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Alexander Kryukov

Publications and source records attributed to Alexander Kryukov.

At least 19 recordsLinked to original sources

Using a Conditional Generative Adversarial Network to Control the Statistical Characteristics of Generated Images for IACT Data Analysis

Generative adversarial networks are a promising tool for image generation in the astronomy domain. Of particular interest are conditional generative adversarial networks (cGANs), which allow you to divide images into several classes according to the value of some property of the image, and then specify the required class when generating new images. In the case of images from Imaging Atmospheric Cherenkov Telescopes (IACTs), an important property is the total brightness of all image pixels (image size), which is in direct correlation with the energy of primary particles. We used a cGAN technique to generate images similar to whose obtained in the TAIGA-IACT experiment. As a training set, we used a set of two-dimensional images generated using the TAIGA Monte Carlo simulation software. We artificiallly divided the training set into 10 classes, sorting images by size and defining the boundaries of the classes so that the same number of images fall into each class. These classes were used while training our network. The paper shows that for each class, the size distribution of the generated images is close to normal with the mean value located approximately in the middle of the corresponding class. We also show that for the generated images, the total image size distribution obtained by summing the distributions over all classes is close to the original distribution of the training set. The results obtained will be useful for more accurate generation of realistic synthetic images similar to the ones taken by IACTs.

astro-ph.IM

Application of convolutional neural networks for data analysis in TAIGA-HiSCORE experiment

The TAIGA experimental complex is a hybrid observatory for high-energy gamma-ray astronomy in the range from 10 TeV to several EeV. The complex consists of such installations as TAIGA- IACT, TAIGA-HiSCORE and a number of others. The TAIGA-HiSCORE facility is a set of wide-angle synchronized stations that detect Cherenkov radiation scattered over a large area. TAIGA-HiSCORE data provides an opportunity to reconstruct shower characteristics, such as shower energy, direction of arrival, and axis coordinates. The main idea of the work is to apply convolutional neural networks to analyze HiSCORE events, considering them as images. The distribution of registration times and amplitudes of events recorded by HiSCORE stations is used as input data. The paper presents the results of using convolutional neural networks to determine the characteristics of air showers. It is shown that even a simple model of convolutional neural network provides the accuracy of recovering EAS parameters comparable to the traditional method. Preliminary results of air shower parameters reconstruction obtained in a real experiment and their comparison with the results of traditional analysis are presented.

astro-ph.IM

Using conditional variational autoencoders to generate images from atmospheric Cherenkov telescopes

High-energy particles hitting the upper atmosphere of the Earth produce extensive air showers that can be detected from the ground level using imaging atmospheric Cherenkov telescopes. The images recorded by Cherenkov telescopes can be analyzed to separate gamma-ray events from the background hadron events. Many of the methods of analysis require simulation of massive amounts of events and the corresponding images by the Monte Carlo method. However, Monte Carlo simulation is computationally expensive. The data simulated by the Monte Carlo method can be augmented by images generated using faster machine learning methods such as generative adversarial networks or conditional variational autoencoders. We use a conditional variational autoencoder to generate images of gamma events from a Cherenkov telescope of the TAIGA experiment. The variational autoencoder is trained on a set of Monte Carlo events with the image size, or the sum of the amplitudes of the pixels, used as the conditional parameter. We used the trained variational autoencoder to generate new images with the same distribution of the conditional parameter as the size distribution of the Monte Carlo-simulated images of gamma events. The generated images are similar to the Monte Carlo images: a classifier neural network trained on gamma and proton events assigns them the average gamma score 0.984, with less than 3% of the events being assigned the gamma score below 0.999. At the same time, the sizes of the generated images do not match the conditional parameter used in their generation, with the average error 0.33.

astro-ph.IM

Interrelation of equivariant Gaussian processes and convolutional neural networks

Currently there exists rather promising new trend in machine leaning (ML) based on the relationship between neural networks (NN) and Gaussian processes (GP), including many related subtopics, e.g., signal propagation in NNs, theoretical derivation of learning curve for NNs, QFT methods in ML, etc. An important feature of convolutional neural networks (CNN) is their equivariance (consistency) with respect to the symmetry transformations of the input data. In this work we establish a relationship between the many-channel limit for CNNs equivariant with respect to two-dimensional Euclidean group with vector-valued neuron activations and the corresponding independently introduced equivariant Gaussian processes (GP).

