N$ energy, which enhances the role of the $\Lambda(1405)$ resonance., Comment: 7 pages, 3 figures, published version

We present a theoretical study on the calculations of various cross sections related to the scattering of electrons and positrons from indium atoms. Our calculations cover the energy range 1 eV ⩽ E i ⩽ 0.5 GeV. We have employed two approaches, applicable for two domains of energy, based on the Dirac partial-wave analysis. In one approach, we have used both the atomic and nuclear potentials to calculate the cross sections for the low and intermediate energies. The other approach, valid for the high-energy scattering, utilizes only the nuclear potential for the phase-shift analysis, and considers the magnetic scattering from the nucleus too. We report the calculations of differential, integral, momentum-transfer and viscosity cross sections along with the spin asymmetries for the elastic scattering of electrons and positrons. Moreover, we have analyzed the critical minima in the elastic differential cross sections, and also computed the absorption and total cross sections. Our results agree reasonably with the available experimental data and other calculations.

Stimulated by recent indications that the binding energy of the hypertriton could be significantly larger than so far assumed, requirements of a more strongly bound $^3_\Lambda {\rm H}$ state for the hyperon-nucleon interaction and consequences for the binding energies of $A=4,5$ and $7$ hypernuclei are investigated. As basis a $YN$ potential derived at next-to-leading order in chiral effective field theory is employed, Faddeev and Yakubovsky equations are solved to obtain the corresponding $3$- and $4$-body binding energies, respectively, and the Jacobi no-core shell model is used for $^5_\Lambda$He and $^7_\Lambda$Li. It is found that the spin-singlet $\Lambda p$ interaction would have to be much more attractive which can be, however, accommodated within the bounds set by the available $\Lambda p$ scattering data. The binding energies of the $^4_\Lambda {\rm He}$ hypernucleus are predicted to be closer to the empirical values than for $YN$ interactions that produce a more weakly bound $^3_\Lambda {\rm H}$. The quality of the description of the separation energy and excitation spectrum for $^7_\Lambda$Li remains essentially unchanged., Comment: 8 pages, 3 figures; version that was published in Phys. Lett. B

Publisher Summary This chapter focuses on spontaneous light scattering and acoustooptics. Spontaneous light scattering means light scattering under conditions such that the optical properties of the material system are unmodified by the presence of the incident light beam. Several physical processes can lead to light scattering. One of the processes is Raman scattering that results from the interaction of light with the vibrational modes of the molecules constituting the scattering medium. Raman scattering can equivalently be described as the scattering of light from optical phonons. Brillouin scattering is the scattering of light from sound waves, that is, from propagating pressure (and hence density) waves. Brillouin scattering can also be considered to be from acoustic phonons. In RayLeigh scattering or Rayleigh-center scattering, light is scattered because of nonpropagating density fluctuations. Formally, it can be described as scattering from entropy fluctuations. It is known as quasielastic scattering because it induces no frequency shift. The scattering of light from sound waves can also be applied to the situation, in which the sound wave is applied to the interaction region externally by means of a transducer. Such acoustooptic devices are useful as intensity or frequency modulators for laser beams or as beam deflectors. Acoustooptic devices are commonly classified as falling into one of two regimes; namely, Bragg scattering and Raman-Nath scattering.

The ring current decay occurs during the recovery phase of a geomagnetic storm when the particles’ injection is no longer strong enough to overcome the loss processes. The major ring current loss processes and their aeronomical effects are described in this chapter. The most important among the collisional loss processes is charge exchange, where ring current ions are neutralized on collision with thermal exospheric hydrogen atoms and produce energetic neutral atoms (ENAs) which are either lost in space or precipitate down to the atmosphere. Coulomb collisions between energetic ring current ions and coexisting low-energy plasmaspheric populations result in energy transfer from the fast moving to the thermal particles and in angular deflection of the particles. The magnetospheric energy is transported down the magnetic field lines and creates ionospheric electron and ion temperature enhancements and optical emissions known as stable auroral red (SAR) arcs. Scattering of ring current ions into the loss cone due to resonant interactions with electromagnetic ion cyclotron (EMIC) waves occurs on short timescales and leads to ion precipitation and the generation of detached proton arcs. Likewise, ring current electrons are scattered in pitch angle by whistler-mode waves and their precipitation at low altitudes affects significantly the ionospheric conductivity. In addition, particles are lost as they flow out to the dayside magnetopause or as they are moved to the loss cone by magnetospheric convection or field line curvature scattering. The ring current decay leads to the restoration of the surface magnetic field of the Earth to its prestorm values.

