Deflection of a relativistic electron beam by means of the pyroelectric deflector is demonstrated experimentally for the first time. The operating principle of the pyroelectric deflector is based on the generation of a strong transverse electric field in a vacuum in the gap between a pair of pyroelectric crystals due to the pyroelectric effect. The experiments on observation of deflection of 7 MeV electron beam for 26 mrad in the transverse electric field with a strength of about 100 kV/cm arising at a variation of the temperature of a pair of pyroelectric crystals in vacuum are described. The possibility for application of the installed sequentially pyroelectric deflectors in pyroelectric undulator for production of undulator radiation by relativistic electron beam without any external high voltage power supply is discussed.

The article deals with the issues of modeling and control of the gas transmission system in non-stationary consumption modes. The topology of the gas transmission network is parameterized in the form of a digraph, with weighted vertices representing the vertices-the drains of consumers, the vertices-the sources of suppliers, transit vertices (compressor or gas distribution stations) and arcs indicating the main parameters that affect the throughput of the system. A hierarchical model of gas transportation system management is proposed, where the upper level is the flow diagram of gas transport, and the lower level simulates the physical processes of gas flow in the pipe section. A procedure for dynamic control in non-stationary consumption modes is developed, which is represented as a sequence of transitions between stationary flow schemes according to the criterion of minimizing their mismatch at neighboring time intervals corresponding to the intervals of constancy of consumption requests, which further reduces the energy costs of changing the flow scheme. The practical value of the research results lies in the possibility of their use while dispatching control.

The article is devoted to investigation of ion generation by tungsten filament in vacuum. Electron and ion currents from tungsten filament at different residual air gas pressures are measured and compared. Dependencies of ion and electron currents from tungsten filament on its supply voltage are measured. Production of ions in the vicinity of the filament is discussed. Prospects of tungsten filament’s application in pyroelectric and piezoelectric pulsed accelerators are discussed.

The conception of operation of the pyroelectric accelerator and X-ray source in pulsed mode is at first proposed and demonstrated experimentally. The pulsed mode became possible due to application of the additional controlled source of electrons in the pyroelectric accelerator. In the proof-of-principle experiment, the power of X-ray radiation in pulsed mode increased one in common quasi-continuous mode in more than two orders of magnitude. Perspectives for further increasing of the power and application of pulsed pyroelectric X-ray source in fast X-ray imaging are discussed.

Results of first experiments with piezoelectric accelerator built on quartz crystals as piezoelectric elements are presented. Accelerating voltage in such quartz accelerator is produced at compression in vacuum of quartz crystals along polar axis. The construction of the quartz accelerator and results of measurements the spectra of X-ray radiation which is produced by electrons accelerated in such accelerator are described. Accelerating voltage in quartz accelerator observed in the experiment is discussed.

The possibility for application of semiconductor element for heating of pyroelectric crystalin a pyroelectric accelerator of charged particles or pyroelectric X-ray generator is at first proposed and demonstrated experimentally. Spectra of X-ray radiation measured at the heating of the pyroelectric crystal LiNbO3 by silicon diode at different pressures of residual gas are presented. Perspectives for application of semiconductor heater in the pyroelectric accelerators and X-ray generators are discussed.

In this work we present the results of the experimental studies of the dependence of the X-ray radiation on the temperature change speed of the lithium tantalate monocrystal in the pyroelectric source of the X-ray radiation. We have found an optimized linear temperature speed change pattern for the pyroelectric crystal designed for generation of the X-ray radiation with enhanced capabilities. The studies that were made open an opportunity to determine the most convenient conditions for generation of X-ray radiation with pyroelectric effect and for development of high-capacity pyroelectric X-ray radiation sources.

The results of an investigation of the passage of 10-keV electron beam through dielectric channels fabricated from ceramic (zirconium dioxide) and pyroelectric crystals (lithium niobate) are presented. The angle of deflection of the electron beam by the channels was measured as a function of the angle of interaction of the beam with the internal walls of the channels. The obtained results indicate the possible prospects of using dielectric surfaces as effective deflectors of accelerated charged particles.

Here we propose the conception of small-size piezoelectric accelerator of charged particles that operates due to the piezoelectric effect at varying mechanical force applied to piezoelectrics in vacuum. The accelerating voltage and the energy of accelerated particles are estimated. In the proof-of-principle experiment we demonstrate the effect of the emission of X-ray radiation at the mechanical compression of piezoelectric ceramics in vacuum. The compression leads to the appearance of charges and potentials on the surfaces of the piezoelectrics and also to the arising of the electric field in vacuum. Electrons are accelerated in the electric field, strike the matter and produce the X-ray radiation. In the experiment, we have observed emission of the characteristic and bremsstrahlung X-ray radiation of energy up to 60 keV due to the compression of piezoelectric ceramics in vacuum. This means that electrons are accelerated in the piezoelectric accelerator up to the energy at least of 60 keV. The agreement of calculated and experimental data confirms the conception. Advantages of the piezoelectric accelerator and possibilities of its development and applications are discussed.

