The article discusses the design flow for complex functional VLSI circuits at the stage of synthesis and physical synthesis using foreign and domestic CAD systems, which makes it possible to ensure, on the one hand, the characteristics of the VLSI in accordance with the capabilities of foreign CAD systems, on the other hand, to exclude undeclared functions that are possible due to use of Western CAD systems. The design flow is divided into two main stages: logical synthesis and physical synthesis. Security is ensured by using only domestic trusted RTL codes and IP blocks and checking, carried out by domestic trusted CAD, for compliance of the source RTL code obtained as a result of design on foreign CAD with the netlist, as well as analysis for the absence of circuits and circuits not connected to inputs/outputs the developed scheme. In addition to domestic CAD, it is possible to use verified CAD based on the freely available YOSYS. The design flow should include four additional domestic ERC checks; the functions of these checks are given. The design flow is intended for the creation of complex functional VLSI by Russian design centers and Centers for collective design of radio-electronic products. The flow of synthesis and physical synthesis is considered, indicating the names of the files obtained at each stage. A table is presented of the CAD products used by Synopsys, Cadence, Mentor Graphics (Siemens) for carrying out the considered design stages with technological standards of 28-65 nm. In conclusion, a justification for the design flow for complex functional VLSI using Western and domestic CAD systems is given and the work necessary for the development of this direction is listed.

The problems of creating of high-performance embedded computing systems based on microprocessors KOMDIV is considered. Processor performance is dependent upon three characteristics: clock cycle, clock cycles per instruction, and instruction count. These characteristics for microprocessors KOMDIV are optimized using parameter performance/power consumption and requirements of embedded systems.

Space radiation interacting with electronic components of on-board computing or navigation unit can bring to it's malfunction. Using error tolerant electronic components is a key factor ensuring safety of Space missions. The Muller C-element is one of the main part of the asynchronous circuits and also can be found in synchronous ones. Being sequential by its nature, it is vulnerable to single event upsets. We propose three CMOS circuit implementations of a soft error tolerant Muller C-element, whose tolerance is achieved by using of the well-known DICE-principle and is proved by SPICE simulations.

Extraterrestrial gamma-ray astronomy is now a source of new knowledge in the fields of astrophysics, cosmic-ray physics, and the nature of dark matter. The next absolutely necessary step in the development of extraterrestrial high-energy gamma-ray astronomy is the improvement of the physical and technical characteristics of gamma-ray telescopes, especially the angular and energy resolutions. Such a new generation telescope will be GAMMA-400. GAMMA-400, currently developing gamma-ray telescope, together with X-ray telescope will precisely and detailed observe in the energy range of ~20 MeV to ~1000 GeV and 3-30 keV the Galactic plane, especially, Galactic Center, Fermi Bubbles, Crab, Cygnus, etc. The GAMMA- 400 will operate in the highly elliptic orbit continuously for a long time with the unprecedented angular (~0.01{\deg} at E{\gamma} = 100 GeV) and energy (~1% at E{\gamma} = 100 GeV) resolutions better than the Fermi-LAT, as well as ground gamma-ray telescopes, by a factor of 5-10. GAMMA-400 will permit to resolve gamma rays from annihilation or decay of dark matter particles, identify many discrete sources (many of which are variable), to clarify the structure of extended sources, to specify the data on the diffuse emission.

Fermi-LAT has made a significant contribution to the study of high-energy gamma-ray diffuse emission and the observations of 3000 discrete sources. However, one third of all gamma-ray sources (both galactic and extragalactic) are unidentified, the data on the diffuse gamma-ray emission should be clarified, and signatures of dark matter particles in the high-energy gamma-ray range are not observed up to now. GAMMA-400, the currently developing gamma-ray telescope, will have angular (∼0.01∘ at 100 GeV) and energy (∼1% at 100 GeV) resolutions in the energy range of 10–1000 GeV which are better than Fermi-LAT (as well as ground gamma-ray telescopes) by a factor of 5–10. It will observe some regions of the Universe (such as the Galactic Center, Fermi Bubbles, Crab, Cygnus, etc.) in a highly elliptic orbit (without shading the telescope by the Earth) continuously for a long time. It will allow us to identify many discrete sources, to clarify the structure of extended sources, to specify the data on the diffuse emission, and to resolve gamma rays from dark matter particles.

