Journal articles: 'Diffractive scattering processes'

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GAY DUCATI, M. B., and W. K. SAUTER. "GLUON PROPAGATOR IN DIFFRACTIVE SCATTERING." International Journal of Modern Physics A 21, no. 28n29 (November 20, 2006): 5861–74. http://dx.doi.org/10.1142/s0217751x06033945.

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In this work, we perform a comparison of the use of distinct gluon propagators with the experimental data in diffractive processes, pp elastic scattering and light meson photo-production. The gluon propagators are calculated through nonperturbative methods, being justified their use in this class of events, due to the smallness of the momentum transfer. Our results are not able to select the best choice for the modified gluon propagator among the analyzed ones. This shows that the application of this procedure in this class of high energy processes, although giving a reasonable fit to the experimental data, should be taken with same caution.

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IACOBUCCI, GIUSEPPE. "DIFFRACTIVE PHENOMENA." International Journal of Modern Physics A 17, no. 23 (September 20, 2002): 3204–19. http://dx.doi.org/10.1142/s0217751x02012697.

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The most recent theoretical and experimental results in the field of diffractive scattering are reviewed. A parallel between the two current theoretical approaches to diffraction, the DIS picture in the Breit frame and the dipole picture in the target frame, is given, accompanied by a description of the models to which the data are compared. A recent calculation of the rescattering corrections, which hints at the universality of the diffractive parton distribution functions, is presented. The concept of generalized parton distributions is discussed together with the first measurement of the processes which might give access to them. Particular emphasis is given to the HERA data, to motivate why hard diffraction in deep inelastic scattering is viewed as an unrivalled instrument to shed light on the still obscure aspects of hadronic interactions.

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Mücke, A., J. P. Rachen, Ralph Engel, R. J. Protheroe, and Todor Stanev. "Photohadronic Processes in Astrophysical Environments." Publications of the Astronomical Society of Australia 16, no. 2 (1999): 160–66. http://dx.doi.org/10.1071/as99160.

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AbstractWe discuss the first applications of our newly developed Monte Carlo event generator SOPHIA to multiparticle photoproduction of relativistic protons with thermal and power-law radiation fields. The measured total cross section is reproduced in terms of excitation and decay of baryon resonances, direct pion production, diffractive scattering, and non-diffractive multiparticle production. Non-diffractive multiparticle production is described using a string fragmentation model. We demonstrate that the widely used ‘Δ-approximation’ for the photoproduction cross section is reasonable only for a restricted set of astrophysical applications. The relevance of this result for cosmic ray propagation through the microwave background and hadronic models of active galactic nuclei and gamma-ray bursts is briefly discussed.

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Trzebiński, M. "Diffractive Physics at the LHC." Ukrainian Journal of Physics 64, no. 8 (September 18, 2019): 772. http://dx.doi.org/10.15407/ujpe64.8.772.

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Diffractive processes possible to be measured at the LHC are listed and briefly discussed. This includes soft (elastic scattering, exclusive meson pair production, diffractive bremsstrahlung) and hard (single and double Pomeron exchange jets, y +jet, W/Z, jet-gap-jet, exclusive jets) processes as well as Beyond Standard Model phenomena (anomalous gauge couplings, magnetic monopoles).

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ARISAWA, TETSUO. "HEAVY QUARK PRODUCTION BY HARD DIFFRACTIVE SCATTERING." Modern Physics Letters A 09, no. 03 (January 30, 1994): 247–57. http://dx.doi.org/10.1142/s0217732394000265.

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Heavy quark production in hard diffractive scattering is analyzed with evaluation of cross-sections and Monte-Carlo event generations. “Super hard” Pomeron, the existence of which was recently supported by the UA8 collaboration at CERN [Formula: see text] Collider [Formula: see text], is included by proposing a new method of determining Pomeron structures. Detection of (anti-)top quarks in the single diffractive processes is also mentioned.

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KUUSELA, MIKAEL, JERRY W. LÄMSÄ, ERIC MALMI, PETTERI MEHTÄLÄ, and RISTO ORAVA. "MULTIVARIATE TECHNIQUES FOR IDENTIFYING DIFFRACTIVE INTERACTIONS AT THE LHC." International Journal of Modern Physics A 25, no. 08 (March 30, 2010): 1615–47. http://dx.doi.org/10.1142/s0217751x10047920.

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Close to one half of the LHC events are expected to be due to elastic or inelastic diffractive scattering. Still, predictions based on extrapolations of experimental data at lower energies differ by large factors in estimating the relative rate of diffractive event categories at the LHC energies. By identifying diffractive events, detailed studies on proton structure can be carried out.The combined forward physics objects: rapidity gaps, forward multiplicity and transverse energy flows can be used to efficiently classify proton–proton collisions. Data samples recorded by the forward detectors, with a simple extension, will allow first estimates of the single diffractive (SD), double diffractive (DD), central diffractive (CD), and nondiffractive (ND) cross-sections. The approach, which uses the measurement of inelastic activity in forward and central detector systems, is complementary to the detection and measurement of leading beam-like protons.In this investigation, three different multivariate analysis approaches are assessed in classifying forward physics processes at the LHC. It is shown that with gene expression programming, neural networks and support vector machines, diffraction can be efficiently identified within a large sample of simulated proton–proton scattering events. The event characteristics are visualized by using the self-organizing map algorithm.

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Buchmüller, W., and A. Hebecker. "A parton model for diffractive processes in deep inelastic scattering." Physics Letters B 355, no. 3-4 (August 1995): 573–78. http://dx.doi.org/10.1016/0370-2693(95)00721-v.

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Anisovich, V. V., M. A. Matveev, and V. A. Nikonov. "Diffractive hadron production at ultrahigh energies." International Journal of Modern Physics A 30, no. 11 (April 16, 2015): 1550054. http://dx.doi.org/10.1142/s0217751x15500542.

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Diffractive production is considered in the ultrahigh energy region where pomeron exchange amplitudes are transformed into black disk ones due to rescattering corrections. The corresponding corrections in hadron reactions h1 + h3 → h1 + h2 + h3 with small momenta transferred [Formula: see text] are calculated in terms of the K-matrix technique modified for ultrahigh energies. Small values of the momenta transferred are crucial for introducing equations for amplitudes. The three-body equation for hadron diffractive production reaction h1 + h3 → h1 + h2 + h3 is written and solved precisely in the eikonal approach. In the black disk regime final state scattering processes do not change the shapes of amplitudes principally but dump amplitudes by a factor ~ ¼; initial state rescatterings result in additional factor ~ ½. In the resonant disk regime initial and final state scatterings damp strongly the production amplitude that corresponds to σ inel /σ tot → 0 at [Formula: see text] in this mode.

