Search

The γ p → K + Σ 0 differential cross section at extremely forward angles was measured at the BGOOD experiment. A three-quarter drop in strength over a narrow range in energy and a strong dependence on the polar angle of the K + in the centre-of-mass of the reaction is observed at a centre-of-mass energy of 1900 MeV. Residing close to multiple open and hidden strangeness thresholds, the structure appears consistent with meson-baryon threshold effects which may contribute to the reaction mechanism.

For a class of polynomial quantum Hamiltonians used in models of combination scattering in quantum optics, we obtain the asymptotic behavior of the spectrum for large occupation numbers in the secondary quantization representation. Hamiltonians of this class can be diagonalized using a special system of polynomials determined by recurrence relations with coefficients depending on a parameter (occupation number). For this system of polynomials, we determine the asymptotic behavior a discrete measure with respect to which they are orthogonal. The obtained limit measures are interpreted as equilibrium measures in extremum problems for a logarithmic potential in an external field and with constraints on the measure. We illustrate the general case with an exactly solvable example where the Hamiltonian can be diagonalized by the canonical Bogoliubov transformation and the special orthogonal polynomials degenerate into the Krawtchouk classical discrete polynomials.

Photonuclear methods used earlier in experiments at electron accelerators have been adapted for femtosecond pulsed lasers. In particular, the problem of measuring wide electron spectra under conditions of a high counting rate and, hence, a high probability of pulse pileup has been solved. To provide long-term stability of electron beams from plasma, a magnetic spectrometer combined with a magnetic-induction sensor has been developed. This spectrometer is capable of measuring the electron-beam characteristics in each ultrashort laser pulse. The results of the experiments carried out with the femtosecond laser system at the International Laser Center of the Moscow State University are presented.

An algorithm is proposed that provides reliable discrimination between neutrons and γ rays in mixed fields and reduces the influence of γ-ray pileups at a slight complication of the hardware and the algorithms. The algorithm uses a stepwise Gatti filter for two detection periods (a short period of several hundreds of nanoseconds and a long period of a few microseconds) for the same event. Using mathematical simulation of 12000 neutron and γ-ray events, it has been demonstrated that at particle energies of ~128 keV in the electron equivalent (ee), the algorithm suppresses γ-ray pileups on a level of 104 with a neutron loss of only approximately 1%. Due to the proposed algorithm, the counting ability is of the order of 105 events/s.

New data on the fragmentation of carbon nuclei by photons with energies from 800 to 1500 MeV, obtained in the collaboration GRAAL, are presented. These data include the yields of heavier fragments than nucleons. Comparison of new results with literature data, obtained with real and virtual photons in reactions with electrons and relativistic ions (Coulomb dissociation) is done using a general approach in frame of the Weizsacker–Williams model. Possible reasons for the observed differences between them are discussed.

A brief overview of the methods for separating the contributions of isovector electric quadrupole (E2) and dominant dipole (E1) giant resonances in atomic nuclei, which are excited in direct and inverse reactions with photons (real and virtual), is given. The basic parameters of isovector giant resonance E2, which were declared to date by applying some of these methods to the results with 208Pb, are also presented.

The development of a personalized nutritional approach to diet therapy for patients with obesity and hyperuricemia, aimed at increasing the treatment effectiveness of these patients, is an urgent task.

The BGO-OD experiment at the ELSA accelerator facility uses an energy tagged bremstrahlung photon beam to investigate the excitation structure of the nucleon. The setup consists of a highly segmented BGO calorimeter surrounding the target, with a particle tracking magnetic spectrometer at forward angles. BGO-OD is ideal for investigating low momentum transfer processes due to the acceptance and high momentum resolution at forward angles. In particular, this enables the investigation of strangeness photoproduction where t-channel exchange mechanisms play an important role. This also allows access to a kinematic region where extended, molecular structure may manifest in reaction mechanisms. The extensive strangeness photoproduction programme includes the photoproduction of neutral and charged kaons using both hydrogen and deuterium targets.

The cross sections of carbon nucleus photodisintegration into protons and neutrons with high multiplicity for photon energies from 700 to 1500 MeV were measured. The experiment was performed at the tagged photon beam of the GRAAL setup using the wide-aperture detector LAGRANγE. It was shown that multifragmentation up to complete disintegration into separate nucleons is initiated by elementary reactions of meson photoproduction with a subsequent intranuclear cascade.