The future GAMMA-400 space mission is aimed for the study of gamma rays in the energy range from ~20 MeV up to 1 TeV. The observations will carry out with GAMMA-400 gamma-ray telescope installed on-board the Russian Space Observatory. We present the detailed description of the architecture and performances of scientific data acquisition system (SDAQ) developing by SRISA for the GAMMA-400 instrument. SDAQ provides the collection of the data from telescope detector subsystems (up to 100 GB per day), the preliminary processing of scientific information and its accumulation in mass memory, transferring the information from mass memory to the satellite high-speed radio line for its transmission to the ground station, the control and monitoring of the telescope subsystems. SDAQ includes special space qualified chipset designed by SRISA and has scalable modular net structure based on fast and high-reliable serial interfaces.

Single Event Transient (SET) is a current and voltage disturbance in an integrated circuit (IC), caused by charged particle impact. In modern IC technologies single charged particle can cause multiple SETs on multiple electrical nodes, this can lead to faults. There are several mitigation techniques with their drawbacks affecting circuit performance. This work presents a comparison of experimental data with simulation results acquired by the means of our technique and tools. Our technique is able to simulate sub-100 nm IC performance under multiple SET using industry standard SPICE simulator, without incorporation of a T-CAD or physical measurements, and taking into account layout of the device.

The present status of scientific data acquisition system (SDAQ) developed by SRISA for the GAMMA -400 space gamma-ray telescope mission is presented. SDAQ provides the collection of the data from telescope detector subsystems (up to 100 GB per day), the preliminary processing of scientific information and its accumulation in mass memory, transferring the information from mass memory to the satellite radio line for its transmission to the ground station, the control and monitoring of the telescope subsystems. SDAQ includes special space qualified chipset designed by SRISA and has scalable modular net structure based on fast and high-reliable SerialRapidlO 1.25 Gbit/s interface.

The GAMMA-400 gamma-ray telescope with excellent angular and energy resolutions is designed to search for signatures of dark matter in the fluxes of gamma-ray emission and electrons + positrons. Precision investigations of gamma-ray emission from Galactic Center, Crab, Vela, Cygnus, Geminga, and other regions will be performed, as well as diffuse gamma-ray emission, along with measurements of high-energy electron + positron and nuclei fluxes. Furthermore, it will study gamma-ray bursts and gamma-ray emission from the Sun during periods of solar activity. The energy range of GAMMA-400 is expected to be from ~20 MeV up to TeV energies for gamma rays, up to 20 TeV for electrons + positrons, and up to 10E15 eV for cosmic-ray nuclei. For high-energy gamma rays with energy from 10 to 100 GeV, the GAMMA-400 angular resolution improves from 0.1{\deg} to ~0.01{\deg} and energy resolution from 3% to ~1%; the proton rejection factor is ~5x10E5. GAMMA-400 will be installed onboard the Russian space observatory.

The description of scientific data acquisition system (SDAS) designed by SRISA for the GAMMA-400 space project is presented. We consider the problem of different level electronics unification: the set of reliable fault-tolerant integrated circuits fabricated on Silicon-on-Insulator 0.25 mkm CMOS technology and the high-speed interfaces and reliable modules used in the space instruments. The characteristics of reliable fault-tolerant very large scale integration (VLSI) technology designed by SRISA for the developing of computation systems for space applications are considered. The scalable net structure of SDAS based on Serial RapidIO interface including real-time operating system BAGET is described too.

Muller C-element is one of the main parts of an asynchronous circuit. Being sequential by its nature, it is vulnerable to single event upsets (SEU). We propose three 65 nm CMOS circuit implementations of SEU tolerant C-element, whose tolerance is achieved by using of well-known DICE principle and is proved by SPICE simulations and semi-empirical estimations.