We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the α – α system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the α – α and α – n systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

Stimulated Raman scattering (SRS) excited by incoherent light is studied via particle-in-cell simulations. It is shown that a large bandwidth of incoherent light can reduce the growth of SRS and electron heating considerably in the linear stage. However, different components of the incoherent light can be coupled by the Langmuir waves, so that stimulated Raman backward scattering can develop. When the bandwidth of incoherent light is larger than the Langmuir wave frequency, forward SRS can be seeded between different components of the incoherent light. The incoherent light can only increase the time duration for nonlinear saturation but cannot diminish the saturation level obviously. Keywords: Stimulated Raman scattering, Instability suppression, Incoherent light, Inertial confinement fusion, PACS Codes: 52.25.Os, 52.35.-g, 52.38.Bv

We present a dynamical explanation of the hollowness effect observed in proton-proton scattering at $\sqrt s\!=\!7$ TeV. This phenomenon, not observed at lower energies, consists in a depletion of the inelasticity density at zero impact parameter of the collision. Our analysis is based on three main ingredients: we rely gluonic hot spots inside the proton as effective degrees of freedom for the description of the scattering process. Next we assume that some non-trivial correlation between the transverse positions of the hot spots inside the proton exists. Finally we build the scattering amplitude from a multiple scattering, Glauber-like series of collisions between hot spots. In our approach, the onset of the hollowness effect is naturally explained as due to the diffusion or growth of the hot spots in the transverse plane with increasing collision energy., 4 pages, 3 figures

The second Born approximation has been applied to calculate the triple and double differential cross sections for ionization of hydrogen atoms by 75 keV proton and antiproton impacts. The closure relation is used to perform the summation over the intermediate states in the second Born approximation. The triple differential cross sections (TDCSs) are calculated at different values of scattering angle θs and ejected energy Ee. The double differential cross sections (DDCSs) have been measured as a function of the projectile scattering angle and the electronics eject energy. The calculations are performed for emission of the electron into the collision plane with the ejected energies 16.4, 26.4, 36.4 and 39.4 eV. The resulting differential cross sections are compared with experimental and theoretical previous available results. Keywords: Single ionization, Second Born approximation, Differential cross section, Ion-atom collision

The proton charge-radius determinations from the electromagnetic form-factor measurements in electron-proton scattering require an extrapolation to zero momentum transfer ($Q^2=0$) which is prone to model-dependent assumptions. We show that the data at finite momentum transfer can be used to establish a rigorous lower bound on the proton charge radius. Using the available $ep$ data at low $Q^2$, we obtain $R_E > 0.850(1)$ fm as the lower bound on the proton radius. This reaffirms the discrepancy between the $ep$ and muonic-hydrogen values, while bypassing the model-dependent assumptions that go into the fitting and extrapolation of the $ep$ data., 8 pages, 4 figures, 1 table; new analysis (figure 4) added, text revised accordingly, typos corrected

The Isoscalar Giant Monopole Resonance (ISGMR) and the Isoscalar Giant Dipole Resonance (ISGDR) compression modes have been studied in the doubly-magic unstable nucleus 56Ni. They were measured by inelastic α-particle scattering in inverse kinematics at 50MeV/u with the MAYA active target at the GANIL facility. The centroid of the ISGMR has been obtained at Ex=19.1 ±0.5MeV. Evidence for the low-lying part of the ISGDR has been found at Ex=17.4 ±0.7MeV. The strength distribution for the dipole mode shows similarity with the prediction from the Hartree–Fock (HF) based random-phase approximation (RPA)[1]. These measurements confirm inelastic α-particle scattering as a suitable probe for exciting the ISGMR and the ISGDR modes in radioactive isotopes in inverse kinematics This work was supported by the European Commission within the Seventh Framework Programme through IA-ENSAR (contract No. RII3-CT-2010-262010) and GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany, and the United States National Science Foundation (Grants Number PHY-1068192 and PHY-1419765) SI

