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We perform numerical simulations for the dynamics of a chain of weakly coupled particles, and consider the process of occupation of cells in phase space, in the spirit of paper [1]. A different behaviour is exhibited as the coupling constant is changed. It is discussed whether such a dynamical behaviour is compatible with the Tsallis statistics. [ABSTRACT FROM AUTHOR]

Ions with energies above the plasma ion temperature (also called super thermal, hot or energetic particles - EP) are utilized in laboratory experiments as a plasma heat source to compensate for energy loss. Sources for super thermal ions are direct injection via neutral beams, RF heating and fusion reactions. Being super thermal, ions have the potential to induce instabilities of a certain class of magnetohydrodynamics (MHD) cavity modes, in particular, various Alfvén and Alfvénacoustic Eigenmodes. It is an area where ideal MHD and kinetic theories can be tested with great accuracy. This paper touches upon key motivations to study the energetic ion interactions with MHD modes. One is the possibility of controlling the heating channel of present and future tokamak reactors via EP transport. In some extreme circumstances, uncontrolled instabilities led to vessel wall damages. This paper reviews some experimental and theoretical advances and the developments of the predictive tools in the area of EP wave interactions. Some recent important results and challenges are discussed. Many predicted instabilities pose a challenge for ITER, where the alpha-particle population is likely to excite various modes. [ABSTRACT FROM AUTHOR]

Ernest Rutherford's discovery of the atomic nucleus is a landmark in science history and a century later the story behind it is well known. Generations have read of Ernest Marsden's scattering experiments and Rutherford's astonishment at the results, followed by the older man's long retreat into contemplation until the day he could announce that he "knew what the atom looked like". This paper, a commemorative presentation, reconsiders that story. The contemporaneous record is weak in some respects, indicating some need for caution in accepting details and prompting questions about why those involved did not write about it at the time. Further, the addition as context of Rutherford's ambitious program of action in atomic research at Manchester-which transformed his department-diminishes the folkloric character of the story and switches the emphasis to Rutherford's personality. In his determination to penetrate the secrets of the atom this "battleship of physics" left little to chance. [ABSTRACT FROM AUTHOR]

This paper starts from a brief overview of theoretical studies of high-gradient accelerating structures at the University of Maryland. The rest of the paper is devoted to the analysis of ion bombardment of small protrusions in such structures. First, this problem is studied analytically. Then, some results of particle-in-cell simulations performed with the use of code WARP are presented and discussed. [ABSTRACT FROM AUTHOR]

In 1958, Baranger published three papers in which he established a general theory of the broadening of spectral lines by perturbing particles which was based on several well-defined principles. Subsequently, many authors have carried out calculations using this theory, but which include extra subsidiary approximations. In this paper the original theory is reexamined and illustrative calculations performed in which subsidiary approximations are eliminated and thus enable a quantitative assessment of the accuracy of these approximations to be made. [ABSTRACT FROM AUTHOR]

This paper presents a description of the abstractions required for the expression and solution of the linear single-particle Schrödinger equation in a finite element basis. This paper consists of two disparate themes: First, to layout and establish the foundations of finite element analysis as an approximate numerical solution to extendable quantum mechanical systems; and second, to promote a high-performance open-source computational model for the approximate numerical solution to quantum mechanical systems. The structural foundation of the one-and two-dimensional time-independent Schrödinger equation describing an infinite potential well is explored and a brief overview of the hierarchal design of the computational library written in C++ is given. [ABSTRACT FROM AUTHOR]