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Badran, R. I., and Dana Al-Masri. "Exploring diffractive features of elastic scattering of 6Li by different target nuclei at different energies." Canadian Journal of Physics 91, no. 4 (April 2013): 355–64. http://dx.doi.org/10.1139/cjp-2012-0466.

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The diffractive aspects of angular distribution have been investigated by analyzing the experimental data for a set of elastic scattering processes of 6Li by different target nuclei at different laboratory energies. The analysis of experimental data of angular distribution for elastic scattering process is performed using both Frahn–Venter and McIntyre models. The theoretical models can reasonably reproduce the general pattern of the data, thus allowing us to extract geometrical parameters from elastic scattering processes. It is found that interpretation of the diffraction features of the data is model-independent. The values of extracted parameters, from both models, are found to be comparable to each other and to those of others. The correlation between the total reaction cross section and the incident laboratory energy for each scattering is discernible and values of total reaction cross section are found to be comparable with those of others.

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Munier, Stéphane. "Diffractive patterns in deep-inelastic scattering and parton genealogy." EPJ Web of Conferences 192 (2018): 00008. http://dx.doi.org/10.1051/epjconf/201819200008.

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We report on our recent observation that the occurrence of diffractive patterns in the scattering of electrons off nuclei obeys the same law as the fluctuations of the height of genealogical trees in branching diffusion processes.

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STRANG, MICHAEL. "STATUS OF DIFFRACTIVE PHYSICS AT DØ RUN II." International Journal of Modern Physics A 20, no. 16 (June 30, 2005): 3762–64. http://dx.doi.org/10.1142/s0217751x05027540.

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The Forward Proton Detector (FPD) is a new sub-system of the DØ detector implemented for Run II at the Fermilab Tevatron which gives access to a wide range of diffractive scattering physics processes. This new detector is described and preliminary results from the diffractive program are presented.

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Hautmann, F., Z. Kunszt, and D. E. Soper. "Hard scattering factorization and light cone Hamiltonian approach to diffractive processes." Nuclear Physics B 563, no. 1-2 (December 1999): 153–99. http://dx.doi.org/10.1016/s0550-3213(99)00568-4.

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Badran, R. I., A. I. Istaiti, W. N. Mashaqbeh, and I. H. Al-Lehyani. "Regge pole analysis of elastic scattering of α particles by even isotopes of Ni target nuclei at incident energies above Coulomb barrier." International Journal of Modern Physics E 24, no. 11 (November 2015): 1550082. http://dx.doi.org/10.1142/s0218301315500822.

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Regge pole model is adopted to account for the angular distribution at backward angles for a set of elastic scattering processes of incident [Formula: see text]-particles by different isotopes of nickel ions, [Formula: see text]Ni, at different laboratory energies above Coulomb barrier. The reproduction of cross-sections at backward angles is preceded by an attempt to fit the experimental data at forward angles of the scattering. Three-parameter McIntyre model which is based on concept of strong absorption parametrization of the scattering matrix elements, has been employed to analyze and reproduce the experimental data of angular distribution of different elastic scattering reactions at forward angles. The three parameters extracted from McIntyre model analysis are employed as fixed entries in the fitting process of the full angle-range of angular distribution where another four free parameters are employed using the Regge pole model. Diffractive features observed in the angular distributions are studied. The Fresnel-type diffraction pattern is found dominant for all investigated elastic scatterings where Coulomb interaction is strong. The interaction radius of elastic scattering is found decreasing and the total cross-section increasing when the incident projectile energy increases. Moreover, the interaction radius and total reaction cross-section are found increasing with the increase in the size of target ion. Such diffractive behavior is consistent with the prescriptions of strong absorption model (SAM). Furthermore, the explanation of the diffractive features of studied elastic scattering reactions is model-independent. The Regge pole analysis reveals the existence of a pole which has its location, width, amplitude and phase angle exhibiting a common peak at energy of 24.1[Formula: see text]MeV with oscillatory behaviour at energies around this peak energy, for all elastic scattering of alpha particle on isotopes of Ni targets except that of [Formula: see text]Ni target which exhibits extra peaks for energy larger than 24.1[Formula: see text]MeV. We believe that the presence of poles is responsible for the oscillatory structure of the backward cross-sections. The variation of Regge pole parameters with both incident energy and size of target nucleus is illustrated.

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Anisovich, V. V., M. A. Matveev, and V. A. Nikonov. "Hadron diffractive production at ultrahigh energies and shadow effects." International Journal of Modern Physics A 31, no. 28n29 (October 19, 2016): 1645019. http://dx.doi.org/10.1142/s0217751x16450196.

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Shadow effects at collisions of hadrons with light nuclei at high energies were subject of scientific interest of V.N. Gribov, first, we mean his study of the hadron-deuteron scattering, see Sov. Phys. JETP 29, 483 (1969) [Zh. Eksp. Teor. Fiz. 56, 892 (1969)] and discovery of the reinforcement of shadowing due to inelastic diffractive rescatterings. It turns out that the similar effect exists on hadron level though at ultrahigh energies. Diffractive production is considered in the ultrahigh energy region where pomeron exchange amplitudes are transformed into black disk ones due to rescattering corrections. The corresponding corrections in hadron reactions [Formula: see text] with small momenta transferred ([Formula: see text], [Formula: see text]) are calculated in terms of the [Formula: see text]-matrix technique modified for ultrahigh energies. Small values of the momenta transferred are crucial for introducing equations for amplitudes. The three-body equation for hadron diffractive production reaction [Formula: see text] is written and solved precisely in the eikonal approach. In the black disk regime final state scattering processes do not change the shapes of amplitudes principally but dump amplitudes by a factor [Formula: see text]; initial state rescatterings result in additional factor [Formula: see text]. In the resonant disk regime initial and final state scatterings damp strongly the production amplitude that corresponds to [Formula: see text] at [Formula: see text] in this mode.

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BEREZHNOY, YU A., V. YU KORDA, and A. G. GAKH. "MATTER-DENSITY DISTRIBUTION IN THREE-NUCLEON NUCLEI AND THEIR DIFFRACTIVE INTERACTION WITH HEAVY NUCLEI." International Journal of Modern Physics E 18, no. 03 (March 2009): 665–74. http://dx.doi.org/10.1142/s0218301309012719.