The angular distribution of 12 C + 12 C scattering at an incident energy of 100 A MeV has been measured. The elastic and inelastic scatterings in 12 C to the excitation energies of up to ∼ 45 MeV were measured simultaneously for the first time with the high-resolution Grand Raiden spectrometer at the Research Center for Nuclear Physics (RCNP). The angular distributions of the elastic scattering to the ground state ( 0 1 + ) and inelastic scattering to the 4.44 MeV ( 2 1 + ) excited state were precisely obtained in the angular range of 1.0°–7.5° with a step of 0.1°. Additionally, the angular distribution was obtained for the sum of the cross sections for excitation energies above the 4.44 MeV state up to 11 MeV, which includes the 7.65 MeV ( 0 2 + ), 9.64 MeV ( 3 1 − ), and 10.30 MeV ( 2 2 + ) states, in addition to probably the simultaneous excitation of the 4.44 MeV state in the projectile and the target nuclei. Those combined data provide a means to study the effects of channel coupling on the elastic cross section. The observed angular distributions are compared with theoretical calculations based on three double-folding models with complex G-matrix interactions, the CEG07b, MPa, and ESC models. The importance of three-body repulsive forces included in the CEG07b and MPa models will be discussed.

We report the first measurements of the transverse (Px and Py) and longitudinal (Pz) components of the polarization transfer to a bound proton in the deuteron via the H2(e→,e′p→) reaction, over a wide range of missing momentum. A precise determination of the electron beam polarization reduces the systematic uncertainties on the individual components to a level that enables a detailed comparison to a state-of-the-art calculation of the deuteron using free-proton electromagnetic form factors. We observe very good agreement between the measured and the calculated Px/Pz ratios, but deviations of the individual components. Our results cannot be explained by medium modified electromagnetic form factors. They point to an incomplete description of the nuclear reaction mechanism in the calculation.

Ion scattering techniques have demonstrated capability to probe the composition and structure of the surface region of materials with a depth selectivity that depends on projectile energy. At low energies, it can provide surface atomic layer-specific information, while at high energies, it can provide information to depths of over a micron. Developments in equipment, the nature of the projectiles used, and the theoretical understanding of the processes involved in scattering have allowed the lowest-energy technique using projectiles

Elementary reactive processes of atoms and molecules at metal surfaces are often accompanied or facilitated by the excitation of electron–hole pairs. The actual relevance of these excitations in the rate of the different processes depends on several static and dynamical factors. Here, we summarize the current theoretical understanding of how these nonadiabatic effects affect some common gas–surface processes: the adsorption, relaxation, and scattering of atoms and molecules, as well as the recombination of adsorbates. A brief description of the local density friction approximation (LDFA) used in these theoretical studies is also provided.

For the detection of low energetic neutral atoms for the remote sensing of space plasmas, charge state conversion surfaces are used to ionize the neutrals for their subsequent measurement. We investigated a boron-doped Chemical Vapor Deposition (CVD) diamond sample for its suitability to serve as a conversion surface on future space missions, such as NASA’s Interstellar Mapping and Acceleration Probe. For H and O atoms incident on conversion surface with energies ranging from 195 to 1000 eV and impact angles from 6° to 15° we measured the angular scattering distributions and the ionization yields. Atomic force microscope and laser ablation ionization mass spectrometry analyses were applied to further characterize the sample. Based on a figure-of-merit, which included the ionization yield and angular scatter distribution, the B-doped CVD surface was compared to other, previously characterized conversion surfaces, including e.g. an undoped CVD diamond with a metallized backside. For particle energies below 390 eV the performance of the B-doped CVD conversion surfaces is comparable to surfaces studied before. For higher energies the figure-of-merit indicates a superior performance. From our studies we conclude that the B-doped CVD diamond sample is well suited for its application on future space missions.