In this paper a modification of the Smooth Particle Hydrodynamics (SPH) method is considered. This modification allows increasing the accuracy of calculation of shocks and contact discontinuities in hydrodynamic flows. This paper also presents a research which shows the influence of different kernel forms used in the SPH simulations, and also the influence of particle parameter difference in distinct simulation domains. An example of a test one-dimensional Riemann problem is used to compare the computations by a «standard» SPH-method, by the A.N.Parshikov’s method and also by a modified method presented in this paper. The comparison of the computation results with the exact solution in discrete analogs of the Chebyshev and L2 norms displays advantages of the offered modification. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In the so called ‘causal’ interpretation of quantum mechanics, an electron is considered as a particle and such particle is influenced not only by a classical but also by a so called quantum potential. This idea was developed by Professor Bohm in an important paper. In this paper we use some of the basics of this interpretation in a financial option pricing environment. The causal interpretation allows for trajectories. Path breaking work by Professors Bohm and Hiley and Khrennikov and Choustova have made that the causal interpretation is a step closer to potential applications in social science. In this paper we consider the wave function as a wave of information. We consider the gradient of the phase of this wave function and show how the option price could be influenced by this gradient. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The update of the particle momentum in an electromagnetic simulation typically employs the Boris scheme, which has the advantage that the magnetic field strictly performs no work on the particle. In an extreme field, however, it is found that onerously small time steps are required to maintain accuracy. One reason for this is that the operator splitting scheme fails. In particular, even if the electric field impulse and magnetic field rotation are computed exactly, a large error remains. The problem can be analyzed for the case of constant, but arbitrarily polarized and independent electric and magnetic fields. The error can be expressed in terms of exponentials of nested commutators of the generators of boosts and rotations. To second order in the field, the Boris scheme causes the error to vanish, but to third order in the field, there is an error that has to be controlled by decreasing the time step. This paper introduces a scheme that avoids this problem entirely, while respecting the property that magnetic fields cannot change the particle energy. [ABSTRACT FROM AUTHOR]

The paper investigates the possibility of obtaining analytical solutions for the Quark Gluon Plasma model using the Adomian decomposition method. [ABSTRACT FROM AUTHOR]

This paper describes industrial charged particle beamline technologies and design approaches. Beamlines accommodate myriad constraints in the radioisotope production, electron beam processing, and ion implantation market segments, and some very strange yet interesting solutions result. In this paper, a detailed look at a particular injection beamline solution gives some sense of the complexity of research and development required, and the sophistication of the beamline solutions that are utilized. A brief review of beamline applications in each industrial segment follows. [ABSTRACT FROM AUTHOR]

Do not replace the word “abstract,” but do replace the rest of this text. Text should remain 10-pt. If you must insert a hard line break, please use Shift+Enter rather than just tapping your “Enter” key. You may want to print this page and refer to it as a style sample before you begin working on your paper. For an experimentalist in high energy physics, the most interesting experiments that one should pursue is often well known. The very rare CP violating decay of the kaon into a pion and two neutrinos (both the charged and neutral modes) is such an experiment. We have recently proposed the charged kaon experiment to Fermilab as proposal P966. We present her a general overview of that proposal. The goal is to obtain of order 1000 events in order to confront the expected theoretical calculations and to search for physics beyond the standard model. [ABSTRACT FROM AUTHOR]

Electrical transport properties viz. electrical resistivity, thermoelectric power and thermal conductivity of liquid Al-Cu alloys as a function of Cu concentration have been studied in the present paper. Ashcroft empty core model potential has been used to incorporate the ion-electron interaction. To incorporate the exchange and correlation effects, five different forms of local field correction functions viz. Hartree, Taylor, Ichimaru et al., Farid et al. and Sarkar et al. have been used. The transport properties of binary system have been studied using Faber-Ziman formulation combined with Ashcroft-Langreth (AL) partial structure factor. The computed values of electrical resistivity are compared with experimental data and for low Cu concentration, good agreement has been observed. Further, thermoelectric power and thermal conductivity have also been predicted. [ABSTRACT FROM AUTHOR]