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The nonrelativistic wave functions of 3 H and 3 He nuclei have been obtained on the basis of the experimentally measured charge form factors. The differential cross section of the elastic 3 He -nucleus scattering has been calculated with the help of the wave function derived. This cross section agrees with the experimental data on the elastic scattering of 3 He by 90 Zr , 120 Sn , and 208 Pb nuclei at 130 and 217 MeV. The integrated cross sections of various processes of 3 H and 3 He interaction with heavy nuclei have also been calculated.

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Anisovich, V. V., K. V. Nikonov, V. A. Nikonov, and J. Nyiri. "Proton–proton, pion–proton and pion–pion diffractive collisions at ultrahigh energies." International Journal of Modern Physics A 29, no. 15 (May 30, 2014): 1450096. http://dx.doi.org/10.1142/s0217751x14500961.

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The LHC energies are those at which the asymptotic regime in hadron–hadron diffractive collisions (pp, πp, ππ) might be switched on. Based on results of the Dakhno–Nikonov eikonal model which is a generalization of the Good–Walker eikonal approach for a continuous set of channels, we present a picture for transformation of the constituent quark mode to the black disk one. In the black disk mode [Formula: see text], we have a growth of the logarithm squared type for total and elastic cross-sections, σ tot ~ ln 2 s and σ el ~ ln 2 s and [Formula: see text]-scaling for diffractive scattering and diffractive dissociation of hadrons. The diffractive dissociation cross-section grows as σD ~ ln s, σDD ~ ln s, and their relative contribution tends to zero: σD/σ tot → 0, σDD/σ tot → 0. Asymptotic characteristics of diffractive and total cross-sections are universal, and this results in the asymptotical equality of cross-sections for all types of hadrons (the Gribov universality). The energy scale for switching on the asymptotic mode is estimated for different processes.

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Fiore, R., L. L. Jenkovszky, A. Lavorini, and V. K. Magas. "On the Interplay between Q2 and t Dependences in Exclusive Diffractive Production of Real Photons and Vector Mesons in ep Collisions." Ukrainian Journal of Physics 57, no. 12 (December 15, 2012): 1197. http://dx.doi.org/10.15407/ujpe57.12.1197.

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We show how the familiar phenomenological way of combining the Q2 (photon virtuality) and t (squared momentum transfer) dependences of the scattering amplitude in Deeply Virtual Compton Scattering (DVCS) [1, 2] and Vector Meson Production (VMP) [2] processes can be understood in an off-mass-shell generalization of dual amplitudes with Mandelstam analyticity [3]. By comparingdifferent approaches, we managed also to constrain the numerical values of the free parameters.

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Bylinkin, Alexander A., Dmitri E. Kharzeev, and Andrei A. Rostovtsev. "The origin of thermal component in the transverse momentum spectra in high energy hadronic processes." International Journal of Modern Physics E 23, no. 12 (December 2014): 1450083. http://dx.doi.org/10.1142/s0218301314500839.

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The transverse momentum spectra of hadrons produced in high energy collisions can be decomposed into two components: the exponential ("thermal") and the power ("hard") ones. Recently, the H1 Collaboration has discovered that the relative strength of these two components in Deep Inelastic Scattering (DIS) depends drastically upon the global structure of the event — namely, the exponential component is absent in the diffractive events characterized by a rapidity gap. We discuss the possible origin of this effect and speculate that it is linked to confinement. Specifically, we argue that the thermal component is due to the effective event horizon introduced by the confining string, in analogy to the Hawking–Unruh effect. In diffractive events, the t-channel exchange is color-singlet and there is no fragmenting string — so the thermal component is absent. The slope of the soft component of the hadron spectrum in this picture is determined by the saturation momentum that drives the deceleration in the color field, and thus the Hawking–Unruh temperature. We analyze the data on nondiffractive pp collisions and find that the slope of the thermal component of the hadron spectrum is indeed proportional to the saturation momentum.

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Lebiedowicz, Piotr, Otto Nachtmann, and Antoni Szczurek. "Tensor pomeron, vector odderon and diffractive production of meson and baryon pairs in proton-proton collisions." EPJ Web of Conferences 206 (2019): 06005. http://dx.doi.org/10.1051/epjconf/201920606005.

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We review some selected results of the tensor-pomeron and vectorodderon model of soft high-energy proton-proton scattering and central exclusive production of meson and baryon pairs in proton-proton collisions. We discuss the theoretical aspects of this approach and consider the phenomenological implications in a variety of processes at high energies, comparing to existing experimental data. We consider the diﬀractive dipion and dikaon production including the continuum and the dominant scalar and tensor resonance contributions as well as the photoproduction processes. The theoretical results are compared with existing CDF experimental data and predictions for planned or current LHC experiments, ALICE, ATLAS, CMS, LHCb are presented.

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Xie, Ya-Ping, and Xurong Chen. "Photoproduction of vector mesons in proton–proton ultraperipheral collisions at the CERN Large Hadron Collider." International Journal of Modern Physics A 33, no. 14n15 (May 28, 2018): 1850086. http://dx.doi.org/10.1142/s0217751x18500860.

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Photoproduction of vector mesons is computed with dipole model in proton–proton ultraperipheral collisions (UPCs) at the CERN Large Hadron Collider (LHC). The dipole model framework is employed in the calculations of vector mesons production in diffractive processes. Parameters of the bCGC model are refitted with the latest inclusive deep inelastic scattering experimental data. Employing the bCGC model and boosted Gaussian light-cone wave function for vector mesons, we obtain the prediction of rapidity distributions of [Formula: see text] and [Formula: see text] mesons in proton–proton ultraperipheral collisions at the LHC. The predictions give a good description of the experimental data of LHCb. Predictions of [Formula: see text] and [Formula: see text] mesons are also evaluated in this paper.

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Dremin, I. M. "Diffraction and unitarity." International Journal of Modern Physics A 31, no. 28n29 (October 19, 2016): 1645018. http://dx.doi.org/10.1142/s0217751x16450184.

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I begin with a tribute to V.N. Gribov and then come to a particular problem which would be of interest for him. His first paper on reggeology was devoted to elastic scatterings of hadrons. Here, using the unitarity relation in combination with experimental data about the elastic scattering in the diffraction cone, I show how the shape and the darkness of the interaction region of colliding protons change with the increase of their energies. In particular, the collisions become fully absorptive at small impact parameters at LHC energies that results in some special features of inelastic processes as well. The possible evolution with increasing energy of the shape from the dark core at the LHC to the fully transparent one at higher energies is discussed. It implies that the terminology of the black disk would be replaced by the black torus.

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Weckert, Edgar. "The potential of future light sources to explore the structure and function of matter." IUCrJ 2, no. 2 (February 3, 2015): 230–45. http://dx.doi.org/10.1107/s2052252514024269.

