This paper presents the results of the development and implementation of fast wire scanners based on servomotors with a resolver and standard control electronics at a speed of 16 m/s at the U-70 IHEP accelerator. Profilometers are designed to measure the density distribution of proton and carbon beams in the horizontal and vertical planes. The motors of scanners are controlled by servocontrollers through the Copley Motion Explorer CME2 software shell. The beam profile is recorded using scintillation detectors. The beam profile and dimensions were processed using a program developed in the LabVIEW environment. To determine the beam revolution frequency, the fast Fourier transform and the integration of the measured input signal over a given number of beam revolutions are used. The beam parameters are given for a wide range of particle intensities and energies.

In view of the successful experience in the generation of pion and kaon secondary beams using a focusing crystal, it has been proposed to build at the U-70 accelerator a new-type channel of secondary particles that does not consume electric power. It has been shown experimentally that an extraction septum magnet can be protected from radiation by applying a multistrip crystal device through current septum shadowing by the crystal that involves the bulk reflection regime for the deflection of particles. The listed applications of crystals are novel in the world practice with accelerators.

Studies on the steering of particle beams using channeling in aligned bent crystals have been performed at IHEP for many years. Different types of extraction schemes with bent crystals and technical equipment have been developed for experiments to test new crystal devices and to study beam collimation processes. A special apparatus has been designed to control the crystal extraction system. In this article, we describe the crystal devices and in-vacuum goniometers, the beam diagnostic tools (intensity and profile measurements), and the beam feedback system.

Works on the steering of particle beams using channeling in aligned bent crystals have been carried out at IHEP over a number of years. Comprehensive theoretical and experimental studies have led to the creation of actually operating systems on the U-70 accelerator. In particular, a slow proton beam extraction with unprecedentedly high parameters, an extraction efficiency of about 85% at a beam intensity of 10[Formula: see text] particles per cycle, has been realized on U-70 using particle channeling in short bent crystals. In recent years, successful experiments on the extraction of carbon ions were performed. At present, crystal elements are used in regular U-70 runs and provide half of the particle beams for physical experiments. Here, we summarize the results of this unique experience in the world practice of accelerators and outline its prospects.

Works on the formation of particle and radiation beams using particle channeling and reflection in oriented crystals have been carried out at IHEP over a number of years. Comprehensive theoretical and experimental studies have led to the creation of actually operating systems on the U-70 accelerator. In particular, a slow proton beam extraction with unprecedentedly high parameters, an extraction efficiency of about 85% at a beam intensity of 10 12 particles per cycle, has been realized on U-70 using particle channeling in short bent crystals. Experiments to implement the method of particle reflection in crystals for beam extraction and collimation have been carried out on U-70. At present, crystal elements are used in regular U-70 runs and provide half of the particle beams for physical experiments. We summarize the results of this unique experience in the world practice of accelerators and outline its prospects.

Phenomenon of the deflection of charged particle beam due to channeling in a bent crystal is good investigated and successfully applied for extraction of the beam in high-energy accelerators, at the energies of about 10 GeV and higher. However, a significant practical interest presents the problem of deflection and extraction of charged particles with energies below 1 GeV, for example, production of ultrastable beams of low emittance for medical and biological applications. That’s why two novel crystal techniques, namely: thin sequential straight crystal targets, and array of short bent crystal strips were investigated in this report as elements for extraction of the beam from U-70 accelerator. Experimental results were obtained for extraction of 1.3 GeV protons.

Extraction and collimation of the 50-GeV proton beam with a bent silicon crystal at the U-70 accelerator of the Institute for High Energy Physics (Protvino, Russia) was investigated. Until recently, proton beam extraction (and collimation) from accelerators has been effected using crystals with the (111) or (110) plane orientation, when the beam propagates far from the crystal axes. In the described experiment, the silicon crystal was oriented so that the proton beam was incident on it near the 〈110〉 axis. Under these conditions, a part of the beam was deflected by the crystal owing to the dynamic chaos phenomenon. The maximum beam extraction efficiency was as high as ~80%.