cs.LG

Processing Images from Multiple IACTs in the TAIGA Experiment with Convolutional Neural Networks

Extensive air showers created by high-energy particles interacting with the Earth atmosphere can be detected using imaging atmospheric Cherenkov telescopes (IACTs). The IACT images can be analyzed to distinguish between the events caused by gamma rays and by hadrons and to infer the parameters of the event such as the energy of the primary particle. We use convolutional neural networks (CNNs) to analyze Monte Carlo-simulated images from the telescopes of the TAIGA experiment. The analysis includes selection of the images corresponding to the showers caused by gamma rays and estimating the energy of the gamma rays. We compare performance of the CNNs using images from a single telescope and the CNNs using images from two telescopes as inputs.

astro-ph.IM

Complete Decentralization of Distributed Data Storages Based on Blockchain Technology

The work presents a solution for completely decentralized data management systems in geographically distributed environments with administratively unrelated or loosely related user groups and in conditions of partial or complete lack of trust between them. The solution is based on the integration of blockchain technology, smart contracts and provenance metadata driven data management. Architecture, operation principles and algorithms developed provides fault-tolerant, safe and reliable management of provenance metadata, control of operations with data files, as well as resource access management in collaborative distributed computing systems. The latter refer to distributed systems formed by combining into a single pool of computer resources of various organizations (institutions) to work together in the framework of some project.

cs.DC

Analysis of the HiSCORE Simulated Events in TAIGA Experiment Using Convolutional Neural Networks

TAIGA is a hybrid observatory for gamma-ray astronomy at high energies in range from 10 TeV to several EeV. It consists of instruments such as TAIGA-IACT, TAIGA-HiSCORE, and others. TAIGA-HiSCORE, in particular, is an array of wide-angle timing Cherenkov light stations. TAIGA-HiSCORE data enable to reconstruct air shower characteristics, such as air shower energy, arrival direction, and axis coordinates. In this report, we propose to consider the use of convolution neural networks in task of air shower characteristics determination. We use Convolutional Neural Networks (CNN) to analyze HiSCORE events, treating them like images. For this, the times and amplitudes of events recorded at HiSCORE stations are used. The work discusses a simple convolutional neural network and its training. In addition, we present some preliminary results on the determination of the parameters of air showers such as the direction and position of the shower axis and the energy of the primary particle and compare them with the results obtained by the traditional method.

astro-ph.IM

Towards the Baikal Open Laboratory in Astroparticle Physics

The open science framework defined in the German-Russian Astroparticle Data Life Cycle Initiative (GRADLCI) has triggered educational and outreach activities at the Irkutsk State University (ISU), which is actively participated in the two major astroparticle facilities in the region: TAIGA observatory and Baikal-GVD neutrino telescope. We describe the ideas grew out of this unique environment and propose a new open science laboratory based on education and outreach as well as on the development and testing new methods and techniques for the multimessenger astronomy.

astro-ph.IM

AstroDS -- A Distributed Storage for Astrophysics of Cosmic Rays. Current Status

Currently, the processing of scientific data in astroparticle physics is based on various distributed technologies, the most common of which are Grid and cloud computing. The most frequently discussed approaches are focused on large and even very large scientific experiments, such as Cherenkov Telescope Array. We, by contrast, offer a solution designed for small to medium experiments such as TAIGA. In such experiments, as a rule, historically developed specific data processing methods and specialized software are used. We have specifically designed a distributed (cloud) data storage for astroparticle physics data collaboration in medium-sized experiments. In this article, we discuss the current state of our work using the example of the TAIGA and CASCADE experiments. A feature of our approach is that we provide our users with scientific data in the form to which they are accustomed to in everyday work on local resources.