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Structural studies in general, and crystallography in particular, have benefited and still do benefit dramatically from the use of synchrotron radiation. Low-emittance storage rings of the third generation provide focused beams down to the micrometre range that are sufficiently intense for the investigation of weakly scattering crystals down to the size of several micrometres. Even though the coherent fraction of these sources is below 1%, a number of new imaging techniques have been developed to exploit the partially coherent radiation. However, many techniques in nanoscience are limited by this rather small coherent fraction. On the one hand, this restriction limits the ability to study the structure and dynamics of non-crystalline materials by methods that depend on the coherence properties of the beam, like coherent diffractive imaging and X-ray correlation spectroscopy. On the other hand, the flux in an ultra-small diffraction-limited focus is limited as well for the same reason. Meanwhile, new storage rings with more advanced lattice designs are under construction or under consideration, which will have significantly smaller emittances. These sources are targeted towards the diffraction limit in the X-ray regime and will provide roughly one to two orders of magnitude higher spectral brightness and coherence. They will be especially suited to experiments exploiting the coherence properties of the beams and to ultra-small focal spot sizes in the regime of several nanometres. Although the length of individual X-ray pulses at a storage-ring source is of the order of 100 ps, which is sufficiently short to track structural changes of larger groups, faster processes as they occur during vision or photosynthesis, for example, are not accessible in all details under these conditions. Linear accelerator (linac) driven free-electron laser (FEL) sources with extremely short and intense pulses of very high coherence circumvent some of the limitations of present-day storage-ring sources. It has been demonstrated that their individual pulses are short enough to outrun radiation damage for single-pulse exposures. These ultra-short pulses also enable time-resolved studies 1000 times faster than at standard storage-ring sources. Developments are ongoing at various places for a totally new type of X-ray source combining a linac with a storage ring. These energy-recovery linacs promise to provide pulses almost as short as a FEL, with brilliances and multi-user capabilities comparable with a diffraction-limited storage ring. Altogether, these new X-ray source developments will provide smaller and more intense X-ray beams with a considerably higher coherent fraction, enabling a broad spectrum of new techniques for studying the structure of crystalline and non-crystalline states of matter at atomic length scales. In addition, the short X-ray pulses of FELs will enable the study of fast atomic dynamics and non-equilibrium states of matter.

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Weckert, Edgar. "The potential of future light sources to explore the structure and function of matter." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C31. http://dx.doi.org/10.1107/s2053273314099689.

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Structural studies in general and in particular in crystallography have benefited and still do benefit dramatically from the use of synchrotron radiation. Its tuneability is mandatory for multi or single anomalous diffraction experiments, still one of the main methods for solving new crystal structures. Its tuneability is also a key for spectroscopy techniques for the determination of the local atomic environment around and the oxidation state of an absorbing atom. These techniques are powerful tools e.g. in chemistry to study reactions, and can be applied not only to crystalline matter. Low emittance storage rings of the third generation with their highly brilliant X-ray beams enable us to focus beams down to the micrometer range intense enough for the investigation of weakly scattering crystals down to the size of several micrometers. Considering these highly intense beams, if it comes to structural studies using X-ray, what are still the limitations of the most modern storage ring sources? The length of individual X-ray pulses is in the order of 100 ps, which is sufficient to trace structural changes of larger groups or the diffusion of atoms over larger atomic distances. However, fast processes as they occur e.g. during vision or photosynthesis are not accessible by these means. Also the coherent fraction of the radiation of present day storage rings in the X-ray regime is rather low (i.g. < 1 %). This limits on one hand our ability to study the structure and dynamic of non-crystalline materials by methods exploiting the coherence properties of the beam like coherent diffractive imaging and X-ray correlation spectroscopy, respectively. On the other hand the flux in an ultra small diffraction-limited focus is limited as well. Upcoming linac driven free electron laser (FEL) sources with extremely short (sub 100 fs) and intense pulse (~10^12 ph) of very high coherence circumvent some of the limitations of present day storage rings. It has been demonstrated that their individual pulses are short enough to outrun radiation damage for single pulse exposures. First structures from sub micrometer crystals using an X-ray FEL (LCLS, Stanford) have already been published. These ultra short pulses also enable time resolved studies 1000 times faster than at standard storage ring sources. Meanwhile new storage rings with more aggressive lattice designs are under construction or under consideration with significantly smaller emittances. These sources target towards the diffraction limit in the X-ray regime and will provide roughly one to two orders of magnitude higher brilliance and coherence. They will be especially suited to those experiments exploiting the coherence properties of the beams and to ultra small focal spot sizes in the several nm regime. Developments at various places are ongoing for a totally new type of X-ray source combining a linac with a storage ring. This so called energy recovery linacs (ERL) promise to provide pulses almost as short as at an FEL with brilliances and multi-user capabilities comparable to a diffraction limited storage ring. The contribution will try to give an overview of the stage of development of the various source projects and their possible impact on structural studies in future.

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Wang, Z. L. "Diffraction theory of phonon-scattered electrons." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 788–89. http://dx.doi.org/10.1017/s0424820100088257.

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Electron-phonon interactions are inelastic scattering processes in high-energy electron diffraction, and are responsible for thermal diffuse scattering (TDS). The atomic thermal vibrations introduce a small time-dependent perturbation to the crystal potential(1)where is the displacement of the atom (at position within the hth unit cell (position R(h)) from its equilibrium position,(2)

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Chen, Jie, Xin Zhou, Xing Bai, Cong Li, Zhao Xu, and Yang Ni. "Equivalence analysis of highly scattering process and double random phase encryption process." Acta Physica Sinica 70, no. 13 (2021): 134201. http://dx.doi.org/10.7498/aps.70.20201903.