This paper presents the mechatronic design of a fast wire scanner based on a servomotor. The design of the wire scanner is motivated by the need to measure the transverse profile of the high power proton and carbon beams at the IHEP U-70 accelerator. This paper formulates the requirements to the fast wire scanner system for the high intensity proton beam at the U-70 accelerator. The results on the design of electro-mechanical device for the wire scanner with a wire traveling speed 10–20 m/s are presented. The solution consists in a brushless servomotor and standard motor control electronics. High radiation levels in the accelerator enclosure dictate the use of a resolver as the position feedback element.

Different crystal devices are described, which provide an extraction and splitting of beams for a long period of time at the U-70 accelerator of IHEP. The modes of channeling and volume reflections in the bent crystals are used for these tasks. In regular accelerator runs crystals produce the particle beams in a wide range of intensity, from 10(6) up to 10(12) particles in a cycle. Novel crystal techniques suitable for charged particle beams deflection and focus as well as photon generation are presented also.

The efficiency of the deflection of 50-, 15-, and 1.3-GeV proton beams by means of planar channeling in a bent silicon crystal has been compared to that by means of the stochastic mechanism of the deflection of charged particles by the bent crystal. The deflection of protons at single passage through the crystal has been simulated. The results of the experiment on the deflection of a circulating beam at the U-70 accelerator (Institute for High Energy Physics, Protvino, Moscow region) are presented. It has been shown that the efficiency of the stochastic deflection mechanism increases with a decrease in the energy, whereas the efficiency of the planar channeling for deflection decreases.

It has been recently proposed using a bent crystal with a declining curvature instead of a uniformly bent crystal in order to improve extraction and collimation of the circulating beam in the accelerator. Variable curvature crystal devices developed to implement this idea are described. Curvature values measured along the crystal plate are presented. It is shown that focusing of high energy beams can also be focused using the developed devices.

Bent silicon monocrystals are used today in the planar channeling mode for beam extraction and collimation at large accelerators. Volume reflection is more efficient than channeling, though it has a small deflection angle. A device for repeated deflection of a proton beam using a few bent silicon strips in the reflection mode is described in this paper. Sequential silicon strips on the surface of a thick plate are bent by internal stresses in the crystal material resulting from the Twyman effect. As shown by the Monte Carlo calculations, this method for deflecting the beam is optimal for the teraelectronvolt energy range.

The report presents an overview of the results of IHEP activity obtained during 1987-2012 in the field of studying and using bent crystals to steer high-energy particle beams. The hardware installed to study crystal beam splitting, collimation and extraction is described. It has been shown that the developed crystal deflectors are capable for sustaining long-term operation to deliver high-energy extracted beams for fixed-target physics. The first results on extraction of 24.1GeV/nucleon carbon ions are also presented.

The report presents an overview the results of IHEP activity in the field of study and using bent crystals to steer high-energy proton and ion beam obtained during 2010-2012. The hardware installed to study crystal collimation and extraction is described. A new dedicated beam transfer line was arranged to study the performance of crystals. It has been shown that the crystal deflections developed are capable of sustaining long-term operation to deliver high-energy extracted beams for fixed-target physics. Experience with practical applications of bent crystals are outlined. First results on the extraction 24.1 GeV nucleon carbon ions are also presented.

In the experiment the efficiency of the 50 GeV proton beam extraction from accelerator by means of a bent crystal as a function of crystal orientation was measured. This allowed one to make a comparative analysis of efficiencies of high-energy protons deflection by different crystal atomic planes with different values of the electrostatic field. The results of simulation of high-energy protons deflection by means of crystal atomic planes and crystal atomic strings are also presented in the article. In the case of planar channeling the simulation shows a good agreement with experimental data. In the case of proton motion in the regime of stochastic scattering by bent atomic strings the simulation shows that angles of particle deflection are much greater than the critical channeling angle.