The isoscalar giant monopole resonance (ISGMR) strength distribution in $^{24}$Mg has been determined from background-free inelastic scattering of 386-MeV $\alpha$ particles at extreme forward angles, including 0$^{\circ}$. The ISGMR strength distribution has been observed for the first time to have a two-peak structure in a light-mass nucleus. This splitting of ISGMR strength is explained well by microscopic theory in terms of the prolate deformation of the ground state of $^{24}$Mg., Comment: 5 pages, 4 figures; to be published in Phys. Lett. B

The neutron-proton effective $k$-mass splitting in asymmetric nucleonic matter of isospin asymmetry $\delta$ and normal density is found to be $m^{*}_{n-p}\equiv(m^{*}_{n}-m^{*}_{p})/m=(0.41 \pm0.15)\delta$ from analyzing globally 1088 sets of reaction and angular differential cross sections of proton elastic scattering on 130 targets with beam energies from 0.783 MeV to 200 MeV, and 1161 sets of data of neutron elastic scattering on 104 targets with beam energies from 0.05 MeV to 200 MeV within an isospin dependent non-relativistic optical potential model. It sets a useful reference for testing model predictions on the momentum dependence of the nucleon isovector potential necessary for understanding novel structures and reactions of rare isotopes., Comment: Published version, Physics Letters B743 (2015) 408

Great success has been achieved in the modeling of gas-surface elementary processes by the use of the Born-Oppenheimer approximation. However, in metal surfaces low energy electronic excitations are generated even by thermal and hyperthermal molecules due to the absence of band gaps in the electronic structure. This shows the importance of performing dynamical simulations that incorporate non-adiabatic effects to analyze in which way they affect most common gas-surface reactions. Here we review recent theoretical developments in this problem and their application to the study of the effect of electronic excitations in the adsorption and relaxation of atoms and molecules in metal surfaces, in scattering processes, and also in recombinative processes between impinging atoms and adsorbates at the surface. All these studies serve us to establish what properties of the gas-surface interaction favor the excitation of low-energy electron-hole pairs. A general observation is that the nature of these excitations usually requires long lasting interactions at the surface in order to observe deviations from the adiabatic behaviour. We also provide the basis of the local density friction approximation (LDFA) that have been used in all these studies, and show how it has been employed to perform ab initio molecular dynamics with electronic friction (AIMDEF). As a final remark, we will shortly review on recent applications of the LDFA to successfully simulate desorption processes induced by intense femtosecond laser pulses., The authors acknowledge financial support by the Gobierno Vasco-UPV/EHU project IT756-13 and the Spanish Ministerio de Economía y Competitividad Grant No. FIS2016-76471-P.

A review of activities in the theory of two-dimensional electron systems at the Rzhanov Institute of Semiconductor Physics of the Siberian Branch of the Russian Academy of Sciences is presented. The topics considered in this chapter include: surface scattering of electrons in two-dimensional systems, electron states of charged impurities, two-dimensional electron-impurity systems in a strong magnetic field, photogalvanic effect in two-dimensional systems, electron states in curved low-dimensional systems, and electron and exciton states in graphene. In addition, collective effects in one- and two-dimensional single- and multicomponent systems are analyzed, including plasma waves, Wigner crystallization, and screening. Screening of the electrostatic field by dipole excitons (including their Bose condensate) is considered.

This article describes a quantum mechanical reactive scattering program for atom–diatom chemical reactions that we have written during the past several years. The program uses a coupled-channel hyperspherical coordinate method to solve the Schrodinger equation for the motion of the three nuclei on a single Born–Oppenheimer potential energy surface. It has been tested for all possible deuterium-substituted isotopomers of the H + H 2 , F + H 2 , and Cl + H 2 reactions, and tried and tested potential energy surfaces for these reactions are included within the program as Fortran subroutines.

When monochromatic light is scattered by a molecule or crystal, photons of the incident radiation may be annihilated and, at the same time, remitted as dipole radiation with a different energy or frequency. This frequency shift with respect to the incident radiation is balanced by excitations of the scattering medium, as phonons, magnons or electronic excitations. Raman light scattering (RS) is frequently used as a nondestructive characterization technique with a very high sensitivity for optical phonons with small wave vectors close to the center of the Brillouin zone.