Fermi-LAT has made a significant contribution to the study of high-energy gammaray diffuse emission and the observation of ~3000 discrete sources. However, one third of all gamma-ray sources (both galactic and extragalactic) are unidentified, the data on the diffuse gamma-ray emission should be clarified, and signatures of dark matter particles in the high energy gamma-ray range are not observed up to now. GAMMA-400, currently developing gamma-ray telescope, will have the angular (~0.01° at 100 GeV) and energy (~1% at 100 GeV) resolutions in the energy range of 10-1000 GeV better than the Fermi-LAT (as well as ground gamma-ray telescopes) by a factor of 5-10 and observe some regions of the Universe (such as Galactic Center, Fermi Bubbles, Crab, Cygnus, etc.) in the highly elliptic orbit (without shading the telescope by the Earth) continuously for a long time. It will permit to identify many discrete sources, to clarify the structure of extended sources, to specify the data on the diffuse emission, and to resolve gamma rays from dark matter particles. 1 International Conference on Particle Physics and Astrophysics IOP Publishing IOP Conf. Series: Journal of Physics: Conf. Series 798 (2017) 012011 doi:10.1088/1742-6596/798/1/012011 International Conference on Recent Trends in Physics 2016 (ICRTP2016) IOP Publishing Journal of Physics: Conference Series 755 (2016) 011001 doi:10.1088/1742-6596/755/1/011001 Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd 1. Current gamma-ray study challenges 1.1. Analysis of the Fermi-LAT and ground-based telescope gamma-ray results Since 2008 Fermi-LAT is operating in a near-Earth orbit in the scanning mode and surveying full sky every three hours. Up to now, three catalogs of gamma-ray sources have been published based on the Fermi-LAT observational results: 1FGL [1] and 2FGL [2] for the energy range of 0.1-100 GeV, 3FGL [3] for the energy range of 0.1-300 GeV. Moreover two catalogs of high-energy gamma-ray sources were published: 1FHL [4] for the energy above 10 GeV and 2FHL [5] for the energy range of 50-2000 GeV. From these catalogs, it is seen that 33% of gamma-ray sources are unidentified. The exposition of the source observations presented in [3] shows that during four years of the operation Fermi-LAT observed, e.g., the Galactic center during only ~12% or 1/8 of total operation time. Based on results of gamma-ray observations at energies above 100 GeV by ground-based facilities VERITAS [6], MAGIC [7], H.E.S.S. [8] and others the TeVCat catalog of discrete gamma-ray sources [9] was created, which contains about 180 sources and mainly matches with 3FGL. It is important to note that the observational data from Fermi-LAT and ground-based facilities were obtained for the energy ranges, which overlap insufficiently for many gamma-ray sources. Sometimes they don't overlap at all. Hence, the frontier range around 100 GeV is still very interesting for investigations from space. In addition, the angular resolution of Fermi-LAT, existing ground-based telescopes, and even planned CTA [10] in the region of around 10-300 GeV is only ~0.1°. Therefore a much better angular resolution is required in order to identify many gamma-ray sources. 1.2. Indirect searches of dark matter Another very interesting and important goal in the studies of gamma-ray sky is indirect searches of dark matter (DM). In general, an exact physical nature of DM is a top puzzle in the modern astrophysics. There are many candidates on the DM role being proposed. However, WIMPs with mass between several GeV and several TeV are still considered as the most probable candidate [11]. WIMPs can annihilate or decay with the production of gamma rays. This emission can have both continuum energy spectrum or monoenergetic lines. This depends on which annihilation channel realizes in the nature. The continuum spectrum would come in the case of annihilation into particle pairs like or others and gamma-ray lines would be produced in the case of direct annihilation into photons χχ  γγ, γZ, γH [12]). Figure 1. Expected energy spectrum for the annihilation of 300-GeV WIMP producing gamma rays (γγ, γZ, and γH lines), which can be resolved from background by various telescopes with the energy resolutions of 10%, 5%, and 0.5% [13]. 2 International Conference on Particle Physics and Astrophysics IOP Publishing IOP Conf. Series: Journal of Physics: Conf. Series 798 (2017) 012011 doi:10.1088/1742-6596/798/1/012011

A description of the control and data transfer management system for scientific instrumentation involved in the GAMMA-400 space project is given. The technical capabilities of all specialized equipment to provide the functioning of the scientific instrumentation and satellite support systems are unified in a single structure. Control of the scientific instruments is maintained using one-time pulse radio commands, as well as program commands in the form of 16-bit code words, which are transmitted via onboard control system and scientific data acquisition system. Up to 100 GByte of data per day can be transferred to the ground segment of the project. The correctness of the proposed and implemented structure, engineering solutions and electronic elemental base selection has been verified by the experimental working-off of the prototype of the GAMMA-400 scientific complex in laboratory conditions.

