In this article, a method for measuring the magnetic fields of wigglers and undulators based on a wire with a pulsed current as a high-speed alternative to Hall measurements is considered. An experimental setup for measurements is described. Correcting algorithms of the initial data are applied in order to eliminate the influence of wire dispersion and electronics noise. The obtained results and further work are discussed.

A non-standard analysis of the dielectric loss spectrum of liquid water in the Debye relaxation region (108–1013 Hz) is carried out in terms of dynamic conductivity σ(ν), with the Debye dielectric loss dome represented as the spectral trapezoid of an overdamped Lorentzian oscillator. Debye relaxation, in this framework, reflects the low-frequency tail of a strongly overdamped molecular oscillatory process with a characteristic frequency around 0.3 THz. The effectiveness of the σ-approach for identifying the relationship between the dielectric response and the self-diffusion D and viscosity η coefficients of liquid water is shown. Analytical expressions that link the dielectric and transport parameters of liquid water over a wide temperature range, from the triple point to the critical point (273–647 K), are derived.

A superconducting undulator created at the Budker Institute of Nuclear Physics with a period of 15.6 mm and a field of 1.2 T is tested in own undulator cryostat based on indirect cooling with zero helium consumption. The main characteristics and design features of the magnetic and cryogenic systems of this insertion device are presented. Results from measuring the magnetic field are presented. Features of the operation of a cryogenic system in different modes are discussed.

Stretched wire with direct current magnetic measurements method is used for producing synchrotron radiation generation insertion devices. The method allows to measure and to minimize the first and the second magnetic field integrals. The paper focuses on the wire sag problem.

The results of testing and performance characteristics of an indirectly cryocooled superconducting solenoid to be used at the tehrahertz (THz) spectroscopy experimental station of the free-electron laser at the Institute of Nuclear Physics are presented. The superconducting solenoid with a winding diameter of 102 mm and a length of 0.5 m is designed for a magnetic field of 6.5 T. A warm diameter of 80 mm is available for THz spectroscopy experiments. A superconducting wire Cu/NbTi = 1.4 is used. The design implements passive protection methods due to sectioning and secondary connected circuits in case of a sudden quench. The required field uniformity of 0.5% is ensured by using an iron yoke and additional side windings. The cryogenics of the solenoid is based on two Sumitomo HI cryocoolers. The solenoid and iron yoke are cooled by the second stage of the cryocooler via copper plates. The manufacturing technology of the solenoid is described in detail. The solenoid is tested in a liquid-helium bath and in its own cryostat. Its characteristics meet the requirements of the experimental station. The obtained field of 7.3 T is greater than the designed one due to overcooling up to 3.6 K. The magnetic field is measured both in a bath cryostat and in the designed cryostat; the results corresponded to the design calculations. The solenoid cooling time is 13 days. The quench happened only twice, at 5.6 and 7.3 T.

The main devices for generating synchrotron radiation at the SKIF synchrotron light facility under construction will be superconducting wigglers and undulators created at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. This report presents the rationale for the choice of operating parameters, the main characteristics and design features of these devices, and their current development status.

The authors describe a way of tuning the magnetic field of a superconducting undulator with neutral poles developed at the Budker Institute of Nuclear Physics, along with a mathematical apparatus for calculating additional power currents for tuning a magnetic field. The field and orbit inside the undulator are tuned by primary undulator windings arranged into separate groups and powered by additional currents. The tuning circuit is tested, and theoretical and experimental data on the measured magnetic field and calculated phase errors are compared. Spectra of synchrotron irradiation before and after tuning are calculated with the SPECTRA software.

The superconducting undulator with a 15.6-mm period and a 1.2-T magnetic field, described in this article, has a 8-mm magnetic gap. The magnetic measuring system under such conditions requires the use of a special tube (ante-chamber) inside the undulator’s magnetic gap. The thermal insulation between the cold magnet and this measuring tube is not enough to have a stable temperature along full length of the tube. The range of temperatures in this tube is 55–300 K. Hall probe measurements in this case are a complicated problem. Ways of measuring and processing results are described.

The problem of choosing a model for the description of broad absorption–dispersion relaxation bands in spectra of the dielectric response of substances is discussed. An example of overcoming the difficulty of describing dielectric spectra of liquid water in which the Debye relaxator is replaced by the overdamped Lorentzian oscillator is presented.

Magnetic measurements using a stretched wire with a constant current are widely used in manufacturing insertion devices for generating synchrotron radiation. They allow the first and second magnetic field integrals to be measured and minimized along the trajectory of the beam inside the accelerator. The problem of wire sag is also considered.