Hydrogen imaging with sub-μm lateral resolution and sub-ppm sensitivity has become possible with coincident proton–proton (pp) scattering analysis (Reichart et al., 2004). Depth information is evaluated from the energy sum signal with respect to energy loss of both protons on their path through the sample. In first order, there is no angular dependence due to elastic scattering. In second order, a path length effect due to different energy loss on the paths of the protons causes an angular dependence of the energy sum. Therefore, the energy sum signal has to be de-convoluted depending on the matrix composition, i.e. mainly the atomic number Z, in order to get a depth calibrated hydrogen profile. Although the path effect can be calculated analytically in first order, multiple scattering effects lead to significant deviations in the depth profile. Hence, in our new approach, we use the CORTEO Monte-Carlo code (Schiettekatte, 2008) in order to calculate the depth of a coincidence event depending on the scattering angle. The code takes individual detector geometry into account. In this paper we show, that the code correctly reproduces measured pp-scattering energy spectra with roughness effects considered. With more than 100 μm thick Mylar-sandwich targets (Si, Fe, Ge) we demonstrate the deconvolution of the energy spectra on our current multistrip detector at the microprobe SNAKE at the Munich tandem accelerator lab. As a result, hydrogen profiles can be evaluated with an accuracy in depth of about 1% of the sample thickness.

Low-energy ion scattering (LEIS) is an analytical tool that provides information on the atomic composition of the outer surface, when noble gas ions are used as projectiles. In fact, quantitative composition analysis is currently done on a huge variety of materials, including catalysts and organic materials. The information on the surface composition is contained in the signal of backscattered ions (typically 1–3 keV He + ,Ne + ). In order to translate the LEIS signal to an elemental surface concentration all factors determining the LEIS signal must be known. These are in particular the scattering cross section and the ion fraction of the backscattered particles. The scattering cross section, which is due to the screened electrostatic potential between target atom and projectile, is well-known for the prevailing conditions of LEIS. It is an intriguing fact that, despite the large quantity of successful applications, the charge exchange processes in LEIS are not yet fully understood. It is e.g. not known why in LEIS for a given atomic species on the surface the signal usually does not depend on which other species are present (absence of matrix effects). Significant progress has recently been made in the understanding of the underlying charge exchange processes. Therefore, the aim of this review is twofold: on the one hand, to summarize the present understanding of the factors that determine the ion fraction of the scattered projectiles in LEIS, i.e. charge exchange processes. On the other hand, to summarize how quantitative surface composition analysis can be accomplished. In addition, we critically review publications that deal with surface composition analysis by LEIS, and analyze in which cases and by what means this was achieved and where and why it was successful or failed. After reading this review the reader will be able to deal with the pitfalls encountered in LEIS and to choose preferred experimental conditions for quantitative surface composition analysis.

Coherent to incoherent differential cross-section ratios of Au have been measured for several polar scattering angles (90°, 100°, 110°, 120° and 130°) and azimuthal angles (30°, 20°, 10°, 0°, −10°, and −20°) at 59.54 keV photon energy by using high purity germanium (HPGe) detector, which has a resolution of 199.6 eV at the 5.9 keV. The samples were excited with 59.54 keV gamma rays emitted from 3.7×10 9 Bq (100 mCi) Am 241 point source. The intensity ratios were corrected due to the photopeak efficiency of gamma detector and absorption of photons in the target and air. The experimental values obtained in this study were compared with those estimated on the basis of the non-relativistic form factors and relativistic form factors.

7 págs.; 6 figs., © 2015 Elsevier B.V. All rights reserved. The independent atom model representation (IAM) in combination with the additivity rule (AR) is customary accepted as a good approximation to describe electron and positron scattering processes with polyatomic molecules at intermediate and high energies (typically above 100 eV). Within this approach, interference terms are not properly evaluated and are usually ignored in the cross section calculations. However, through a numerical solution of the Lippmann-Schwinger equation for three dimensional multicentre potentials we here demonstrate how interference terms can affect to the calculated differential and integral cross section values even at such relatively high energies. Practical corrections to the AR approach for both differential and integral electron and positron scattering cross section calculations from molecules are also proposed., This study has been partially supported by the Spanish Ministerio de Economía y Competitividad (project FIS2012-31230).

4 págs.; 4 figs., © 2015 Elsevier B.V. © 2015 Elsevier B.V. All rights reserved. Experimental evidence of synthetic single-crystal diamond amorphization under the effect of irradiation with swift heavy ions is shown. The type of sharp thresholding behavior that characterizes electronic damage is not observed within a range of electronic stopping power covering up to 14 keV/nm. Amorphization is assessed by Rutherford Back Scattering Channeling (RBS-c) measurements done with light ions, after swift heavy ion irradiation. Results are analyzed and discussed in order to confirm the hypothesis of a nuclear damage-induced process, whereby it is concluded that electronic effects are not relevant in the studied range of stopping powers. The evolution of the amorphized fraction as a function of the irradiated fluence and nuclear stopping power is measured and discussed as well., We acknowledge funding from Spain's MINECO project: MAT-2011-28379-C03-02.