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The scattering system through a highly scattering thin layer only affects the amplitude and phase distribution of incident light wave, but does not lead the total energy to be attenuated. This process can be regarded as a process that light wave is encoded by the scattering medium, which is similar to a double random phase encryption system. In this paper, firstly, it is proved that the distribution characteristics of speckle generated by the light wave carrying the target information through a strongly scattering thin layer are highly similar to the distribution characteristics of cyphertext obtained by the double random phase encryption system encrypting the same plaintext target. Therefore, the scattering system is seen as a double random phase encryption system, and the two random phase keys corresponding to the scattering system are calculated accurately by using the phase recovery algorithm. At the same time, it is proved that these two key boards can successfully reconstruct the original images corresponding to any other speckles obtained by the scattering system. Finally, a cyphertext-only attack method to attack a scattering system through a highly scattering thin layer is used to further prove the equivalence of two key boards and the good results are obtained. Since imaging through a scattering medium is an extremely complicated process, we actually simplify the corresponding process ideally. It should be noted that the equivalent system means that the incident-surface-to-exit-surface of scattering medium is equivalent to the incident-surface-to-exit-surface of DRPE system. However, in the actual process, there are still two diffraction processes: one is the diffraction process from the object to the incident surface and the other is the diffraction process from the output surface to the receiving surface. These two diffraction processes will cause the incident image and the output image of scattering medium to have a certain diffraction effect. We believe that under ideal conditions, due to the equivalence between the thin-layer strong scattering system and the DRPE system, theoretically all pure ciphertext attack methods applicable to the DRPE system can be applied to the speckle recovery of the thin-layer strong scattering system. In the future, it is possible to develop more methods of using system equivalence to crack the scattered light field. We hope this article can provide a new idea for scattering imaging.

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Wang, Z. L. "Coupled thermal diffuse-atomic inner shell scattering in electron diffraction." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 994–95. http://dx.doi.org/10.1017/s042482010017270x.

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In electron diffraction patterns, diffuse scattering at high angles is primarily generated by phonon, or thermal diffuse, scattering (TDS). Techniques were introduced to acquire the electron energy-loss spectra (EELS) of high-angle thermal-diffuse-scattered electrons (TDS-EELS) in a transmission electron microscope (TEM). With regards to the scattering mechanism, the TDS-EELS core ionization edge intensity was believed to be generated primarily by TDS - single electron, double-inelastic electron scattering processes. It was concluded from experimental data that the signal from coupled phonon - atomic inner shell excitations is stronger than that from atomic inner shell excitation alone. A formal dynamical theory is presented in this paper to illustrate the theoretical basis of the experimental observations. The theory can be applied to calculate the diffraction patterns of inelastically double-scattered electrons and the signal intensity observed in TDS-EELS.TDS is actually a statistically averaged, quasi-elastic scattering of the electrons by the crystal lattice of different thermal vibration configurations.

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Wang, L., J. Liu, and J. M. Cowley. "Zero-Loss Energy Filtered REM and RHEED Observations on Rutile (110) Surface." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 968–69. http://dx.doi.org/10.1017/s0424820100150678.

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In reflection electron microscopy (REM), the surface reflection electrons undergo both elastic and inelastic scattering within a crystal. The dominant inelastic processes are phonon scattering, valence electron excitation, bulk and surface plasmon excitation and combinations of these processes. Multiple inelastic scattering processes are also probable as the mean traveling distance of surface reflection electrons is about 10 to 100 nm. In reflection high energy electron diffraction pattern (RHEED), 50% to 90% of the electrons contributing to surface reflection spots used for imaging have suffered energy loss of more than 10 eV, thus the main limitation on REM image resolution is due to the chromatic aberration effects given by the energy spread from inelastic scattering. An energy filter fitted inside a TEM microscope can remove most of the inelastic scattering contribution and so improve the contrast and resolution. Oxygen-annealed rutile (001), (100) and (110) surfaces were previously studied by REM and RHEED techniques without energy filtering.

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Yan, Sihan, Wei Wang, Cheng Wang, Limin Chen, Xiaoqian Ai, Qiyun Xie, and Guofeng Cheng. "Anharmonic phonon scattering study in MnPS₃ crystal by Raman spectroscopy." Applied Physics Letters 121, no. 3 (July 18, 2022): 032203. http://dx.doi.org/10.1063/5.0096814.

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Phonons play a vital role in lattice dynamics, so a better understanding of anharmonic phonon scattering in van der Waals material MnPS3 is of great significance for its potential applications. Here, we employed Raman spectrum, in situ x-ray diffraction, and first-principles calculations for detailed research. The volume thermal expansion coefficient of MnPS3 was reported. Through the symmetric phonon scattering model, it is confirmed that cubic phonon processes play a major role in P2, P3, P4, and P5 peaks, while quartic phonon processes play an indispensable role in most peaks. The covalent bond was found to be more susceptible to anharmonic phonon scattering than ionic bonds, which is reflected in the wavenumber redshift. Moreover, asymmetric phonon scattering channels also play a meaningful role. Different cubic phonon scattering channels greatly influence the fitting results, and various quartic phonon scattering channels are diverse in highly nonlinear linewidth broadening.

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Rez, Peter. "Schemes to determine the crystal potential under dynamical conditions using voltage variation." Acta Crystallographica Section A Foundations of Crystallography 55, no. 2 (March 1, 1999): 160–67. http://dx.doi.org/10.1107/s0108767398008630.

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Charge densities and crystal structures can be determined routinely from X-ray diffraction as X-ray scattering is relatively weak and single scattering can be assumed. The strong dynamical diffraction of high-energy electrons has prevented electron diffraction from being used in the same way. Dynamical diffraction describes both the propagation of the Bragg diffracted wave in the crystal and the scattering by the crystal potential. The balance between these two processes changes as a function of voltage due to relativistic effects. The difference in diffracted intensities recorded at two voltages is shown to be directly proportional to the crystal potential. This is confirmed by calculations using first-order perturbation theory which show negligible differences compared to exact calculation. It should therefore be possible to use differences in intensity measured as a function of voltage to determine the crystal potential directly. If the full complex wave function is available, then there is a particularly simple procedure to recover the potential, even under dynamical conditions.

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30

Niggl, L., and Max Maier. "Gain-guided modes in stimulated scattering processes with diffraction-free pump beams." Optics Communications 154, no. 1-3 (August 1998): 65–69. http://dx.doi.org/10.1016/s0030-4018(98)00305-8.

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Pennycook, S. J. "Diffraction Channeling and the Production of Secondary Excitation." Microscopy and Microanalysis 5, S2 (August 1999): 688–89. http://dx.doi.org/10.1017/s1431927600016767.

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The pivotal role played by Archie Howie in the development of many areas of electron microscopy is universary acknowledged.Here I would like to highlight his contribution to the quantitative description of secondary excitations, which was an important influence on the development of Z-contrast imaging in zone-axis crystals. Secondary excitations are those such as x-ray emission which occur following a primary scattering event, in this case excitation of inner shell electrons. The first important concept to be realized by Archie was that dynamical diffraction and channeling are different manifestations of the same physical effect, namely, the multiple scattering of electrons within a crystal. Second was the realization that processes which are localized within the unit cell will show a dependence on diffraction conditions, such as incident beam orientation, and could therefore be described quantitatively using dynamical diffraction theory. Precisely the same theory was used to describe the orientation dependence of cathodoluminescenceThe development of the STEM for high resolution imaging was of course due primarily to Crewe and coworkers, with an annular detector to allow efficient detection of elastic scattering over a wide angular range.

