The radionuclide 111In is one of the widely used radionuclides in diagnostic nuclear medicine. Research on its production has been carried out since the second half of the last century. For commercial purposes, 111In is produced in proton or alpha particle induced reactions on cadmium or silver targets [1, 2]. However, in recent years, various activation methods have been proposed to obtain...
We present a novel Python tool for the analysis of Geant4 simulations that enhances our understanding of coherent phenomena occurring during the interaction of charged particles with crystal planes. This tool compares the total energy of particles with the potential energy inside crystal channels, enabling a complete examination of coherent effects. By tracking and tagging the dynamics of each...
A new high-quality positron 530 MeV beam has been installed at the Institute for Nuclear Physics of the University of Mainz using the features of the MAMI accelerator. Positrons are created by pair conversion of bremsstrahlung, produced by a focused 855 MeV electron beam of MAMI in a 10 µm thick tungsten self converter target, and energy selected by an outside open electron beam-line bending...
A compact accelerator-based neutron source has been proposed and created at the Budker Institute of Nuclear Physics in Novosibirsk, Russia [1]. An original vacuum insulated tandem accelerator (VITA) is used to provide a dc proton/deuteron beam. The ion beam energy can be varied within a range of 0.1–2.3 MeV, keeping a high-energy stability of 0.1 %. The beam current can also be varied in a...
Development of new materials and instrumentations for detection of charge particle beams and measuring their parameters are very topical in modern accelerator physics [1]. Cherenkov effect is well-known phenomenon that can be used for beam diagnosis. Commonly, diamond crystals is considered to be used as Cherenkov radiators for this purposes since this material has high resistance to radiation...
The X-ray source based on parametric X-ray radiation (PXR) has been developed and employed for users studies at the Laboratory for Electron Beam Research and Application (LEBRA), Nihon University. The X-ray energy of the LEBRA-PXR source is limited to 34keV in the case of using Si(220) as a radiator. Samples containing elements heavier than cesium such as lanthanoid are difficult to treat for...
Bent crystal have been widely used to deflect high energy particles in the last decades and the precise knowledge of their properties has been crucial for their deployment in particle accelerator complex. Based on a time-reversal approach to the channeling effect, the UA9 collaboration is investigating the possibility to merge two particle beam impinging with specific angles on a bent crystal....
Bent crystals, through channeling effects, can induce coherent deflection of charged particles, making them invaluable tools for controlling particle beams. This research focuses on the fabrication, of bent crystals tailored for spin precession studies at the LHC.
The twisted photon is a state of a free electromagnetic field with the certain energy, longitudinal projection of the momentum, projection of the total angular momentum and helicity. Various schemes of production of the twisted photons have been proposed recently. The undulators [1-5] and free electron lasers [6-8] are used in these schemes. High energy twisted photons can also be generated by...
When a fast charged particle induces polarization currents in a medium, these currents become a source of polarization radiation. Polarization radiation Vavilov-Cherenkov, transition, Smith-Purcell and other radiations. Although polarization radiation has a microscopic nature, its microscopic description is not well developed.
Here we present the preliminary results of microscopic theory of...
In this study, a series of experimental samples were produced using the fused filament fabrication technique. The set comprised dielectric wafers printed from a variety of polymers, including polyethylene terephthalate glycol (PETG), polylactide (PLA), acrylonitrile butadiene styrene (ABS), high impact polystyrene (HIPS), styrene-acrylonitrile (SAN) and PLA with differing concentrations of...
The following paper will display the fundamental ChDR studies which have been undertaken using the BPM prototype, presenting the design of the BPM itself whilst focusing on the process of optimising the maximum signal for 500 nm narrowband ChDR. Data acquisition for the examination of ChDR signal decay has stemmed from impact parameter scans where a particular assembly or beam parameter is...
The report presents the measurement results of the characteristics of optical Cherenkov radiation (ChR) in comparison with traditional transition radiation (TR). The experiment was carried out using an electron beam from the LINAC200 accelerator with an energy of 18 MeV. The radiation was detected at an angle of 90 degrees relative to the electron beam using the TAMRON lens with a focal length...
The problem of coherent X-ray radiation formed in crystalline undulator (CU) by positron bunch with modulated density is solved. The CU parameters are calculated, the choice of which provides coherent radiation of the positron bunch (with parameters of LCLS) modulated in the SASE FEL process. If modulation depth is not too small, then an X-ray photon beam is formed, more powerful and...