The main goal for the GAMMA-400 gamma-ray telescope mission is to perform a sensitive search for signatures of dark matter particles in high-energy gamma-ray emission. Measurements will also concern the following scientific goals: detailed study of the Galactic center region, investigation of point and extended gamma-ray sources, studies of the energy spectra of Galactic and extragalactic diffuse emissions. To perform these measurements the GAMMA-400 gamma-ray telescope possesses unique physical characteristics for energy range from ~20 MeV to ~1000 GeV in comparison with previous and current space and ground-based experiments. The major advantage of the GAMMA-400 instrument is excellent angular and energy resolutions for gamma-rays above 10 GeV. The gamma-ray telescope angular and energy resolutions for the main aperture at 100-GeV gamma rays are ~0.01 deg and ~1%, respectively. The special goal is to improve physical characteristics in the low- energy range from ~20 MeV to 100 MeV. Minimizing the amount of dead matter in the telescope aperture allows us to obtain the angular and energy resolutions better in this range than in current space missions. The gamma-ray telescope angular resolution at 50-MeV gamma rays is better than 5 deg and energy resolution is ~10%. We report the method providing these results.

The GAMMA-400 gamma-ray telescope is intended to measure the fluxes of gamma-rays and cosmic-ray electrons and positrons in the energy range from 100 MeV to several TeV. Such measurements concern the following scientific tasks: investigation of point sources of gamma-rays, studies of the energy spectra of Galactic and extragalactic diffuse emission, studies of gamma-ray bursts and gamma-ray emission from the Sun, as well as high precision measurements of spectra of high-energy electrons and positrons. Also the GAMMA- 400 instrument provides the possibility for protons and nuclei measurements up to knee. But the main goal for the GAMMA-400 mission is to perform a sensitive search for signatures of dark matter particles in high-energy gamma-ray emission. To fulfill these measurements the GAMMA-400 gamma-ray telescope possesses unique physical characteristics in comparison with previous and present experiments. The major advantage of the GAMMA-400 instrument is excellent angular and energy resolution for gamma-rays above 10 GeV. The GAMMA-400 experiment will be installed onboard of the Navigator space platform, manufactured by the NPO Lavochkin Association. The expected orbit will be a highly elliptical orbit (with apogee 300.000 km and perigee 500 km) with 7 days orbital period. An important profit of such an orbit is the fact that the full sky coverage will always be available for gamma ray astronomy.

Single Event Transient (SET) caused by charged particle traveling through the sensitive volume of integral circuit (IC) may lead to different errors in digital circuits in some cases. In technologies below 180 nm, a single particle can affect multiple devices causing multiple SET. This fact adds the complexity to fault tolerant devices design, because the schematic design techniques become useless without their layout consideration. The most common layout mitigation technique is a spatial separation of sensitive nodes of hardened circuits. Spatial separation decreases the circuit performance and increases power consumption. Spacing should thus be reasonable and its scaling follows the device dimensions’ scaling trend. This paper presents the development of the SET simulation approach comprised of SPICE simulation with “double exponent” current source as SET model. The technique uses layout in GDSII format to locate nearby devices that can be affected by a single particle and that can share the generated charge. The developed software tool automatizes multiple simulations and gathers the produced data to present it as the sensitivity map. The examples of conducted simulations of fault tolerant cells and their sensitivity maps are presented in this paper.