A three-dimensional MHD solver is described in the paper. The solver simulates reacting flows with nonequilibrium between translational-rotational, vibrational and electron translational modes. The conservation equations are discretized with implicit time marching and the second-order modified Steger-Warming scheme, and the resulted linear system is solved iteratively with Newton-Krylov-Schwarz method that is implemented by PETSc package. The results of convergence tests are plotted, which show good scalability and convergence around twice faster when compared with the DPLR method. Then five test runs are conducted simulating the experiments done at the NASA Ames MHD channel, and the calculated pressures, temperatures, electrical conductivity, back EMF, load factors and flow accelerations are shown to agree with the experimental data. Our computation shows that the electrical conductivity distribution is not uniform in the powered section of the MHD channel, and that it is important to include Joule heating in order to calculate the correct conductivity and the MHD acceleration. [ABSTRACT FROM AUTHOR]

In this paper the method of beam depolarization compensation during spin resonance crossing is developed. This method is based on the restoration of the spin adiabatic invariant after the spin resonance crossing. The case when the restoration of spin adiabatic invariant occurs due to multiple crossing of the resonance effective area is considered. At the same time it is necessary to provide the certain difference of spin phases between the moments of crossing of the resonance effective area. The conditions of beam polarization preservation when the resonance effective area is repeatedly crossed are obtained. Numerical examples are presented. [ABSTRACT FROM AUTHOR]

This paper examined the fusion of 28Si with 90,96Zr-target by opting the energy dependent Woods-Saxon potential (EDWSP) model and code CCFULL. The CCFULL analysis suggested that for 28Si + 90Zr system, the vibrational excitations of 90Zr-isotope have been found to be very important while for 28Si + 96Zr system, in addition to multiphoton vibrational states of target, the considerations of nucleon transfer are essentially needed for the adequate addressal of the observed fusion data. In contrast, predictions based on EDWSP model appropriately recovered the fusion data of 28Si + 90,96Zr systems at sub-barrier realm. The EDWSP based results do not include various channel coupling effects explicitly but being the energy dependent nature of Woods-Saxon potential (WSP), the calculational results intrinsically incorporate the nuclear effects of the fusing systems. This unambiguously clarified that the energy dependent nature of the EDWSP generates analogous barrier modulations as emerged from the CCFULL analysis. [ABSTRACT FROM AUTHOR]

The fundamental symmetries, charge conjugation (C), parity (P) and time reversal (T), play a significant role in the Standard Model (SM) of elementary particle physics. Of these, T symmetry and the combined CP symmetry are the least well understood, and they hold valuable clues for unraveling the secrets of nature. All subatomic particles are postulated to possess an intrinsic property known as a permanent electric dipole moment (EDM). The EDM of an atom is a combination of those of each constituent particle and also CP-violating interactions between the particles. Being many-particle systems, atoms and molecules are ideal candidates for probing a rich variety of both T- and CP-violating interactions. Paramagnetic atoms, which have a single valence electron in their outer shell, are sensitive to subtle signals associated with CP violations in the leptonic sector, i.e., the EDM of the electron. At present, we are developing a high-intensity laser-cooled Fr factory at RIKEN accelerator facility in an attempt to evaluate the EDM of Fr to an accuracy of 10-30 ecm. Laser cooling is important for achieving highly accurate EDM measurements, since it allows long interaction times using an optical lattice. The current status of the laser-cooled Fr EDM experiments is presented in this paper. [ABSTRACT FROM AUTHOR]

The paper is devoted to four-body Faddeev-type AGS equations, written down for the K ¯ NNN system, which is a system consisting of an antikaon and three nucleons. The aim is to find possible quasi-bound state in the system and calculate its properties. [ABSTRACT FROM AUTHOR]