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Kopecký, Miloš, Edoardo Busetto, and Andrea Lausi. "Reconstruction of diffraction patterns by using the Helmholz–Kirchhoff integral theorem." Journal of Applied Crystallography 36, no. 6 (November 15, 2003): 1368–71. http://dx.doi.org/10.1107/s002188980302020x.

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A new method to obtain three-dimensional information on atomic arrangement from a monochromatic Laue pattern based on the Helmholz–Kirchhoff integral theorem is presented and experimentally proved by applying the algorithm to the thermal diffuse scattering from a single crystal. The advantage given by the possibility of collecting all the required data on a position-sensitive detector in one shot opens new perspectives for studies of fast physical or chemical processes in three dimensions. The reduced exposure time can also avoid radiation damage of organic specimens, and, in conjunction with an ultra-bright beam from the next generation of X-ray free-electron lasers, makes the method suitable for structural studies with individual atomic clusters. This approach can also be used, by observing the thermal diffuse scattering or order diffuse scattering from both non-crystalline samples and `imperfect' crystals, for the investigation of short-range ordered arrangements of atoms.

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33

Barker, John George, Jeremy C. Cook, Jean Philippe Chabot, Steven R. Kline, Zhenhuan Zhang, and Cedric Gagnon. "Mitigating background caused by extraneous scattering in small-angle neutron scattering instrument design." Journal of Applied Crystallography 54, no. 2 (March 3, 2021): 461–72. http://dx.doi.org/10.1107/s1600576721001084.

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Measurements, calculations and design ideas to mitigate background caused by extraneous scattering in small-angle neutron scattering (SANS) instruments are presented. Scattering includes processes such as incoherent scattering, inelastic scattering and Bragg diffraction. Three primary sources of this type of background are investigated: the beam stop located in front of the detector, the inside lining of the detector vessel and the environment surrounding the sample. SANS measurements were made where materials with different albedos were placed in all three locations. Additional measurements of the angle-dependent scattering over the angular range of 0.7π–0.95π rad were completed on 16 different shielding materials at five wavelengths. The data were extrapolated to cover scattering angles from π/2 to π rad in order to estimate the materials' albedos. Modifications to existing SANS instruments and sample environments to mitigate extraneous scattering from surfaces are discussed.

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KORTE, UWE. "INTERPRETATION OF REFLECTION HIGH ENERGY ELECTRON DIFFRACTION FROM DISORDERED SURFACES: DYNAMICAL THEORY AND ITS APPLICATION TO THE EXPERIMENT." Surface Review and Letters 06, no. 03n04 (June 1999): 461–95. http://dx.doi.org/10.1142/s0218625x99000469.

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Reflection high energy electron diffraction (RHEED) is one of the few surface science techniques that are applied in a fabrication process, namely to monitor the epitaxial growth of ultrathin films and advanced materials. In spite of this technological relevance the multiple scattering nature of the involved scattering processes has hindered the quantitative interpretation of RHEED in the case of real, i.e. imperfect, surfaces for a long time. This article reviews recent progress in the understanding of RHEED from surfaces exhibiting various types of disorder. It concentrates on a multiple scattering formalism — based on perturbation theory with the nonperiodic part of the structure as perturbation — that allows the computation and interpretation of RHEED from real systems. The validity regime of the approach is discussed. We demonstrate the potential of the method by its application to the quantitative interpretation of experimental data. The range of treated problems comprises occupational disorder, intensity oscillations, structure of disordered metal/adsorbate systems, diffuse scattering from adatoms, Kikuchi scattering and phonon scattering.

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35

King, A., N. Guignot, L. Henry, G. Morard, A. Clark, Y. Le Godec, and J. P. Itié. "Combined angular and energy dispersive diffraction: optimized data acquisition, normalization and reduction." Journal of Applied Crystallography 55, no. 2 (February 10, 2022): 218–27. http://dx.doi.org/10.1107/s1600576722000322.

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Combined angular and energy dispersive diffraction is particularly well suited to experiments at high pressures in large-volume presses, and to the study of liquid or amorphous systems. This work describes the data acquisition, correction and reduction approach developed at the PSICHE beamline of the SOLEIL synchrotron. The measured data were normalized for both the scattering volume and the effective incident energy spectrum. By optimizing the acquisition strategy, the measurement time and radiation dose are greatly reduced. The correction and reduction protocol outputs normalized scattering profiles that are suitable for pair distribution function or liquid structure analysis. These processes are demostrated with examples from a number of real experimental data sets.

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Nurislamova, G. V., Rinat K. Islamgaliev, and Ruslan Valiev. "Microstructure and Mechanical Properties of Pure Nickel Processed by Severe Plastic Deformation." Materials Science Forum 503-504 (January 2006): 579–84. http://dx.doi.org/10.4028/www.scientific.net/msf.503-504.579.

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Microstructure and mechanical properties of pure nickel processed by high pressure torsion (HPT) and equal channel angular pressing (ECAP) have been investigated in the present paper. The uniformity of microstructure and misorientation angles in the SPD samples were studied using transmission electron microscopy and electron back scattering diffraction. Microstructural requirements for achivement of high strength and ductility in SPD metals are discussed.

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VALERI, SERGIO, and ALESSANDRO di BONA. "MODULATED ELECTRON EMISSION BY SCATTERING-INTERFERENCE OF PRIMARY ELECTRONS." Surface Review and Letters 04, no. 01 (February 1997): 141–60. http://dx.doi.org/10.1142/s0218625x9700016x.

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We review the effects of scattering-interference of the primary, exciting beam on the electron emission from ordered atomic arrays. The yield of elastically and inelastically backscattered electrons, Auger electrons and secondary electrons shows a marked dependence on the incidence angle of primary electrons. Both the similarity and the relative importance of processes experienced by incident and excident electrons are discussed. We also present recent studies of electron focusing and defocusing along atomic chains. The interplay between these two processes determines the in-depth profile of the primary electron intensity anisotropy. Finally, the potential for surface-structural studies and limits for quantitative analysis are discussed, in comparison with the Auger electron diffraction (AED) and photoelectron diffraction (PD) techniques.

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38

Reimer, L., and I. Fromm. "Electron spectroscopic diffraction at (111) silicon foils." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 382–83. http://dx.doi.org/10.1017/s0424820100153889.