In this letter, we report the observation of fast neutrons generated when a positive acceleration potential is applied to an array of orientated carbon nanotubes, which are used as an ion source. The neutrons with energy of 2.45 MeV are generated as a result of D-D fusion reaction. The dependencies of the neutron yield on the value of the applied potential and residual pressure of deuterium are measured. The proposed approach is planned to be used for the development of compact neutron generators.

Experiments on acceleration of electrons and production of X-ray radiation with use of ceramic piezoelectric transformers installed in vacuum are described and analyzed. The piezoelectric transformer operates at resonance frequency. Electrons are accelerated from the high-voltage electrode of the ceramic piezoelectric transformer toward the grounded target, where they emit bremsstrahlung and characteristic X-ray radiation in the target material. The returning of the charge to the high-voltage electrode is provided due to electrons emitted from a filament installed in the vicinity of the target. It was found that the X-ray yield increases linearly at increasing of the pressure of the residual gas in the chamber within two orders of magnitude up to about 10 mTorr, when the gas discharge around of the piezoelectric transformer arises. Possibilities for application of piezoelectric transformers for production of accelerating voltage in small-size accelerators are discussed.

The results of an experimental study of x-ray generation aided by a ceramic piezoelectric transformer placed in vacuum are presented. X-rays were emitted with the piezoelectric transformer tuned to resonance at about 20 kHz. A characteristic emission peak of a titanium target at energy of 4.5 keV against the Bremsstrahlung background was observed in the measured x-ray spectra. The maximum energy of the x-ray Bremsstrahlung reaches 12 keV. This means that the electrons are accelerated in vacuum in the field of the piezoelectric transformer to at least 12 keV.

Results of experimental investigation for application carbon nanotubes (CNT) array in a pyroelectric X-ray source are presented. It is shown that CNT allows increasing X-ray yield and energy, but the orientation of CNT array should be taken into account since the accidentally oriented CNT array is more efficient. Also, an optimal residual gas pressure condition for the pyroelectric X-ray source with CNT arrays has been found. It has been determined that the maximum of X-ray yield observed at 0.1 mTorr. Effects that lead to an increasing of the X-ray yield and perspectives of the pyroelectric source with CNT arrays are discussed.

The possibility of using PZT-19 ceramic in a pyroelectric x-ray generator is investigated experimentally. Measurements of the x-ray spectra showed the possibility of obtaining on a ceramic surface in vacuum potentials up to 7 kV, which is very low compared with typical similar values for pyroelectric crystals of lithium niobate and tantalate. This feature is due to the significant permittivity of the ceramic. It is shown that the main criterion for picking a ceramic for a pyroelectric x-ray generation could be the maximum value of the ratio of the pyroelectric constant to the permittivity.

DarkSide is a dark matter direct search experiment at Laboratori Nazionali del Gran Sasso (LNGS). DarkSide is based on the detection of rare nuclear recoils possibly induced by hypothetical dark matter particles, which are supposed to be neutral, massive (m > 10 GeV) and weakly interactive (WIMP). The dark matter detector is a two-phase time projection chamber (TPC) filled with ultra-pure liquid argon. The TPC is placed inside a muon and a neutron active vetoes to suppress the background. Using argon as active target has many advantages, the key features are the strong discriminant power between nuclear and electron recoils, the spatial reconstruction and easy scalability to multi-tons size. At the moment DarkSide-50 is filled with ultra-pure argon, extracted from underground sources, and from April 2015 it is taking data in its final configuration. When combined with the preceding search with an atmospheric argon target, it is possible to set a 90% CL upper limit on the WIMP-nucleon spin-independent cross section of 2.0×10−44 cm2 for a WIMP mass of 100 GeV/c2. The next phase of the experiment, DarkSide-20k, will be the construction of a new detector with an active mass of ∼ 20 tons.

Pyroelectric crystals, such as LiNbO3 or LiTaO3 being under influence of a temperature gradient can produce an electric field up to 10(5) kV/cm. It was experimentally confirmed that a crystal installed in a chamber with a residual gas pressure of about 1 mTorr could be used to generate X-Ray radiation with an energy up to 100 keV The same setup could be used to generate s 2.45 MeV neutrons if the target is deuterated and residual gas is D2. Due to such properties as On/Off mode of operation and the absence of radioactive materials, pyroelectric neutron generators seem to be a promising tool for calibration of neutrino and dark matter and other low background detectors. We propose the application of the controlled pyroelectric neutron generator for calibration of such detectors.

The results of experimental studies of the spectral composition and yield of X-ray radiation from pyroelectric sources with cone-shaped targets are presented. A distinct maximum of the yield as a function of the distance between the pyroelectric crystal and the target is found for a single-crystal pyroelectric source with a truncated cone target. It is demonstrated in the experiment involving a source with two pyroelectric crystals and a cone-shaped target that the X-ray parameters are virtually independent of the direction of temperature change in the crystals.