Fermilab E906/SeaQuest is an experiment aimed at studying the anti-quark distributions of nucleons and nuclei. The experiment uses a 120 GeV/c proton beam extracted from the Main Injector at Fermilab to collide with various solid and cryogenic targets to study a variety of physics topics ranging from light anti-quark flavor asymmetry in the nucleon sea to dark photons. The experiment takes advantage of the Drell-Yan process in order to probe specifically the high-x anti-quark distributions of the target nucleus. The acceptance of the spectrometer is tuned to explore the unprecedentedly high Bjorken-x region, thereby extending our knowledge of the anti-quark sea structure of nucleons and nuclei. Some of the physics goals from the Drell-Yan program at SeaQuest and the current status of some analyses are reported in this paper. [ABSTRACT FROM AUTHOR]

Motivated by the recent abundant experimental data obtained from the continuous and heavy duty accelerators along with the precise and modern particle detectors, we have intensively analyzed the elementary kaon photoproduction processes from their production thresholds up to W ≈ 3 GeV in the last two decades. All possible isospin channels are considered in the analysis because recently experimental data have been available in all channels. This includes γp → K+Λ, K+Σ0, K0Σ+ processes off the proton and γn → K0Λ, K+Σ−, K0Σ0 processes off the neuron. In this proceedings paper we briefly report on the latest progress of our analysis. There are two approaches that have been used for this purpose, i.e., the isobar model which is based on the Effective Lagrangian Theory and the partial wave analysis, in which the corresponding multipoles are parameterized by means of the Breit-Wigner form. [ABSTRACT FROM AUTHOR]

An one-dimensional hybrid model of RF discharge in low-temperature argon plasma is presented in our paper. The hybrid model consists of two parts—particle model which simulates fast electrons while fluid model simulates slow electrons and positive argon ions. In the particle model the positions and velocities of fast electrons are calculated by means of deterministic Verlet algorithm while the collision processes are treated by the stochastic way. For the solution of fluid equations, for slow electrons and positive argon ions, the Scharfetter-Gummel exponential algorithm was used. Typical results of our calculations presented in this paper are total RF current and RF voltage waveforms on the planar substrate immersed into argon plasma. The next results which can be found here are the ion, electron and displacement current waveforms on the substrate. Especially, the knowledge of waveform of the ion current is very important for experimental physicists during the deposition of thin films. [ABSTRACT FROM AUTHOR]

In this paper results are presented for radiative KL decays from the KTeV experiment. Also presented is a determination of the ππ scattering length from the NA48 collaboration using the decay K± → π±π0π0. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In spite of the fact that statistical predictions of quantum theory (QT) can only be tested if large amount of data is available a claim has been made that QT provides the most complete description of an individual physical system. Einstein’s opposition to this claim and the paradox he presented in the article written together with Podolsky and Rosen in 1935 inspired generations of physicists in their quest for better understanding of QT. Seventy years after EPR article it is clear that without deep understanding of the character and limitations of QT one may not hope to find a meaningful unified theory of all physical interactions, manipulate qubits or construct a quantum computer.. In this paper we present shortly the EPR paper, the discussion, which followed it and Bell inequalities (BI). To avoid various paradoxes we advocate purely statistical contextual interpretation (PSC) of QT. According to PSC a state vector is not an attribute of a single electron, photon, trapped ion or quantum dot. A value of an observable assigned to a physical system has only a meaning in a context of a particular physical experiment PSC does not provide any mental space-time picture of sub phenomena. The EPR paradox is avoided because the reduction of the state vector in the measurement process is a passage from a description of the whole ensemble of the experimental results to a particular sub-ensemble of these results. We show that the violation of BI is neither a proof of the completeness of QT nor of its non-locality. Therefore we rephrase the EPR question and ask whether QT is “predictably “complete or in other words does it provide the complete description of experimental data. To test the “predictable completeness” it is not necessary to perform additional experiments it is sufficient to analyze more in detail the existing experimental data by using various non-parametric purity tests and other specific statistical tools invented to study the fine structure the time-series. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The antiproton celebrates its 50th birthday this year. Although its existence had been suspected since the discovery of the positron in 1932, there was still doubt in some quarters that such a companion particle to the proton could exist. I will try to trace the scientific history of the antiproton from that time to the publication of the definitive paper by Chamberlain, Segrè, Wiegand and Ypsilantis in November 1955, with a brief look at what happened next. The narrative will be supplemented with thoughts and opinions of some of the main actors, both at the time and in retrospect. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We investigate the energy dependence of the charge states of heavy ions during a number of gradual solar energetic particle events related to coronal mass ejections. The data of two instruments with complementary energy ranges, the Solar Energetic Particle Ionic Charge Analyzer SEPICA on ACE and the time-of-flight mass and charge spectrometer STOF on SOHO are used to cover the energy range from ∼ 0.02 to 0.7 MeV/amu for O and Fe. Measurements with SAMPEX and SEPICA/ACE contain evidence that some gradual CME related SEP events show energy dependent charge distributions. In the present paper we are closing the gap in the lower energy interval (STOF data) thus making future comparison to solar wind values — representative for coronal conditions — more reliable. We find that energy dependent charge states of Fe are almost ubiquitous in gradual SEP events. Very large differences from event to event are observed however. In cases of local acceleration at the CME driven shock the variation in the energy interval up to 0.5 MeV/amu is ∼ 1-2 charge units. In alternative cases the mean ionic charge variation for Fe reaches ∼4 charge units over the same energy interval. The respective charge spectra could be interpreted as the result of ionization near the sun, in the dense coronal plasma, with or without reaching charge state equilibrium. [ABSTRACT FROM AUTHOR]