The development of the GAMMA-400 γ-ray telescope continues. The GAMMA-400 is designed to measure fluxes of γ-rays and the electron-positron cosmic-ray component possibly associated with annihilation or decay of dark matter particles; and to search for and study in detail discrete γ-ray sources, to measure the energy spectra of Galactic and extragalactic diffuse γ-rays, and to study γ-ray bursts and γ-rays from the active Sun. The energy range for measuring γ-rays and electrons (positrons) is from 100 MeV to 3000 GeV. For 100-GeV γ-rays, the γ-ray telescope has an angular resolution of ∼0.01°, an energy resolution of ∼1%, and a proton rejection factor of ∼5 × 105. The GAMMA-400 will be installed onboard the Russian Space Observatory.

GAMMA-400 γ-ray telescope is designed to measure fluxes of γ-rays and the electron–positron cosmic ray component possibly generated in annihilation or decay of dark matter particles; to search for and study in detail discrete γ-ray sources, to examine the energy spectra of Galactic and extragalactic diffuse γ-rays, to study γ-ray bursts and γ-rays from the active Sun. GAMMA-400 consists of plastic scintillation anticoincidence top and lateral detectors, converter-tracker, plastic scintillation detectors for the time-of-flight system (TOF), two-part calorimeter (CC1 and CC2), plastic scintillation lateral detectors of calorimeter, plastic scintillation detectors of calorimeter, and neutron detector. The converter-tracker consists of 13 layers of double (x, y) silicon strip coordinate detectors (pitch of 0.08 mm). The first three and final one layers are without tungsten while the middle nine layers are interleaved with nine tungsten conversion foils. The thickness of CC1 and CC2 is 2 X0 (0.1λ0) and 23 X0 (1.1λ0) respectively (where X0 is radiation length and λ0 is nuclear interaction one). The total calorimeter thickness is 25 X0 or 1.2λ0 for vertical incident particles registration and 54 X0 or 2.5λ0 for laterally incident ones. The energy range for γ-rays and electrons (positrons) registration in the main aperture is from ∼0.1 GeV to ∼3.0 TeV. The γ-ray telescope main aperture angular and energy resolutions are respectively ∼0.01 and ∼1% for 102 GeV γ-quanta, the proton rejection factor is ∼5×105. The first three strip layers without tungsten provide the registration of γ-rays down to ∼20 MeV in the main aperture. Also this aperture allows investigating high energy light nuclei fluxes characteristics. Electrons, positrons, light nuclei and gamma-quanta will also register from the lateral directions due to special aperture configuration. Lateral aperture energy resolution is the same as for main aperture for electrons, positrons, light nuclei and gamma-quanta in energy range E>1.0 GeV. But using lateral aperture it is possible to detect low-energy gammas in the ranges 0.2 − 10 MeV and 10 MeV – 1.0 GeV with energy resolution 8% − 2% and 2% correspondingly accordingly to GAMMA-400 “Technical Project” stage results. Angular resolution in the lateral aperture provides only for low-energy gamma-quanta from non-stationary events (GRB, solar flares and so on) due segments of CC2 count rate analysis. GAMMA-400 γ-ray telescope will be installed onboard the Russian Space Observatory GAMMA-400. The lifetime of the space observatory will be at least seven years. The launch of the space observatory is scheduled for the early 2020s.

GAMMA-400 is a new space mission, designed as a dual experiment, capable to study both high energy gamma rays (from $\sim$100 MeV to few TeV) and cosmic rays (electrons up to 20 TeV and nuclei up to $\sim$10$^{15}$ eV). The full simulation framework of GAMMA-400 is based on the Geant4 toolkit. The details of the gamma-ray reconstruction pipeline in the pre-shower and calorimeter will be outlined. The performance of GAMMA-400 (PSF, effective area) have been obtained using this framework. The most updated results on them will be shown.

GAMMA-400 is a new space mission, designed as a dual experiment, capable to study both high energy gamma rays (from $\sim$100 MeV to few TeV) and cosmic rays (electrons up to 20 TeV and nuclei up to $\sim$10$^{15}$ eV). The full simulation framework of GAMMA-400 is based on the Geant4 toolkit. The details of the gamma-ray reconstruction pipeline in the three main instruments (Tracker, Imaging Calorimeter, Homogeneous Calorimeter) will be outlined. The performance of GAMMA-400 (PSF, effective area and sensitivity) have been obtained using this framework. The most updated results on them will be shown.