Thomson backscattering of a laser beam on relativistic electrons is one of the most promising ways to generate bright quasi-monochromatic X-ray radiation. To achieve a high luminosity of such a source, it is possible to increase the intensity of the initial beams, but this will lead to nonlinear effects, which significantly degrade the radiation spectrum. Another approach is to optimize the...
Computed tomography (CT) is a widely used method that provides huge opportunities for imaging the internal structure of different samples without disturbing their structures. During a CT scan, X-rays pass through a sample and detectors measure the radiation intensity after their interaction with this sample. The images directly obtained during the X-ray CT scan are two-dimensional projections...
The work investigated the features of the formation and movement of a superdense flow of fast electrons, formed under the action of a polarized high-power laser pulse on the crystal surface, inside a crystal. It is shown that, at a certain orientation of the laser pulse, repeatedly planar channeling of these electrons occurs, with their energy reaching relativistic values.
The report also...
The Muon Collider is an ambitious proposal to push the boundaries of high-energy physics beyond current limitations. By exploiting for the first time unstable fundamental particles such as muons, this collider combines the precision of electron/positron collider and the higher energy reach of hadron colliders.
Bent crystal had proven great utility for manipulation of ultrarelativistic beams...
There are not many more effective methods for researching the structure of the universe. However, there are opportunities that will allow to adjust some circumstances. First of all, there is an opportunity to determine the distribution of extragalactic sources with the help of quasar studies, to have more accurate data. Quasars being the brightest sources in the Universe, they can be observed...
high-energy physics and astrophysics, yet their crystalline structure and lattice orientation are often overlooked in detector design. However, the electromagnetic field experienced by particles impinging on a crystal at small angles relative to a lattice axis can significantly influence interaction mechanisms. Specifically, for electrons or photons with energies of O(10 GeV) or higher...
The efficiency of planar channeling for positive particles is limited by nuclear scattering when particles approach too close to the nuclei within the atomic planes. To mitigate this effect, a solution was proposed in 2007 [1], involving the creation of an optimized interruption in the crystal lattice at a strategic position before nuclear dechanneling can occur. Implementing this solution...
Nematic single crystals (NLC) find wide application in creating various optical devices, where the functioning is based on effects related to the change in orientation of the optical axis or the disruption of optical homogeneity of the crystal in electric, magnetic, and acoustic fields. The development of fundamentally new indicator devices based on electro-optic effects in LCs simul¬taneously...
Recent years have witnessed an intense investigations of Cherenkov diffraction radiation (ChDR) appearing when a fast charged particle moves in the vicinity of and parallel to a dielectric interface. This is a member of polarization radiation family, because the radiation arises as a result of dynamic polarization of a medium. The ChDR properties are sensitive to various beam parameters...
Plasma acceleration is a novel technique for a large variety of applications, including radiation sources of new generation. X-ray sources based on betatron radiation from plasma accelerators hold promise as compact, innovative and highly accessible solutions for radiation users. The key feature that makes these sources unique, lies in the shortness of the pulses delivered, falling in the...
The results of theoretical investigation of the spectral and angular distributions of the radiation generated by a charged particle crossing a ball of dispersive material in vacuum, are presented. Previously, in the case of a non-dispersive dielectric ball it was shown that strong peaks appear in the spectral distribution of the radiation intensity for certain values of the problem parameters....
In this work, the interaction potentials of electrons with the main crystallographic planes (100), (110), (101), (001) and (111) in crystals of tetrafluoroaluminates KAlF4, TlAlF4, RbAlF4 and NH4AlF4 were calculated. For beams of weakly relativistic electrons with Lorentz factors $\gamma$ = 10, 20, 30 and with different angular dispersions, the features of spontaneous short-wave radiation...
The investigation methods of photon and ion channeling can give important information about the zone structure and the confinement potential character of the investigated quantum dots (QD). [1,2]. In particular, it is essential at the description of the physical processes in QDs with complicated geometry when the problem of quantum confinement of the particles is fundamentally important for...
The Future Circular electron-positron Collider (FCC-ee) is being designed to reach energy and luminosity frontiers for lepton colliders. This requires managing very high-intensity lepton beams, with stored beam energies up to 17.5 MJ. Therefore, a beam collimation system is essential for safely disposing of unavoidable beam losses. Unique challenges for the collimation system design need to be...