In this paper (which is a continuation of our previous work [9]) we compute the greybody factors at low energies for asymptotically non-flat Schwarzschild-de Sitter black holes in (4 + n)-dimensions. The case of spin 1/2 particles is investigated. [ABSTRACT FROM AUTHOR]

Laudatio in honor of Dr. Miguel Ángel Pérez Angón, co-recipient of the 2008 Medal of the Division of Particles and Fields of the Mexican Physical Society [ABSTRACT FROM AUTHOR]

The nucleons are the basic elements of the light baryons. In this paper, we choose neutron (N) with a combination of one up(u) and two down(d) quarks. The ground state of N is determined with quantum number JP = 1/2+. Also, the first radial and orbital excited states are calculated. The results are compared with experimental masses as well as other theoretical predictions. [ABSTRACT FROM AUTHOR]

Lifetime measurements of b-flavoured hadrons can be used to test QCD predictions and to probe for CP violation in mixing and decay. This paper outlines a few of the experimental methods used to correct for the decay time bias introduced by the event selection and summarises recent measurements from the CMS, DØ and LHCb Experiments. [ABSTRACT FROM AUTHOR]

Magnetorheological elastomers (MREs) are composites that highly elastic polymer matrices are filled with magnetic particles. These materials exhibit unique characteristics that their modului can be controlled by an external magnetic field. This paper presents analysis, fabrication and characterization of novel patterned MREs. By taking into account the local magnetic field in MREs and particles' interaction magnetic energy, the magnetic field-dependent mechanical properties of MREs with lattice and BCC structures were theoretically analyzed and numerically simulated. Soft magnetic particles were assembled in polydimethylsioxane matrix to fabricate new MREs with uniformly lattice and BCC structures, which were observed by microscope. The field-dependent modulus of the new MREs was characterized by a parallel-plate rheometer. The experimental results agreed well with numerical simulations. [ABSTRACT FROM AUTHOR]

Milling is an important operation in many industries, such as mining and pharmaceutical. Although the comminution process during milling has been extensively studied, the material fragmentation mechanisms in a mill are still not well understood partly because of the lack of an understanding on the local stressing and dynamic information under operational conditions in mills. This paper presents a DEM simulation of particle dynamics and impact events in a centrifugal impact pin mill. The main focus is the statistical characteristics of the dominant stressing modes during the milling process. The frequency, velocity and force of the different impact events between particles and mill components, or between particles, are analysed. [ABSTRACT FROM AUTHOR]

