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The investigation of transverse beam phase space parameters behavior along the accelerator is important for proper accelerator tuning. At INR RAS linac transverse emittance and Twiss parameters are reconstructed from beam profile measurements with quadrupole scan technique at several measurement points along the accelerator. Profile treatment is performed with ordinary transverse profiles method and tomographic reconstruction method. Various experimental data is presented. The comparison of the results obtained by the two methods is done. Features of beam dynamics simulation based on the data from these methods are discussed., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

A longitudinal charge distribution in beam bunches, so-called bunch shape, is one of the most important and difficult to measure characteristics of a beam in ion linear accelerators. Despite the variety of approaches only the methods using low energy secondary electrons emitted, when the beam passes through a thin target, found practical application. The most common beam instrumentation, based on this method, became Bunch Shape Monitor developed in INR RAS. The monitor provides direct measurements of bunch shape and bunch longitudinal halo, allows to carry out such complex diagnostic procedures as longitudinal emittance measurements, amplitude and phase setting of accelerating cavities and control of bunch shape evolution in time to check the overall quality of longitudinal tuning of the accelerator. The principle of the monitor operation, design features, ultimate parameters and limitations are discussed. Several modifications of the monitor with implementation peculiarities are described as well as lots of measurement results at different ion linacs with a variety of beam parameters. New challenges for bunch shape instrumentation to satisfy demands of forthcoming linacs are also characterized., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

A three grid energy analyzer of slow secondary ions with a twin analyzing grid is described. The analyzer has cylindrical geometry and Pi angle for recording of the slow ions. The analyzer has been used for measurements of degree of space-charge compensation (SCC) of a pulsed hydrogen ion beam with energy of 400 keV and peak beam current of 60 mA. Results of the measurements are presented and compared with theoretical estimations based on model in which the SCC degree is limited by heating of electrons in collisions with fast ions of the beam., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

During the last decade, instruments of machine learning are gaining popularity in accelerator control systems. One of these instruments is decision support system (DSS) that is already successfully used in other fields of science. In this article a motivation for implementation of such system for INR RAS linac tuning is discussed. Concept of developed DSS is presented. Changes in INR RAS linac data acquisition system essential for future DSS operation are proposed., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

Measuring of the parameters of the transverse phase portraits is crucial for beam dynamics. A method of tomographic reconstruction is implemented at INR RAS linac as an alternative to already existing quadrupole variation method. In this work new feature of disturbing online measurements of phase portrait parameters and important experimental results are discussed. Comparison of tomographic method with quadrupole variation method is presented., Proceedings of the 9th International Beam Instrumentation Conference, IBIC2020, Santos, Brazil

Multianode gas counter is used as a detector for low intensity proton beam diagnostics at INR RAS linac. The device consists of ionization chamber to measure beam current and two proportional chambers, based on stripe geometry, to measure beam profiles. The data is processed with Labview software. The models and methods predicting operational characteristics of the counter in ionization and proportional mode are presented. An analytical model of recombination was tested to predict the saturation voltage for ionization mode. Beam test results and operational characteristics of the counter are presented as well as results of investigations of counter degradation under the beam. A new design of a gas filled counter is also discussed., Proceedings of the 9th International Beam Instrumentation Conference, IBIC2020, Santos, Brazil

The new proton irradiation facility to study radiation effects in electronics and other materials has been built in INR RAS linac. The range of the specified intensity from 10⁷ to 10¹² protons per beam pulse is covered with three beam diagnostic instruments: current transformer, phosphor screen and multianode gas counter. The peculiarities of the joint use of the three instruments are described. The experimental results of beam parameters observations and adjustments are presented., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

Two Bunch Shape Monitors have been developed and fabricated in INR RAS for European Spallation Source linac. To fulfil the requirements of a 4 ps phase resolution the symmetric λ-type RF-deflector based on the parallel wire line with capacitive plates has been selected. Additional steering magnet to correct incline of the focused electron beam is also used. Limitations due to space charge of the analysed beam and due to external magnetic fields are discussed. The results of the laboratory tests of the monitors are presented., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

The CERN Linac4 has been successfully commissioned to its nominal energy and will provide 160 MeV H⁻ ions for charge-exchange injection into the Proton Synchrotron Booster (PSB) from 2020. A complete set of beam diagnostic devices has been installed along the accelerating structures and the transfer line for safe and efficient operation. This includes two longitudinal Bunch Shape Monitors (BSM) developed by the Institute for Nuclear Research (INR, Moscow). Setting-up the RF cavities of Linac4 involves beam loading observations, time-of-flight measurements and reconstruction of the longitudinal emittance from phase profile measurements. In this paper the BSM is presented along with some results obtained during accelerator commissioning, including a comparison with phase measurements performed using the Beam Position Monitor system., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

Bunch Shape Monitor with three changeable deflectors was designed and manufactured for UNILAC, CW LINAC and proton linac of GSI-FAIR project. The length of BSM RF-deflector for UNILAC was large, that increased the influence of external mechanical vibrations on the BSM operation. The model for mechanical and electrical analysis of BSM RF-deflector and design solutions for vibration damping are presented., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

INR RAS linear accelerator is a high-intensity accelerator, mostly used for isotopes production and neutron experiments. However low-intensity beam research is also presented at INR linac and requires appropriate diagnostics, such as luminescent diagnostics, which is implemented at a new proton irradiation facility. Pros and cons of the diagnostic system, operational characteristics and different experimental beam tests are discussed., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