On the basis of exact Lienar-Wichert equations a method is developed that determines parametric expressions of the electromagnetic field of a charged particle moving in vacuum on one-dimensional curve in space. Specific parameterization allows to overcome the problem of solving the retardation equation. We call the defined field on a one-dimensional curve the footprint of Lienard-Wiechert...
In order to perform full simulations of crystal-based extraction from an accelerator, a combination of simulation codes for beam dynamics in an accelerator and channeling physics in crystals is required. Our solution exploits the Beam Delivery Simulation (BDSIM) [1], an extensive library that contains thick lens accelerator tracking routines and a wide variety of accelerator components and...
A formula for the spectral distribution of intensity of radiation from a system of gap-separated spiral undulators is derived. It is found that the form of spontaneous radiation line is changing, viz., it narrows, if the gap between the undulators increases. As the gain factor of the stimulated radiation depends on the derivative of the form of the line, then, as shown in this work, at least...
Inverse Compton scattering [1, 2] is a promising instrument for engineering of a bright, compact and versatile X-ray source: with dimensions being significantly smaller, the brightness of this source is comparable with that of synchrotron radiation. Here we report on the creation of a new C++ module for inverse Compton scattering simulation and its implementation into Geant4 [3]. The module...
Development of advanced intense and reliable sources of charged particle beams is a direction within accelerator physics on its own right. By changing the temperature of Lithium Tantalate (LiTaO3) single crystal at moderate vacuum conditions leads to generation of strong electric field. The uncompensated polarization during the heating or cooling of the crystal causes the ejection of electrons...
The quantum mechanical problem of the angular distribution of particles at the exit from a curved crystal is considered. Preliminary results have shown that the addition of a some perturbation to the average atomic potential leads to a deformation of the angular distribution function of channeled particles at the exit from a bent crystal. But the angular distribution function of channeled...
It is known that the mosaic nature of the crystal significantly affects the characteristics of the radiation of fast electrons, and the degree of this influence depends on the radiation mechanism. The intensity of radiation at the Bragg angle increases sharply due to the additional contribution of diffracted real photons of transition and bremsstrahlung radiation [1], peaks in the spectra of...
The concept of a pyroelectric accelerator entails a compact device that does not require an external high-voltage circuit or the use of hazardous materials. This enables the generation of an electron flow within a narrow energy range, which converges at a certain distance from the surface of the pyroelectric crystal when its temperature changes in a vacuum. Utilizing a target with a hole...
Crystalline based undulators are breakthrough devices for the development of novel gamma-ray Light Sources (LS). These devices, operating at photon energies from 100 keV up to GeV, represent a new approach for gamma ray production. Taking advantage of the channelling phenomena, it is possible to expose of an oriented crystal (linear, bent or periodically bent) to the relativistic particles...
Recent advancements in radiobiology focus on the effects of ionizing radiation on biological systems, with a critical emphasis on understanding how radiation impacts DNA, as structural breaks in DNA are a primary cause of cellular death. Enhancing the efficacy of cancer treatments by combining radiation therapy with other modalities, such as chemotherapy and phototherapy, can mitigate the side...
Vertically aligned carbon nanotubes (VACNTs) are best candidate as emitters because of their high ordered structure, directional sensitivity and superior field emission performances. To understand the effective relation between field enhancement factor and surface morphology, we provide a protocol to quantitively characterize the topographic properties of nanotubes. After an efficient...
The pursuit of compact, high-brightness particle and radiation sources has driven significant advancements in laser technology, emphasizing improved efficiency and repetition rates [1]. These developments have led to the emergence of a new generation of ultrafast high-power laser systems operating at high repetition rates worldwide.
In 2024, a new high-power laser facility called "I-LUCE"...
Unlike in a vacuum undulator, an undulator containing a dispersive medium forms a line shape of soft photons. The energy of these photons is determined by the oscillation frequency of an ultra-relativistic charged particle and the plasma frequency of the medium, when the energy of the particle greatly exceeds the threshold energy for radiation formation. The line shape of the spontaneous...
The work considers the mechanism of self-controlled autocollimation of a beam of positive ions during their channeling in crystals, which can lead to a significant reduction in the angular dispersion of the ions beam. The autocollimation process is associated with elastic ion scattering and stepwise transfer of the transverse energy E_\perp of a channeled ion to groups N \approx \Lambda / 2...