The simulation of PIXE (Particle Induced X-ray Emission) is discussed in the context of general-purpose Monte Carlo systems for particle transport. Dedicated PIXE codes are mainly concerned with the application of the technique to elemental analysis, but they lack the capability of dealing with complex experimental configurations. General-purpose Monte Carlo codes provide powerful tools to model the experimental environment in great detail, but so far they have provided limited functionality for PIXE simulation. This paper reviews recent developments that have endowed the Geant4 simulation toolkit with advanced capabilities for PIXE simulation, and related efforts for quantitative validation of cross sections and other physical parameters relevant to PIXE simulation. [ABSTRACT FROM AUTHOR]

This paper is a brief historical review of the quest to find neutrinos of extraterrestrial origin. In the context of the Victor Hess centenary, it is interesting to consider how the development of detectors for neutrinos from space relates to developments in cosmic-ray and particle physics over the same time span. [ABSTRACT FROM AUTHOR]

An observed plateau abundance of 7Li in metal-poor halo stars indicates its primordial origin. The 7Li abundances are about a factor of three smaller than that predicted in standard big bang nucleosynthesis (BBN) model. In addition, some of the stars possibly contain 6Li in abundances larger than standard BBN prediction. Particle models sometimes include heavy longlived colored particles which are confined in exotic strongly interacting massive particles (SIMPs). We have found reactions which destroy 7Be and 7Li during BBN in the scenario of BBN affected by a long-lived sub-strongly interactingmassive particle (sub-SIMP, X). The reactions are non radiative X captures of 7Be and 7Li which can operate if the X particle interacts with nuclei strongly enough to drive 7Be destruction but not strongly enough to form a bound state with 4He of relative angular momentum L = 1. The processes can be a cause of the 7Li problem. In this paper we suggest new possible reactions for 6Li production. Especially, a 6Li production through the deuteron capture of 4He bound to X can operate in the parameter region solving the 7Li problem. [ABSTRACT FROM AUTHOR]

The result of the general theory of the velocity dynamics of time-dependent chaotic billiards, according to the theory of Gelfriech and Turaev (2008), is that the average velocity of an ensemble of particles in a generic time-dependent billiard grows linearly with time [1]. This paper deals with the class of conformally driven time-dependent chaotic billiards which do not satisfy the assumptions of the theory about the properties of a generic system, which is analyzed in details. It is shown why the average velocity of an ensemble of conformally breathing billiards grows as ν∝t1/5. [ABSTRACT FROM AUTHOR]

In order to be able to predict extremely hazardous energetic particles from the Sun, it is important to understand the factors that control the onset behavior and peak flux of solar energetic particle (SEP) events. The shock properties should be naturally important for so-called gradual SEP events, which are believed to result from acceleration at shocks driven by coronal mass ejections (CMEs). Magnetic connection of the CME source region and adjacent regions to the observer may also play a role in the early development of SEP events. Now with STEREO, SEP events can be observed at three widely separated locations. We study such SEP events that occurred in August 2010. Although their proton flux was modest, they also lack the anomaly in abundance that is characteristic of impulsive SEP events. Therefore they are likely to be shock-accelerated gradual SEP events. In this paper we take up one of those events and try to explain their different temporal profiles of near-relativistic electrons at Earth and two STEREO spacecraft in terms of the proposition that first arriving particles are released when the acceleration region intersects well-connected field lines. We discuss how wave-like motions seen in EUV images from SDO and STEREO could indicate the shock waves responsible for SEP events. [ABSTRACT FROM AUTHOR]

The analysis of the sample of charged current quasi elastic events collected by the Mini-BooNE collaboration shows that the extension of the approaches successfully employed to describe electron-nucleus scattering to the case of neutrino interactions involves non trivial difficulties. In this paper it is argued that, due to flux average, the double differential neutrino-nucleus cross section does not allow for a clearcut determination of the dominant reaction mechanism. A systematic study of the large body of electron scattering data may help to identify the processes, other than single nucleon knockout, contributing to the observed neutrino cross section. [ABSTRACT FROM AUTHOR]