Based on information extracted from the published literature, we analyze the current state of knowledge on the properties of liquid water. There is a discrepancy between the efforts made and the results achieved. There is still no common model and clear prospects. While searching for an optimal solution to the problem, we propose to use the gas–solid-state Frenkel approach, which takes the interconversion of molecules and ions into account. It is demonstrated that this model can be used to provide a uniform and consistent description of the most important parameters of liquid water such as dielectric constant, evaporation enthalpy, self-diffusion coefficient, viscosity, and thermal conductivity.

The inclusive differential cross sections for the production of $$\pi^{\pm}$$ and $$k^{-}$$ mesons, protons, and antiprotons with momenta between 6 and 50 GeV/c and nuclear fragments of mass number $$1\leq A\leq 10$$ in the momentum range between 20 and 220 GeV/c were measured in carbon–lead collisions at a beam kinetic energy of 19.6 GeV per nucleon ( $$\sqrt{S_{NN}}=6.3$$ GeV). A comparison with the respective cross sections for carbon–carbon interactions is performed, and the dependence on the target mass number ( $$A$$ ) is estimated. The present analysis shows that the observed particles originate predominantly from peripheral interactions.

Analytical solutions for amplitude and time measurements from digitized signals of the pseudo-Gaussian shape are considered. The least squares method (l.s.m.) is chosen as the algorithm to determine amplitude A and timestamp t0. For a profile with an uncorrelated sampling the l.s.m. is reduced to analytical formulas consistent with the experiment. This permits to estimate the desired number of points Ns on a profile. The obtained results for Ns are illustrated with qualitative estimates in accordance with the Nyquist–Shannon–Kotelnikov sampling theorem. The optimality of the electronic filters forming the waveform is analyzed in terms of the excess noise factor. An analytical solution is found for the autocorrelation function from stochastic noise sources. It permits to define non-diagonal weight matrix elements in the l.s.m. with formulation of requirements for neglecting sampling correlations.

Water's properties are exceptional at low temperatures. Dielectric constant demonstrates ferroelectric-like behavior. We treat an idea to interpret the fundamental feature of water, 240 K singularity, through the Maxwell speed distribution of freely moving water molecules. We use the ion-molecular model recently proposed by us, in which water molecules make the translation-oscillator movement with rapid potential/kinetic energy transformation. The model provides direct access to the velocity distribution through the kinetic energy of free thermal motion.

The inclusive differential cross sections for forward production of nuclear fragments at an angle of 0∘ in CC collisions at beam energy 20.5 GeV/nucleon (SNN=6.3GeV) are presented. Measurements have been performed at the U-70 Accelerator Complex (Protvino) using a combined spectrometer on base of the beamline. Fragments selection was carried out by measuring of ionization in scintillation counters taking into account the data from threshold Cherenkov counters and hadron calorimeter. Fragment mass was determined through Cherenkov light emission angle measured in the spectrometer of ring imaging Cherenkov radiation. Data are given for fragments with charge 1≤Z≤6, atomic number 1≤A≤10 and A/Z<3.4 with momenta from 20 to 210 GeV/c. The measurements are compared with Fritiof model, statistical models and theoretical parameterizations. The discovered differences between theory and experiment are discussed.

Superconducting multipole insertion devices (wigglers and undulators) used to generate synchrotron radiation significantly increase the photon flux, especially in the hard spectral region. Over the past 35 years, more than 25 superconducting wigglers for leading centers of synchrotron radiation have been created at the BINP. A cryogenic system based on cryocoolers has been developed, which makes is possible to operate superconducting insertion devices for several years without consuming liquid helium. In this paper, the characteristics of various superconducting insertion devices created at the BINP are presented. The design features and recent advances in the development of the magnetic and cryogenic system with liquid and indirect cooling are discussed.

The invariant cross sections for forward charged-hadron production at zero angle in carbon–carbon collisions at a beam kinetic energy of 19.6 GeV per nucleon were measured at the U-70 accelerator in an experiment performed with the aid of a combined spectrometer including beam line 22 and detectors of the modified FODS setup. The beam line rigidity was varied between 7 and 70 GeV/$$c$$. The results are compared with the predictions of the FTFP model and a self-similar solution for nucleus–nucleus collisions.

Broadband terahertz infrared absorption spectra of liquid water are described using the nonstandard Frenkel gas–solid model for water, supplemented by the interconversion of molecules and ions due presumably to the mixed translational–vibrational motion of molecules in liquids. The periods of water molecule retention by hydration and ionic shells are calculated.