Bunch Shape Monitor was developed and tested in INR RAS for The Facility for Rare Isotope Beams to fulfil the requirements of a half a degree phase resolution for 80.5 MHz FRIB operating frequency. The configuration of the λ/4-type RF-deflector based on the parallel wire lines with the shorting jumper and capacitive plates was selected. Special dual correcting magnet is foreseen to compensate a possible influence of external magnetic fields. Peculiarities of the design and development process are described. Results of laboratory tests are presented., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

In recent years several Bunch Shape Monitors were designed for new modern ion linacs, such as Linac4 CERN, Proton and CW-linac FAIR GSI, FRIB MSU, ESS ERIC. Each of these accelerators has its own requirements for a phase resolution, mechanical design and operating conditions of the monitor. An overview of the most interesting design and operation features of different monitors is presented. Some results of laboratory tests and on-site beam measurements are discussed., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

Proceedings of the 9th International Particle Accelerator Conference 9th International Particle Accelerator Conference, IPAC2018, Vancouver, Canada, 29 Apr 2018 - 4 May 2018; JACoW Publishing, Geneva, Switzerland 2091-2094 (2018). doi:10.18429/JACOW-IPAC2018-WEPAK006, The existing GSI accelerator will become the injector for FAIR. To preserve and enhance the current experimental program at UNILAC, a new Linac is under development, which shall run in parallel to the FAIR injector, providing cw-beams of ions at energies from 3.5 - 7.3 MeV/u. For this cw-Linac a superconducting prototype cavity has been developed and was first operated with beam in summer 2017. The resonator is a cross-bar H-structure (CH) of 0.7 m length, with a resonant frequency of 216.8 MHz. It has been installed behind the GSI High Charge State Injector (HLI), which provided 10⁸ MHz bunches of 1.4 MeV/u Ar⁶⁺/9+/11+ ions at a duty cycle of 25 %. Due to the frequency jump and small longitudinal acceptance of the CH, proper matching of the HLI beam to the prototype was required. The bunch properties of the injected beam as well as the effect of different phase- and amplitude-settings of the cavity were measured in detail with a bunch shape monitor (BSM) fabricated at INR, Moscow, while the mean energy was analyzed by time of flight method. In this contribution, the bunch shape measurements are described and the capabilities of the used BSM measurement principle are discussed., Published by JACoW Publishing, Geneva, Switzerland

Beam Cross-Section Monitors implemented at INR RAS proton linac provide an efficient non-destructive registration of real 2D beam cross section, beam position and profiles, phase space ellipses reconstructed from profiles data as well as real-time evolution of these parameters in the entire range of beam energies and intensities. Features of the monitor's design and image processing system are described. Measurement accuracy and precision analysis is discussed. A variety of available experimental results are presented., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

A new proton irradiation facility to study radiation effects in electronics and different materials was constructed at INR RAS linac. The beam intensity range is 10⁷-10¹² protons per separate pulses up to 1 uA of average beam current. The energy is adjusted by switching on/off the fields in accelerating cavities and with energy degraders in the range 20-210 MeV. Features of the facility development, in-air operation, diagnostics system, as well as experimental results of beam adjustment and test irradiation are presented., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

In 2015 the experimental complex beam lines of INR linac were upgraded. There is a need to study beam dynamics in these lines. The results of beam simulation at beam line to RADEX experimental area and comparison with beam measurements are presented., Proceedings of the 25th Russian Particle Accelerator Conf., RuPAC2016, St. Petersburg, Russia

Wire-based beam instrumentation remains a reference for calibration of many other instruments, providing direct and accurate measurements with high resolution. However beam power increasing of existing and forthcoming ion linacs results in strict constraints on operation modes acceptable for control and diagnostics. Relevant simulations of wire thermal loads are necessary not only for a mode choice, but also for a preliminary design of such instrumentation. Simulations for different wire materials and various beam parameters are made. Features of the model are discussed. Numerical estimations and conclusions are presented in comparison with some experimental results., Proceedings of the 25th Russian Particle Accelerator Conf., RuPAC2016, St. Petersburg, Russia

Instruments for bunch shape and beam cross-section diagnostics at ion linacs are as important as complicated devices. Widespread Bunch Shape Monitors developed in INR RAS are used during a linac commissioning and optimization of beam dynamics. Beam Cross-Section Monitors implemented at INR RAS linac provide efficient non-destructive beam tuning and control. Features of both monitors investigated in simulations and beam tests are described. A variety of experimental results are presented., Proceedings of the 25th Russian Particle Accelerator Conf., RuPAC2016, St. Petersburg, Russia

Bunch shape monitors, based on secondary electrons emission, are widely used for measurements of longitudinal bunch profiles during a linac commissioning and initial optimization of beam dynamics. A typical phase resolution of these devices is about 1°. However it becomes insufficient for new modern linacs, which require a better resolution. Some developed methods for a phase resolution improvement are discussed., Proceedings of the 28th Linear Accelerator Conf., LINAC2016, East Lansing, MI, USA

Accelerated proton beam of INR linac is used for various facilities in multipurpose research complex of INR RAS, including experiments of neutron investigations and medical physics laboratories. In recent years beam instrumentation for transport channels of the complex has been upgraded and supplemented. Electrostatic pick-ups, beam current transformers, ionization chambers, multiwire SEM-grids, as well as its front-end and processing electronics were developed and combined to improve beam diagnostics. Some technical details and available results of beam measurements are presented in the paper., Proceedings of the 25th Russian Particle Accelerator Conf., RuPAC2016, St. Petersburg, Russia