On the design of experiments to study extreme field limits

We propose experiments on the collision of high intensity electromagnetic pulses with electron bunches and on the collision of multiple electromagnetic pulses for studying extreme field limits in the nonlinear interaction of electromagnetic waves. The effects of nonlinear QED will be revealed in these laser plasma experiments.Comment: 7 pages, 3 figures, 1 table; 15th Advanced Accelerator Concepts Workshop (AAC 2012), Austin, Texas, 10-15 June, 201

THE RUSSIAN DATA OF INTERNATIONAL ENDORSE REGISTER (EPIDEMIOLOGIC INTERNATIONAL DAY FOR THE EVALUATION OF PATIENTS AT RISK OF VENOUS THROMBOSIS IN ACUTE HOSPITAL CARE SETTING)

Aim. To estimate a risk factor frequency of venous thromboembolism (VTE) in patients urgently hospitalized in hospitals, and also to estimate of patients part having effective prevention of VTE.Material and methods. ENDORSE (Epidemiologic International Day for the Evaluation of Patients at Risk of Venous Thrombosis in Acute Hospital Care Setting) is the international register. Patients of 40 years and older hospitalised in therapeutic departments as well as patients of 18 years and older hospitalised in surgical departments (358 hospitals in 32 countries) were included in the register. The case history analysis of all patients was performed for estimation of risk VTE and evaluation of preventive therapy quality according to American College of Chest Physicians (ACCP) Recommendation 2004.Results. Totally 68 183 patients (including 30 827 (45%) surgical patients and 37 356 (55%) therapeutic patients) were enrolled in Global ENDORSE Register. Russian centers enrolled 4 788 patients (including 2 829 (59%) surgical patients and 1 959 (41%) therapeutic patients). Totally 35 329 (51,8%) patients enrolled in Global ENDORSE Register (64,4% of surgical patients (19 842) and 41,5% of therapeutic patients (15 487)) had VTE risks. In Russia 2 188 enrolled patients (45,7%) had VTE risks (52% of surgical patients (1 470) and 36,7% of therapeutic patients (718). Totally 17 732 (50,2%) patients enrolled in Global Register ENDORSE and having VTE risks received VTE preventive therapy according to АССР Recommendations 2004. In Russia 521 (23,8%) patients enrolled in Global ENDORSE Register and having VTE risks received VTE preventive therapy according to АССР Recommendations 2004. It is more than 2 times less in comparison with world level (р<0.001).Conclusion. There are a lot of patients with VTE risks in hospitals. It is necessary to improve preventive therapy of VTE due to better hospital management and more active use of АССР Recommendations 2004

Structures and waves in a nonlinear heat-conducting medium

The paper is an overview of the main contributions of a Bulgarian team of researchers to the problem of finding the possible structures and waves in the open nonlinear heat conducting medium, described by a reaction-diffusion equation. Being posed and actively worked out by the Russian school of A. A. Samarskii and S.P. Kurdyumov since the seventies of the last century, this problem still contains open and challenging questions.Comment: 23 pages, 13 figures, the final publication will appear in Springer Proceedings in Mathematics and Statistics, Numerical Methods for PDEs: Theory, Algorithms and their Application

Observation of narrow baryon resonance decaying into pKs0pK^0_s in pA-interactions at 70GeV/c70 GeV/c with SVD-2 setup

SVD-2 experiment data have been analyzed to search for an exotic baryon state, the $\Theta^+$-baryon, in a $pK^0_s$ decay mode at $70 GeV/c$ on IHEP accelerator. The reaction $pA \to pK^0_s+X$ with a limited multiplicity was used in the analysis. The $pK^0_s$ invariant mass spectrum shows a resonant structure with $M=1526\pm3(stat.)\pm 3(syst.) MeV/c^2$ and $\Gamma < 24 MeV/c^2$. The statistical significance of this peak was estimated to be of $5.6 \sigma$. The mass and width of the resonance is compatible with the recently reported $\Theta^+$- baryon with positive strangeness which was predicted as an exotic pentaquark ($uudd\bar{s}$) baryon state. The total cross section for $\Theta^+$ production in pN-interactions for $X_F\ge 0$ was estimated to be $(30\div120) \mu b$ and no essential deviation from A-dependence for inelastic events $(\sim A^{0.7})$ was found.Comment: 8 pages, 7 figures, To be submitted to Yadernaya Fizika. v3-v5 - Some references added, minor typos correcte