This article covers the physical processes responsible for solar and thermal radiation as well as the physical laws governing such processes, properties of gaseous absorptions, common algorithms used to solve the radiative transfer in the absence of scattering, radiative properties of the Earth's atmosphere, and general thermodynamics in the context of the radiation field.

The proton and electron inner structures are considered in the frame of unified non-local theory. From calculations follow that proton and electron can be considered like charged balls (shortly CB-model) in which charges are concentrated mainly in the shell of these balls. The proton-electron collision in the frame of the CB-model should be considered as collision of two resonators . Application of the CB – model allows to explain a number of character effects observed by inelastic electron – proton collisions (including the initial and final electron energies and the scattering angles) without application of the quark theory.

5 págs.; 4 figs., An improvement of the screening-corrected Additivity Rule (SCAR) is proposed for calculating electron and positron scattering cross sections from polyatomic molecules within the independent atom model (IAM), following the analysis of numerical solutions to the three-dimensional Lippmann-Schwinger equation for multicenter potentials. Interference contributions affect all the considered energy range (1-300 eV); the lower energies where the atomic screening is most effective and higher energies, where interatomic distances are large compared to total cross sections and electron wavelengths. This correction to the interference terms provides a significant improvement for both total and differential elastic cross sections at these energies. © 2015 Elsevier B.V. All rights reserved, This study has been partially supported by the Spanish Ministerio de Economía y Competitividad (project FIS2012-31230) and the EU COST programme (Action CM1301). L.E.-G. is supported by the EU FP7-PEOPLE-2013-ITN programme (ARGENT project).

Liquid Hg undergoes the metal–nonmetal (M–NM) transition when it is expanded from 13.6 g cm −3 at ambient conditions to 9 g cm −3 at high temperature and high pressure. To investigate collective and single particle motions in expanded fluid Hg, we have made inelastic X-ray scattering experiments and obtained the dynamic structure factor, S ( Q , ω ), of fluid Hg. We analyzed S ( Q , ω ) within the framework of generalized hydrodynamics and found that the excitation energies of collective modes disperse three times as fast as the hydrodynamic sound velocity in the M–NM transition region at 9 g cm −3 . The results indicate the existence of fast sound in expanded fluid Hg accompanying the metal–non-metal transition and strongly hint that fluctuations intrinsic to the M–NM transition are induced on atomic length scale and sub-picosecond time scale.

9 pags.; 6 figs.; 1 app., We present a study of electron and positron transport in water in both the gaseous and liquid states using a Boltzmann equation analysis and a Monte-Carlo simulation technique. We assess the importance of coherent scattering processes when considering transport of electrons/positrons in dense gases and liquids. We highlight the importance of electron and positron swarm studies and experiments as a test of the accuracy and completeness of cross-sections, as well as a technique for benchmarking Monte-Carlo simulations. The thermalization of low-energy positrons (, G.G. was partially supported by the Spanish Ministerio de Economia e Innovacion (Project FIS2009-10245).

IWM-EC 2014 – International Workshop on Multi facets of EoS and Clustering., The GLObal ReactIon Array (GLORIA) has been designed in order to study direct nuclear reactions induced by exotic nuclei at energies close to the Coulomb barrier. The detector array consists of six silicon particle-telescopes arranged in a very close geometry around a 30° rotated-target system, allowing the measurement of reaction fragments in a continuous angular range from 15° to 165° (Lab.). GLORIA has been used for the first time at the SPIRAL/GANIL facility at Caen (France) to study the scattering of the system 8He+208Pb at the collision energies of 16 and 22 MeV., This work was supported in part by the Grant FPA2010-22131-C02-01 (FINURA) from the Spanish Ministry of Economy and Competitiveness, the Grant N202 033637 from the Ministry of Science and Higher Education of Poland and the Contract EUI2009-04163 (EUROGENESIS) from the European Science Foundation.