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An electron diffraction pattern (EDP) consists of an overlap of patterns of all energy losses in the electron energy-loss spectrum (EELS). Electron spectroscopic diffraction (ESD) in an energy filtering electron microscope (EFEM) allows to separate the contributions of different energy losses to the unfiltered diagram observed in conventional TEM. We report about diffraction experiments with a Zeiss EM902 on (111) silicon foils which show how the EDP of single-crystal foils changes with increasing energy loss and foil thickness. An EDP normally contains the Bragg spots, diffuse streaks by electron-phonon scattering, excess and defect Kikuchi lines when the number of electrons striking the lattice planes is different from opposite sites, a system of excess (bright) Kikuchi bands with an intensity proportional to the probability ψψ⋆ of the Bloch wave field at the nuclei, and defect Ki-kuchi bands when the number of diffusely scattered electrons is equal on both sides of the lattice plane and the intensity becomes proportional to ΣIg.EDPs of thin foils show an increase of contrast of the Bragg spots and the thermal diffuse streaks when comparing an unfiltered (Fig.1a) and zero-loss filtered EDP (Fig.1b). Because the streaks are caused by elastic scattering, they can not be ob served with the plasmon loss (Fig.1c). Bragg spots are also observed at higher energy losses because all delocalized inelastic scattering processes with energy losses less a few hundred eV show intraband transitions which preserve the type of excited Bloch waves.

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39

Dabas, Dr Seema. "Neutron Scattering in Nanotubes." International Journal for Research in Applied Science and Engineering Technology 10, no. 5 (May 31, 2022): 3710–13. http://dx.doi.org/10.22214/ijraset.2022.43147.

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Abstract: Neutron scattering has got numerous applications in various fields of research like material research, crystallography etc. Thermal neutron scattering in randomly un-aligned multi walled carbon nanotubes is based on its anisotropic frequency distribution function. This frequency distribution function is obtained using a dynamical model which includes the presence of both the surface modes and intertube coupling. Experimentally measured values of specific heat for randomly un-aligned multi walled carbon nanotubes has been studied to detect the phonon frequency distribution function. Elastic scattering is used for analyzing structures. Inelastic scattering is applied for the study of atomic vibrations. The dynamical model has been used to find the scattering values. Both scattering values are calculated and compared. It was concluded that the difference in their values is large. This difference would affect the transport processes in randomly un-aligned multi walled carbon nanotubes Keywords: Specific heat, Elastic scattering, Inelastic scattering, Neutron Diffraction, Frequency Distribution Function

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40

Simeone, David, Dominique Gosset, and Gianguido Baldinozzi. "A preferred orientation correction to describe a fiber texture under glancing incidence." Journal of Applied Crystallography 46, no. 1 (December 21, 2012): 93–98. http://dx.doi.org/10.1107/s0021889812045736.

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Much work is nowadays being devoted to the characterization of the structure and the microstructure of thin films and mesoporous materials. Different physical and chemical processes used to elaborate these thin films often induce a fiber texture in these materials. The X-ray glancing-incidence technique appears to be a useful tool for collecting diffraction patterns of thin films while avoiding the peaks of the substrate. However, the scattering vector in this asymmetric scattering geometry is not perpendicular to the surface of the sample. This point implies that the correction developed to model the effects of a fiber texture in Bragg–Brentano geometry, where the scattering vector is always normal to the surface of the sample, cannot be applied in glancing incidence. This work presents a procedure to correct the preferred orientation due to this fiber texture in asymmetric scattering geometry and then in glancing incidence. By an example, it is proved that this correction of the fiber texture is efficient. The main point of interest regarding this correction is that only a few parameters are needed to handle the effect of the fiber texture on the diffraction patterns collected in asymmetric scattering geometry and then under glancing incidence.

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41

Yang, Ping, Li Meng, Yisong Hu, Zude Zhao, and Xueping Ren. "ANALYSIS OF DEFORMATION PROCESSES OF MAGNESIUM ALLOY AT ELEVATED TEMPERATURES BY ORIENTATION MAPPING." Image Analysis & Stereology 23, no. 1 (May 3, 2011): 53. http://dx.doi.org/10.5566/ias.v23.p53-61.

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Orientation mapping based on electron back scattering diffraction technique was applied to reveal the distributions of disorientations and rotation axes of grains caused by plastic slip and twinning during channel die compression in magnesium alloy ZA31. In addition, the orientations of dynamically recrystallized grains and deformed grains were separated and compared with respect to their initial textures. The relationship of strain and {1012} twin amount was determined quantitatively by referring to twin orientations. The reasons leading to the observed phenomena are analyzed and discussed.

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42

Spence, J. C. H. "XFELs for structure and dynamics in biology." IUCrJ 4, no. 4 (May 10, 2017): 322–39. http://dx.doi.org/10.1107/s2052252517005760.

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The development and application of the free-electron X-ray laser (XFEL) to structure and dynamics in biology since its inception in 2009 are reviewed. The research opportunities which result from the ability to outrun most radiation-damage effects are outlined, and some grand challenges are suggested. By avoiding the need to cool samples to minimize damage, the XFEL has permitted atomic resolution imaging of molecular processes on the 100 fs timescale under near-physiological conditions and in the correct thermal bath in which molecular machines operate. Radiation damage, comparisons of XFEL and synchrotron work, single-particle diffraction, fast solution scattering, pump–probe studies on photosensitive proteins, mix-and-inject experiments, caged molecules, pH jump and other reaction-initiation methods, and the study of molecular machines are all discussed. Sample-delivery methods and data-analysis algorithms for the various modes, from serial femtosecond crystallography to fast solution scattering, fluctuation X-ray scattering, mixing jet experiments and single-particle diffraction, are also reviewed.

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43

Dremin, I. M. "The Profile of Inelastic Collisions from Elastic Scattering Data." Advances in High Energy Physics 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/912743.

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Using the unitarity relation in combination with experimental data about the elastic scattering in the diffraction cone, it is shown how the shape and the darkness of the inelastic interaction region of colliding protons change with increase of their energies. In particular, the collisions become fully absorptive at small impact parameters at LHC energies that results in some special features of inelastic processes. Possible evolution of this shape with the dark core at the LHC to the fully transparent one at higher energies is discussed that implies that the terminology of the black disk would be replaced by the black toroid. The approach to asymptotics is disputed. The ratio of the real to imaginary parts of the nonforward elastic scattering amplitude is briefly discussed. All the conclusions are only obtained in the framework of the indubitable unitarity condition using experimental data about the elastic scattering of protons in the diffraction cone without any reference to quantum chromodynamics (QCD) or phenomenological approaches.