Exotic dense-matter states pumped by a relativistic laser plasma in the radiation-dominated regime

In high-spectral resolution experiments with the petawatt Vulcan laser, strong x-ray radiation of KK hollow atoms (atoms without n = 1 electrons) from thin Al foils was observed at pulse intensities of 3 x 10(20) W/cm(2). The observations of spectra from these exotic states of matter are supported by detailed kinetics calculations, and are consistent with a picture in which an intense polychromatic x-ray field, formed from Thomson scattering and bremsstrahlung in the electrostatic fields at the target surface, drives the KK hollow atom production. We estimate that this x-ray field has an intensity of >5 x 10(18) W/cm(2) and is in the 3 keV range

Liquid low-level radioactive wastes treatment by using hydrophobized track-etched membranes

In this paper, we present the results of liquid low-level radioactive wastes (LLLRW) treatment by direct contact membrane distillation (DCMD) using polyethylene terephthalate (PET) track-etched membranes (TeMs). PET TeMs were modified by styrene and triethoxyvinylsilane (TEVS) using UV-induced grafting. Modification led to increase in the contact angle to 99° of PET TeMs (pore size from 150 to 300 nm). Hydrophobic PET TeMs were investigated by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), goniometric analysis, gas permeability test, liquid entry presser (LEP) analysis and scanning electron microscope (SEM). Prepared membranes were tested in treatment of LLLRW by DCMD. The influence of pore size on water flux and rejection degree was studied. Rejection degree was evaluated by conductometry and atomic emission methods. Decontamination factors (evaluated by gamma-ray spectroscopy) for 60Co, 137Cs, and 241Am were found to be 85, 1900 and 5 respectively. In most cases degree of rejection of Cs, Mo, Sr, Sb, Al, Ca, Fe, K, Mg and Na ions were more than 90% and close to 100%. The use of TeMs with a narrow pores size distribution and without tortuous channels allowed us to achieve better purification from radioactive wastes in comparison with hollow-fiber membranes. © 2019 Elsevier LtdMinistry of Education and Science of the Republic of Kazakhstan: AP05132110This study was funded by the Ministry of Education and Science of the Republic of Kazakhstan (grant No AP05132110 “Preparation of track-etched membranes with specified properties for membrane distillation and forward osmosis”)

X-ray spectroscopy of super-intense laser-produced plasmas for the study of nonlinear processes. Comparison with PIC simulations

We present X-ray spectroscopic diagnostics in femto-second laser-driven experiments revealing nonlinear phenomena caused by the strong coupling of the laser radiation with the created plasma. Among those nonlinear phenomena, we found the signatures of the Two Plasmon Decay (TPD) instability in a laser-driven CO2 cluster-based plasma by analyzing the Langmuir dips in the profile of the O VIII Lyϵ line, caused by the Langmuir waves created at the high laser intensity 3 1018Wcm-2. With similar laser intensities, we reveal also the nonlinear phenomenon of the Second Harmonic Generation (SHG) of the laser frequency by analyzing the nonlinear phenomenon of satellites of Lyman δ and ϵ lines of Ar XVII. In the case of relativistic laser-plasma interaction we discovered the Parametric Decay Instability (PDI)-induced ion acoustic turbulence produced simultaneously with Langmuir waves via irradiation of thin Si foils by laser intensities of 1021Wcm-2

On the production of flat electron bunches for laser wake field acceleration

We suggest a novel method for injection of electrons into the acceleration phase of particle accelerators, producing low emittance beams appropriate even for the demanding high energy Linear Collider specifications. In this paper we work out the injection into the acceleration phase of the wake field in a plasma behind a high intensity laser pulse, taking advantage of the laser polarization and focusing. With the aid of catastrophe theory we categorize the injection dynamics. The scheme uses the structurally stable regime of transverse wake wave breaking, when electron trajectory self-intersection leads to the formation of a flat electron bunch. As shown in three-dimensional particle-in-cell simulations of the interaction of a laser pulse in a line-focus with an underdense plasma, the electrons, injected via the transverse wake wave breaking and accelerated by the wake wave, perform betatron oscillations with different amplitudes and frequencies along the two transverse coordinates. The polarization and focusing geometry lead to a way to produce relativistic electron bunches with asymmetric emittance (flat beam). An approach for generating flat laser accelerated ion beams is briefly discussed.Comment: 29 pages, 5 figure