In this work we present a study of the adsorption of S on the surfaces of the noble metals Au(111) and Ag(111) by ion scattering performed in the forward direction. Low energy electron diffraction patterns taken at specific exposures were used to identify the S phases. Photoemission and Auger electron spectroscopies were used to determine the coverage dependence on dose. All the techniques indicate that the adsorption process is different in both surfaces since very low coverages. Analysis of the scattering peak intensity and shape provides evidence about the coexistence of Ag substrate atoms together with the S adsorbate in the top layer for all the coverages investigated. For Au we discard this effect for coverages up to 0.3 ML and measure a small Au recoil peak coming from the top layer for the high coverage regime (0.5 ML). At intermediate coverages the shape of the scattering spectra presents a strong dependence on azimuth that is attributed to S-S shadowing and consistent with the diffraction symmetry. The variations on azimuth are analyzed with a simple shadowing calculation that uses the crystallographic model proposed by Yu et al. (2007) [1]. Fil: Tosi, Ezequiel. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ruano Sandoval, Gustavo Daniel. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bengió, Silvina. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Salazar Alarcón, Leonardo. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sánchez, Esteban Alejandro. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Khalid, Mohamed. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina Fil: Grizzi, Oscar. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martiarena, María Luz. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Zampieri, Guillermo Enrique. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

A high-brightness hydrogen/deuterium atomic beam source is presented. The apparatus, previously used in electron scattering experiments with tenser-polarized deuterium (Ferro-Luzzi et al., Phys. Rev. Lett. 77 (1996) 2630; van den Brand et al., Phys. Rev. Lett. 78 (1997) 1235; Zhou et al., Phys. Rev. Lett. 82 (1998) 687; Bouwhuis et al., Phys. Rev. Lett. 82 (1999) 3755), was configured as a source for internal target experiments to measure single- and double-polarization observables, with either polarized hydrogen or vector/tensor polarized deuterium. The atomic beam intensity was enhanced by a factor of similar to 2.5 by optimizing the Stern-Gerlach focusing system using high tip-field ( similar to 1.5 T) rare-earth permanent magnets, and by increasing the pumping speed in the beam-formation chamber. Fluxes of (5.9 +/- 0.2) x 10(16) H-1/s were measured in a empty set 12 mm x 122 mm compression tube with its entrance at a distance of 27 cm from the last focusing element. The total output flux amounted to (7.6 +/- 0.2) x 10(16) H-1/s. (C) 2000 Elsevier Science B.V. All rights reserved.

Recent cyclotron resonance experiments in n-type CdS at ultra-high magnetic fields have revealed a well-pronounced maximum of the electron cyclotron mass as a function of temperature. These experimental data are interpreted within a model which takes into account the interaction of the conduction electrons with LO phonons and with nonpolar optical phonons. The piezoelectric electron–phonon interaction and the electron scattering by randomly distributed defects with a short-range potential are also treated. We show that the observed behaviour of the cyclotron mass can be explained in terms of an interplay between several scattering mechanisms.

Computer modeling of sheaths with dust particles, performed by means of the modified PIC method with self-consistent dust particle charge as well as electron and ion velocity distribution functions, show that dust particles can strongly influence the properties of these sheaths. This influence is caused by a selective collection and a scattering of electrons and ions by dust particles with self-consistent electric charge. Dust particles can strongly change an ion flux so that this flux is not constant in the sheath. That causes a change of both the well-known Bohms criterion on the sheath boundary and the other sheath parameter distributions.

A measurement of the proton spin structure function g1p(x,Q^2) in deep-inelastic scattering is presented. The data were taken with the 27.6 GeV longitudinally polarised positron beam at HERA incident on a longitudinally polarised pure hydrogen gas target internal to the storage ring. The kinematic range is 0.021, Comment: 7 pages, 3 figures, 1 table, RevTeX latex

Accepted: 1997-11-18, 資料番号: SA1001549000

New physics can be accessed by scattering polarized electrons from a polarized He-3 internal gas target. It is discussed how the asymmetries for the reactions ((e) over right arrow, e''), ((e) over right arrow, e''p) ((e) over right arrow, e''n) ((e) over right arrow, e''d) and ((e) over right arrow, e''pn) may provide precise information on the S'' and the D-wave parts of the He-3 ground-state wave function, the neutron form factors, and the role of spin-dependent reaction mechanism effects. The experiment uses up to 900 MeV (polarized) electrons from the AmPS storage ring in Amsterdam, Netherlands, in combination with large acceptance electron and hadron detectors.