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Sung, Daeho, Daewoong Nam, Myong-jin Kim, Seonghan Kim, Kyung Sook Kim, Sang-Youn Park, Sun Min Hwang, et al. "Single-Shot Coherent X-ray Imaging Instrument at PAL-XFEL." Applied Sciences 11, no. 11 (May 30, 2021): 5082. http://dx.doi.org/10.3390/app11115082.

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We developed a single-shot coherent X-ray imaging instrument at the hard X-ray beamline of the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL). This experimental platform was established to conduct a variety of XFEL experiments, including coherent diffraction imaging (CDI), X-ray photon correlation spectroscopy (XPCS), and coherent X-ray scattering (CXS). Based on the forward-scattering geometry, this instrument utilizes a fixed-target method for sample delivery. It is well optimized for single-shot-based experiments in which one expects to observe the ultrafast phenomena of nanoparticles at picosecond temporal and nanometer spatial resolutions. In this paper, we introduce a single-shot coherent X-ray imaging instrument and report pump–probe coherent diffraction imaging (PPCDI) of Ag nanoparticles as an example of its applications.

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Thorkildsen, Gunnar, Helge B. Larsen, Edgar Weckert, and Dag Semmingsen. "Three-beam X-ray diffraction – profile analysis." Journal of Applied Crystallography 36, no. 6 (November 15, 2003): 1324–33. http://dx.doi.org/10.1107/s0021889803016145.

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An original functional description of the intensity perturbation of the two-beam diffracted power caused by an interfering three-beam interaction has been developed. By using this approach in the analysis of measured three-beam profiles of α-oxalic acid dihydrate, parameters related to the Darwin mosaic model are refined. The final results indicate an anisotropy in both the mean domain size, measured along the secondary beam, and the block orientation, measured as the angular spread in the location of the three-beam point. The presented method relies on a procedure for merging the contributions to the perturbation originating from dynamical (coherent) and kinematical (incoherent) scattering processes.

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He, Y., L. M. Yu, P. A. Thiry, and R. Caudano. "Negative Ion Resonance Evidenced by Vibrationally Resolved Electron Diffraction On the H/Si(111) Surface." Surface Review and Letters 05, no. 01 (February 1998): 63–67. http://dx.doi.org/10.1142/s0218625x98000141.

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The surface vibrations of H-terminated Si(111) are investigated by high resolution electron energy loss spectroscopy (HREELS). Clear evidence is obtained for reassigning the electron resonant scattering from a surface resonance to a negative ion resonance mechanism. Since the electrons emitted from the trapping states show characteristic angular diffraction patterns realated with the geometric and vibrational symmetries of the surface, we suggest the possibility of using this system to investigate vibrationally resolved electron diffraction processes.

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MA, DECAI, BIAO WANG, RUI WANG, HAI WANG, HONGCHENG LIU, and QINGKUN LI. "INFLUENCE OF POST-TREATMENT ON OPTICAL PROPERTIES OF Sc:Ce:Cu:LiNbO3 CRYSTALS." Modern Physics Letters B 21, no. 04 (February 10, 2007): 207–14. http://dx.doi.org/10.1142/s0217984907012499.

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The congruent Sc(3 mol%):Ce:Cu:LiNbO 3 single crystals were grown by the Czochralski method and three kinds of different samples were prepared by proper reduction or oxidation post-treatment processes. The extrinsic defect structures of samples were determined by infrared transmittance spectra. Two-wave coupling and light induced scattering experiments were used to measure the photorefractive properties. It is found that the reduction treatment made erasure time and diffraction efficiency decrease, but light-induced scattering resistance increase; the inverse case occurred with oxidation treatment. Analysis indicated that photoconductivity change was responsible for photorefractive properties.

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Fukazawa, Hiroshi, Shinji Mae, and Susumu Ikeda. "Raman scattering and neutron-diffraction studies of fresh ice and Antarctic ice." Annals of Glaciology 31 (2000): 247–51. http://dx.doi.org/10.3189/172756400781820426.

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AbstractIn order to investigate the temperature dependence of vibrational spectra of ice, we measured the Raman spectra of artificial ice Ih in the temperature range 198–270 K. The frequency of translational lattice vibrations decreases with increases in the measurement temperature, and the rate of decrease discontinuously changes at 237 K. The discontinuous change of the rate of decrease is consistent with the phase transition from a proton-disordered arrangement to a proton-ordered arrangement at the ice temperature Ti = 237 K in polar ice sheets, as proposed by Fukazawa and others (1998b). We then compared the Raman spectra of translational lattice vibrations in ice Ih and Antarctic ice and examined the possible effects of the phase transition on the geophysical properties of Antarctic ice. We also report preliminary results of the neutron powder diffraction of Dome Fuji (DF) Antarctic ice, and discuss arrangements of protons in DF ice.

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Pérez-Ramírez, J. G., R. Pérez, and M. José-Yacamán. "On the characterization of superstructures in HREM images of YBa2Cu3O7-x using image processing techniques." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 860–61. http://dx.doi.org/10.1017/s0424820100106363.

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Electron diffraction patterns obtained from samples of YBa2Cu3O7-x (0≤x≤1) compound shows besides the normal tetragonal or orthorhombic structures also superstructure reflections corresponding to various diffuse scattering effects which are attributed to the ordering of the oxigen vacancies existing in the samples. The diffuse scattering was not always the same in appearance. It was often not localized at position but appeared as lines with uniform intensity connecting neighbouring diffraction spots. Optical diffraction patterns from HREM images of this compound have indicated the presence of a superstructure with a period equal to the double periodicity obtained under [001] zone axis diffraction conditions. In this work we studied HREM images of twin and matrix crystals adjacent to the commonly found (110) twin boundaries in the superconducting compound. Image processing techniques have been applied to these images and the results indicate also the presence of a superstructure which can clearly be seen in the enhanced processed images.

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BEREZHNOY, YU A., V. YU. KORDA, and A. G. GAKH. "MATTER-DENSITY DISTRIBUTION IN DEUTERON AND DIFFRACTION DEUTERON-NUCLEUS INTERACTION." International Journal of Modern Physics E 14, no. 07 (October 2005): 1073–85. http://dx.doi.org/10.1142/s0218301305003697.

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We obtained a nonrelativistic deuteron wave function that accounts for the D-state and has correct asymptotic behavior. This was achieved on the basis of the experimentally measured charge and quadrupole deuteron form factors. The differential cross section of the elastic deuteron-nucleus scattering has been calculated by using this wave function. These predictions agree with the experimental data at the energy of 110 MeV. The integrated cross sections of the various processes involving the deuteron-nucleus interactions were also calculated.

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Journal articles on the topic 'Diffractive scattering processes'

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