Ultra-high-energy cosmic rays (UHECRs) refer to cosmic rays with energy above 1018 eV. UHECR experiments utilize simulations of extensive air shower to estimate the properties of UHECRs. The Telescope Array (TA) experiment employs the Monte Carlo codes of CORSIKA and COSMOS to obtain EAS simulations. In this paper, we compare the results of the simulations obtained from CORSIKA and COSMOS and report differences between them in terms of the longitudinal distribution, Xmax-value, calorimetric energy, and energy spectrum at ground. [ABSTRACT FROM AUTHOR]

This is my contribution to the commemoration of my great friend Giuseppe ('Beppe') Nardulli who left us in June 2008. [ABSTRACT FROM AUTHOR]

High energy density science probes some of the most basic scientific questions that cut across traditional disciplines. The advent of table top, terawatt, femtosecond lasers promises to revolutionize this area by the use of precise experimental techniques on the one hand and testing of models and computer simulations on the other. In this paper, we present some of our results on hot electron generation, giant magnetic fields and ultrafast plasma dynamics using such experiments and theoretical modeling. [ABSTRACT FROM AUTHOR]

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference has been shown to produce up to three orders of magnitude speed-up in calculations from first principles of stages in the 100 MeV-10 GeV energy range. Maximum obtainable speedups calculated using linear theory predict that higher speedups are attainable, in the range of 4-6 orders of magnitude for stages in the energy range of 10 GeV-1 TeV respectively. Practical limitations have been reported and discussed which have prevented reaching these speedups so far, including a violent high frequency numerical instability. The limitations are briefly reviewed and discussed in this paper, as well as their mitigation. It is also reported that the high frequency numerical instability can be controlled effectively using novel numerical techniques that have been implemented in the Particle-In-Cell code Warp, and that 5 and 6 orders of magnitude speedups were demonstrated on 100 GeV and 1 TeV stages respectively, verifying the scaling of plasma accelerators to very high energies, and providing highly efficient tools for the detailed designs of experiments on new lasers such as BELLA. [ABSTRACT FROM AUTHOR]

A strong demand for high gradient structures arises from the limited real estate available for linear accelerators. RadiaBeam Technologies is developing a Doubled Energy Compact Accelerator (DECA) structure: an S-band standing wave electron linac designed to operate at accelerating gradients of up to 50 MV/m. In this paper, we present the radio-frequency design of the DECA S-band accelerating structure, operating at 2.856 GHz in the π-mode. The structure design is heavily influenced by NLC collaboration experience with ultra high gradient X-band structures; S-band, however, is chosen to take advantage of commonly available high power S-band klystrons. [ABSTRACT FROM AUTHOR]

In this paper one presents further details concerning the derivation of exact bound state energies characterizing a single electron moving on two-dimensional heterostructures under Rashba-and Dresselhaus spin-orbit interactions in the presence of a transversal magnetic field. One resorts to algebraic methods as well as to symmetry relationships concerning the mutual conversion of interactions mentioned above. [ABSTRACT FROM AUTHOR]

The objectives of this project is install at the 2.75 GeV SOLEIL synchrotron radiation source a calibration and metrology test facility for the R&D of optical components and detectors. We have build, on a bending magnet, two branches to cover an energy range from few eV to 28 keV and give access to white beam. This installation will first address the needs of the SOLEIL experimental groups (Optics and Detectors) and will be used by a large community. This beamline will also be valuable as a general-purpose beamline to prepare, test and set up a wide range of experiments in the field of Astrophysics, laser plasma etc ... A complementary important aspect of this installation is the realization of primary standard: the metrology beamline of SOLEIL could become the national primary standard source in collaboration with the Laboratoire National d’Essais (LNE) and help in the design and characterization of several diagnostics for the Megajoule Laser in Bordeaux in collaboration with the CEA DIF. The beamline has been designed to provide great flexibility. In this paper, we describe the beamline design, the end station instrumentation and give also some preliminary results. [ABSTRACT FROM AUTHOR]