We present high precision benchmark calculations for the triton binding energy using the most recent, phase equivalent realistic nucleon-nucleon (NN) potentials and the Tuscon-Melbourne pi-pi three-nucleon force (3NF). That 3NF is included with partial waves up to a total two-body angular momentum of j_max=6. It is shown that the inclusion of the 3NF slows down the convergence in the partial waves and j_max=5 is needed in order to achieve converged results within a few keV. We adjust the cut-off parameter Lambda in the form factors of the Tuscon-Melbourne 3NF separately for the different NN potentials to the triton binding energy. This provides a set of phenomenological three-nucleon Hamiltonians which can be tested in three-nucleon scattering and systems with A>3. A connection between the probability to find two nucleons at short distances in the triton and the effect of that 3NF on the triton binding energy is pointed out.

Publisher Summary This chapter describes the spectroscopy of mesonic atoms. The field of the spectroscopy of mesonic atoms has developed because of the large flux of meson beams available from high-energy accelerators. Mesonic atoms exist in the last stage of the process in which negative mesons are slowed down and absorbed by matter. They are atoms in which the mesons have been captured into Bohr-like orbits surrounding the nuclei. The larger mass of the meson causes these mesonic orbits to be in closer and more tightly bound than the corresponding electronic orbits, by the ratio of the masses. An advantage of mesonic spectroscopy over ordinary electronic spectroscopy is that, because of the heavier mass of the mesons and the orbits being closer to the nucleus, all effects in electronic spectroscopy are enhanced by a large factor, and the possibility of studying the unavailable properties of the nucleus is made feasible.

n-Undecane ( C 11 H 24 ) density and speed-of-sound measurements in liquid phase have been reported along five isotherms at temperatures between (278 and 318) K. The density results have been obtained at pressure up to 60 MPa by means of a vibrating tube DMA 512 while speed-of-sound measurements for pressures up to 100 MPa. The speed-of-sound values have been measured by means of a double-path pulse-echo technique at three different operating frequencies. It has been chosen to repeat the measurements at different frequency values because of the observed discrepancies in the fly-time determination. A particular emphasis has been done to analyze these discrepancies, not directly explicable by traditional diffraction corrections. Indeed we have deduced that the source of differences is ascribable to a combination of sample speed-of-sound, of the signal frequency and to the geometrical configuration of the experiment, that affect the determination of the fly-time of the ultrasonic burst.

In an ion scattering spectroscopy experiment ions are directed onto a sample and the energy and charge state of the backscattered projectiles are determined. The kinetic energy used for the ions is in the range of a few kilo electron volts (keV). Ionized single atoms of almost any element can be used as the projectile. Ion scattering spectroscopy yields quantitative information which can include composition of the outermost layer as well as elemental concentration depth profiles and the crystal structure of the surface. Any sample can be investigated provided it can be handled in a vacuum chamber.

The collision dynamics of one Ag or Cu atom impinging on a Au12 cluster is investigated by means of DFT molecular dynamics. Our results show that the experimentally confirmed 2D to 3D transition of Au12-Au13 is mostly preserved by the resulting planar Au12Ag and Au12Cu minimum energy clusters, which is quite remarkable in view of the excess energy, well larger than the 2D-3D potential barrier height. The process is accompanied by a large sd hybridization and charge transfer from Au to Ag or Cu. The dynamics of the collision process mainly yields fusion of projectile and target, however scattering and cluster fragmentation also occur for large energies and large impact parameters. While Ag projectiles favor fragmentation, Cu favors scattering due to its smaller mass. The projectile size does not play a major role in favoring the fragmentation or scattering channels. By comparing our collision results with those obtained by an unbiased minimum energy search of 4483 Au12Ag and 4483 Au12Cu configurations obtained phenomenologically, we find that there is an extra bonus: without increase of computer time collisions yield the planar lower energy structures that are not feasible to obtain using semi-classical potentials. In fact, we conclude that phenomenological potentials do not even provide adequate seeds for the search of global energy minima for planar structures. Since the fabrication of nanoclusters is mainly achieved by synthesis or laser ablation, the set of local minima configurations we provide here, and their distribution as a function of energy, are more relevant than the global minimum to analyze experimental results obtained at finite temperatures, and is consistent with the dynamical coexistence of 2D and 3D liquid Au clusters conformations obtained previously.