Compact, efficient, and high-quality plasma wakefield-accelerated free electron lasers (FELs), betatron sources, and novel synchrotron radiation (SR) coherent sources are under development to meet the latest experimental and technological demands [1, 2]. All new sources need small, low-loss optical parts that can focus, condense, monochromatize, filter, and/or focus radiation, as well as...
Accelerators of charged particles are powerful tools used in many fundamental researches and applied tasks. Compact accelerators are currently widely employed for pretesting and proof-of-principle experiments for MegaScience projects, as well as for applied purposes. In particular, electron accelerators allowing generating of few MeV beams are used for testing of different techniques of beam...
An analytical model for the volume capture of high-energy positive particles into planar (111) channels of a silicon single crystal is proposed. Under the assumption that the cause of particle capture is multiple scattering, the capture probability is found. Channeling of trapped particles is also considered. Comparison of calculations with experiment is performed. Results of the study will...
Permanent Staff Personnel and Associated Personnel of INFN-LNF are setting up the local Astrophysics and Cosmology Team (ACT). The INFN-LNF ACT joined in 2023 the initial development phases of one of the forthcoming next-generation cosmology space-borne probes. The INFN-LNF ACT constituted an Integrated Test Facility (ITF), which is being instrumented in a dedicated space and will also make...
The results of an experimental study of the spectral angular distribution of coherent transition and Cherenkov radiation in the sub–terahertz frequency range are presented. As targets, a thin silicon plate with an aluminium coating and a cylindrical Teflon resonator were used. The AREAL linear accelerator, with an energy of 3.6 MeV and located at the CANDLE Synchrotron Research Institute in...
Coherent TR (CTR) is generated when the radiation wavelength is comparable to or longer than the bunch length. In that case, all particles emit radiation more or less in phase, and the radiation intensity is proportional to a square of the number of particles in a bunch. However, if we have a sequence of bunches (a train) separated by a fixed distance from one another, the radiation is...
The results of experimental observations of X-ray transition radiation (with energies ranging from 10 to 200 keV) from a stack of thin aluminum foils (10-20 µm thick), separated by layers of either Teflon or air (50-100 µm thick), are presented. The experiment was conducted using the electron beam of the DESY Test Beam Facility at energies of 1.0 and 2.4 GeV. The spectral-angular distribution...
A new method of diffraction microradiography of single crystals has been proposed and implemented, based on increasing the resolution of X-ray topographic patterns. A special device has been developed, created, and tested that makes it possible to scan synchronously the slit for transmitting separate parts of the X-ray diffraction pattern and X-ray film with a predetermined speed ratio. The...
As international experience shows, advances in modern science and technology in designing and introducing earthquake early warning systems (EEWS) in many countries significantly improved the effectiveness and feasibility of short-term early warnings of upcoming earthquake shakes and the use of territorial EEWSs. Despite the universal recognition of the EEWSs’ efficacy in many countries and...
The article discusses the prerequisites for the implementation of stimulated laser generation of short-wave (including X-ray) radiation based on a system of fast electrons channeled in a standing light wave. It is shown that considering all the features of the quantum states of such particles makes it possible to determine the conditions for implementing such short-wave lasers. To optimize...
In the paper, calculations were made on resonance capture of valence electrons by non-relativistic protons channeled in carbon nanotubes. The probabilities of the formation of hydrogen atoms with such capture were calculated using the non-stationary perturbed theory. Ionization processes are also analyzed and it is shown that in a certain range of speeds a sufficiently high yield of neutral...
First results on the use of polycapillary optical systems will be reported.
Using a 530 MeV positron beam from the Mainz Microtron MAMI and a bent silicon crystal, we successfully manipulated positron trajectories through planar channeling and volume reflection. This experiment revealed detailed structures in the angular distribution of channeled charged particles within bent crystal planes. Our findings align with simulations, enhancing our understanding of...
In the proposed model for the anomalous (with negative values for dielectric constant) region of consideration with the assumption of the formation of dipole-domain cells (DDC) in the substance, the state of the substance is characterized by the parameter of the degree of dominant orientational ordering DDC. In the model approximation, matter is considered as a continuous homogeneous medium...
The results of theoretical investigations of the spectral distributions of the radiation generated by an electron rotating around a ball of a dispersive matter, in vacuum, are presented. Previously, for non dispersive dielectric ball was shown that for certain values of the problem parameters, at certain harmonics, the electron may generate radiation field quanta exceeding in several dozens...