Obesity is a violation of carbohydrate and fat metabolism, which further affects the micronutrient status. The volume of distribution of lipophilic substances (including fat-soluble vitamins) also increases in proportion to fat mass. To date, there is much evidence that obese people have lower serum levels of vitamins A and D. Moreover, obesity leads to a decrease in vitamin D endogenous synthesis. The developed vitamins A and D deficiency aggravates carbohydrate and fat metabolism. A vicious circle forms. Obesity is also associated with lower concentrations of water-soluble vitamins. People with an increased BMI often face thiamine, folate, and ascorbic acid deficiency. Firstly, the excretion of these vitamins increases because of their evaluated expenditure. Secondly, the diet of obese patients often lacks vegetables and fruits, which results in reduced intake of folic and ascorbic acids. Obese people are at greater risk of developing zinc, manganese, magnesium, chromium, and vanadium deficiency. This is due to the increased need for these elements in obesity because they are involved in carbohydrate and fat metabolism. Moreover, the nutritional intake of these micro- and trace elements is also often reduced in people who consume not enough plant foods. The existing recommended dietary allowances for micronutrients are standard, but it seems necessary to develop specific norms for patients with obesity on different stages. The assessment of micronutrient supply in obese patients is challenging. It's not fully understood how vitamins, macro- and trace elements serum levels reflect their status in the organism considering the significantly changed nutrient kinetics of obese patients compared to the average population.

Since the discovery of the Λ(1405), it remains poorly described by conventional constituent quark models, and it is a candidate for having an “exotic” meson-baryon or “penta-quark” structure, similar to states recently reported in the hidden charm sector.The Λ(1405) can be produced in the reactionγpK+Λ(1405). The pure I=0 decay mode into Σ0π0is prohibited for the mass-overlapping Σ(1385). Combining a large aperture forward magnetic spectrometer and a central BGO crystal calorimeter, the BGO-OD experiment is ideally suited to measure this decay with theK+in the forward direction. Preliminary results are presented.*Supported by DFG (PN 388979758, 405882627)

In general, industries produce waste, which causes environmental pollution and is a danger to living things. Chromium heavy metal waste is one type of waste that has high toxicity that can lead to chronic poisoning, acute, and can cause cancer. Biological treatment is a choice to reduce the concentration of heavy metals in environmental media. This study uses a biosorption column that utilizes Saccharomyces cerevisiae bacteria using bacterial biomass made in a state of silence in a continuous column, then flowing Cr (VI) metal solution downflow with a constant flow rate. Laboratory analysis results show that the removal efficiency of Cr (VI) for the initial pH 3 solution is 44.74% - 77.84%, the pH 5 treatment is 7.52% - 30.54% and the pH 7 treatment is 5.80% - 11.40%. The highest removal efficiency occurred at pH 3 of 77.84%. The remaining metal concentrations in the barrel can reduce to 11.08 mg/L.

The nonlocal implementation of the dispersive optical model (DOM) provides all the ingredients for distorted-wave impulse-approximation (DWIA) calculations of the $(e,e'p)$ reaction. It provides both the overlap function, including its normalization, and the outgoing proton distorted wave. This framework is applied to describe the knockout of a proton from the $0\textrm{d}\frac{3}{2}$ and $1\textrm{s}\frac{1}{2}$ orbitals in ${}^{40}$Ca with fixed normalizations of 0.71 and 0.60, respectively. Data were obtained in parallel kinematics for three outgoing proton energies: 70, 100, and 135 MeV. Agreement with the data is as good as, or better than, previous descriptions employing local optical potentials and overlap functions from Woods-Saxon potentials - both with standard nonlocality corrections - whose normalization (spectroscopic factor) and radius were fitted to the data. The present analysis suggests that slightly larger spectroscopic factors are obtained when nonlocal optical potentials are employed than those generated with local potentials. The results further suggest that the chosen kinematical window around 100 MeV proton energy provides the best and cleanest method to employ the DWIA for the analysis of this reaction. The conclusion that substantial ground-state correlations cannot be ignored when describing a closed-shell atomic nucleus is therefore confirmed in detail. To reach these conclusions, it is essential to have a complete description of the nucleon single-particle propagator that accounts for all elastic nucleon-scattering observables in a wide energy domain up to 200 MeV. The current nonlocal implementation of the DOM fulfills this requirement., 15 pages, 11 figures