To simplify the complicated mechanism of the traditional double crystal monochromator for synchrotron radiation, a kind of channel cut monochromator with curved reflecting surfaces to fix the exit beam position was successfully developed at NSRL. The performance of this monochromator, which includes the relative efficiency, diffraction bandwidth and deviation of the beam spot, was calculated and measured. The analysis of these results are presented in this paper. [ABSTRACT FROM AUTHOR]

This paper describes the design and fabrication of safety shutter for the Indus-2 synchrotron source on bending magnet front-ends. The purpose of the safety shutter is to absorb Bremsstrahlung radiation generated due to scattering of electron beam from residual gas ions and components of the storage ring. The safety shutter consists of a radiation absorber actuated inside a rectangular ultra high vacuum chamber by pneumatic actuator. A water-cooled copper block is mounted before the absorber block to protect it from the incident heat load due to synchrotron radiation. The top flanges of the chamber are made with rectangular knife edge sealing which is found to be better than wire seal at higher temperature. The physics aspect of safety shutter is designed using simulation code Electron Gamma Shower EGS-4 code. [ABSTRACT FROM AUTHOR]

At the high energy synchrotron radiation beamline BW5 at DORIS III at DESY a new monochromator providing broad energy bandwidth and high reflectivity is in use. On a small 10×10×5 mm3 silicon crystal scattering at the (311) reflection a thermal gradient is applied, which tunes the scattered energy bandwidth. The (311) reflection strongly suppresses the higher harmonics allowing the use of an image plate detector for crystallography. The monochromator can be used at photon energies above 60 keV. [ABSTRACT FROM AUTHOR]

To enhance the performance of Hefei Light Source, which was designed and constructed two decades ago, an upgrade project would be carried out in the near future. The detail upgrade scheme was described in this paper. Firstly, the magnet lattice of storage ring should be reconstructed with 4 DBA cells, whose advantages are lower beam emittance and more straight section available for insertion devices. Secondly, the beam diagnostics, main power supply, transverse and longitudinal multi-bunch feedback, beam control and manipulation system would be upgrade to improve the beam orbit stability. Finally, the injection system of storage ring and injector, which is composed of electron linac and beam transfer line, would be updated in order to assure smooth beam accumulation process under new low emittance lattice. With above improvement, it is hopeful to increase the brilliance of Hefei Light Source by two orders approximately. After three-year upgrade project, the performance of HLS would meet the demands of advanced SR users. [ABSTRACT FROM AUTHOR]

In this paper we study Bogomolnyi-Prasad-Sommerfeld (BPS) domain walls of five dimensional gauged N = 2 supergravity coupled to a hypermultiplet whose scalars span a four dimensional toric self dual Einstein space, namely a four dimensional self dual Einstein space with torus symmetry. The walls preserve half of supersymmetry and are described by the gradient flow equations called BPS equations. An interesting feature is that the dynamics of such equations are determined by a real superpotential and the shape of two dimensional hyperbolic spaces defined on the upper half plane. [ABSTRACT FROM AUTHOR]

Ion beam emission/neutralization is one of the most fundamental problems in spacecraft plasma interactions and electric propulsion. Although ion beam neutralization is readily achieved in experiments, the understanding of the underlying physical process remains at a rather primitive level. No theoretical or simulation models have convincingly explained the detailed neutralization mechanism, and no conclusions have been reached. This paper presents a fully kinetic simulation of ion beam neutralization and plasma beam propagation and discusses the physics of electron-ion coupling and the resulting propagation of a neutralized mesothermal plasma. [ABSTRACT FROM AUTHOR]