We investigate the features of surface polaritons generated by a charged particle coaxially circulating inside a cylindrical waveguide immersed in a homogeneous medium. The corresponding surface waves are emitted on the eigenmodes of the cylindrical waveguide in the spectral range where the real parts of the dielectric permittivities for the cylinder and surrounding medium have opposite signs....
Laser-plasma ion acceleration is a well established field of research, with several mechanisms being exploited to produce particle beams with high energy and short bunch lengths.
One of these techniques is radiation pressure acceleration (RPA), which turns into collisionless shock acceleration (CSA) when thermal effects become relavant.
Scaling laws show that both the vector potential of...
Here we report on the results of computer simulations of a calorimeter system for charged particle detection based on Cherenkov radiators with a profiled end-face. We performed simulations in the Geant4 package [1], which is the leading simulation toolkit in high-energy physics, accelerator physics, medical physics, and space studies. We demonstrate that profiled end-faces of Cherenkov...
Current limitations in the field of undulators include the inability of state-of-the-art magnetic undulators to achieve periods shorter than a few centimeters. To overcome these limitations, Crystalline Undulators (CUs) consist of periodically bent crystals [1] in which channeled electrons or positrons follow the bending of the crystalline planes must be developed. These CUs aim to generate...
Smith-Purcell radiation (SPR) is a widely known effect considered as prospective for ultra-relativistic electron beam diagnostics. Yet, the applications of this effect are not limited to physics of high-energy accelerators: nowadays, it is investigated as the way for generation of radiation from plasmonic and meta-structures.
In this report i consider theoretically SPR from the periodical...
We present the theory of interaction between a metasurface and an electron with non-zero orbital angular momentum (OAM). The metasurface consists of meta-atoms – subwavelength particles – located at the nods of 2D lattice with periods comparable to the wavelength of radiation. Previously we constructed the theory of SPR from such a metasurface for an electron with zero OAM [1, 2]. We discuss...
Positron sources are key elements for future lepton colliders, such as FCC-ee. In order to generate high intensity and low emittance positron beams, two alternative approaches based on oriented crystals have been proposed with respect to the conventional method, which relies on the electron into positron conversion in a thick amorphous target [1,2]. In this contribution, we present the...
In this work, as a result of the numerical solution of the system of kinetic equations for weakly relativistic positrons channeled both along the basal and prismatic planes and along the c-axes in the hexagonal crystals under study, the populations of quantum levels of transverse energy are found as a function of the longitudinal coordinate. The widths of levels and the probabilities of...
Two 4th generation synchrotron radiation sources will be in Russia soon. One of it is 3 GeV SKIF in Koltsovo and the another one is 6 GeV SYLA in Protvino (former SSRS-4 and USSR). Both were digned for equlibrium horizontal beam emittance is about 70 pm. The current activities on the SYLA project will be presented. As in most similar state-of-the-art facilities, electron beams will be injected...
Recent advances in accelerator physics have expanded the array of techniques available for manipulating charged-particle beams. The successful implementation of adiabatic trapping and transport of beams in resonance islands at the CERN Proton Synchrotron has enabled multiturn extraction. The successful installation of bent crystals in the CERN Large Hadron Collider has enhanced the collimation...
Semiconductor nanoplatelets (NPL) are quasi-two-dimensional systems occupying an intermediate position between quantum wells and quantum dots [1]. NPL is considered a promising area for the role of an elementary base for semiconductor devices of a new generation and various applications including ion channeling, sensing, green energetics, etc. [2-5].
The single-electron spectrum in NPL...
It is shown that if the screening function of an atomic potential may be described within the Thomas-Fermi approximation, the corresponding continuous potential for planar channeling to a good accuracy reduces to a truncated Coulomb potential. The sum of two displaced Coulomb potentials also accurately approximates thermal continuous potentials for (110) Si, Ge, W and (111) Ge oriented...
Solid-state plasma wakefield acceleration has recently garnered attention as a viable alternative for achieving unprecedented ultra-high acceleration gradients on the order of 1 TV/m or beyond [1, 2]. In this context, recent advancements in nanofabrication techniques [3] have opened up the possibility of creating structured plasmas with inhomogeneous properties. For instance, the utilization...
Simulation of a crystal-based positron source requires sophisticated modeling of the trajectories of electrons and positrons in a heavy crystalline material, such as a tungsten crystal. This also includes accounting for their multi-photon radiation and ionization energy losses. The models [1-3] for charged particle motion in an averaged atomic potential, as well as their radiation using the...