astro-ph.IM

The Current Design and Implementation of the AstroDS Data Aggregation Service

AstroDS is a distributed storage for Cosmic Ray Astrophysics. The primary goal of Astro DS is to gather data measured by the instruments of various physical experiments such as TAIGA, TUNKA, KASCADE into global storage and provide the users with a standardized user-friendly interface to search for the datasets that match certain conditions. AstroDS consists of a set of distributed microservices components that communicate with each other through the Internet via REST API. The core component of AstroDS is the Data Aggregation Service that orchestrates other components to provide access to data. The development process of AstroDS started in 2019. This paper describes the current design and implementation of the Data Aggregation Service and also the benefits it brings to the astrophysical community in the early state.

astro-ph.IM

Data Aggregation In The Astroparticle Physics Distributed Data Storage

German-Russian Astroparticle Data Life Cycle Initiative is an international project whose aim is to develop a distributed data storage system that aggregates data from the storage systems of different astroparticle experiments. The prototype of such a system, which is called the Astroparticle Physics Distributed Data Storage (APPDS), has been being developed. In this paper, the Data Aggregation Service, one of the core services of APDDS, is presented. The Data Aggregation Service connects all distributed services of APPDS together to find the necessary data and deliver them to users on demand.

astro-ph.IM

German-Russian Astroparticle Data Life Cycle Initiative

A data life cycle (DLC) is a high-level data processing pipeline that involves data acquisition, event reconstruction, data analysis, publication, archiving, and sharing. For astroparticle physics a DLC is particularly important due to the geographical and content diversity of the research field. A dedicated and experiment spanning analysis and data centre would ensure that multi-messenger analyses can be carried out using state-of-the-art methods. The German-Russian Astroparticle Data Life Cycle Initiative (GRADLCI) is a joint project of the KASCADE-Grande and TAIGA collaborations, aimed at developing a concept and creating a DLC prototype that takes into account the data processing features specific for the research field. An open science system based on the KASCADE Cosmic Ray Data Centre (KCDC), which is a web-based platform to provide the astroparticle physics data for the general public, must also include effective methods for distributed data storage algorithms and techniques to allow the community to perform simulations and analyses with sophisticated machine learning methods. The aim is to achieve more efficient analyses of the data collected in different, globally dispersed observatories, as well as a modern education to Big Data Scientist in the synergy between basic research and the information society. The contribution covers the status and future plans of the initiative.

astro-ph.IM

Deep Learning for Energy Estimation and Particle Identification in Gamma-ray Astronomy

Deep learning techniques, namely convolutional neural networks (CNN), have previously been adapted to select gamma-ray events in the TAIGA experiment, having achieved a good quality of selection as compared with the conventional Hillas approach. Another important task for the TAIGA data analysis was also solved with CNN: gamma-ray energy estimation showed some improvement in comparison with the conventional method based on the Hillas analysis. Furthermore, our software was completely redeveloped for the graphics processing unit (GPU), which led to significantly faster calculations in both of these tasks. All the results have been obtained with the simulated data of TAIGA Monte Carlo software; their experimental confirmation is envisaged for the near future.

astro-ph.IM

Distributed data storage for modern astroparticle physics experiments

The German-Russian Astroparticle Data Life Cycle Initiative is an international project launched in 2018. The Initiative aims to develop technologies that provide a unified approach to data management, as well as to demonstrate their applicability on the example of two large astrophysical experiments - KASCADE and TAIGA. One of the key points of the project is the development of a distributed storage, which, on the one hand, will allow data of several experiments to be combined into a single repository with unified interface, and on the other hand, will provide data to all participants of experimental groups for multi-messenger analysis. Our approach to storage design is based on the single write-multiple read (SWMR) model for accessing raw or centrally processed data for further analysis. The main feature of the distributed storage is the ability to extract data either as a collection of files or as aggregated events from different sources. In the last case the storage provides users with a special service that aggregates data from different storages into a single sample. Thanks to this feature, multi-messenger methods used for more sophisticated data exploration can be applied. Users can use both Web-interface and Application Programming Interface (API) for accessing the storage. In this paper we describe the architecture of a distributed data storage for astroparticle physics and discuss the current status of our work.

cs.DC

A distributed data warehouse system for astroparticle physics

A distributed data warehouse system is one of the actual issues in the field of astroparticle physics. Famous experiments, such as TAIGA, KASCADE-Grande, produce tens of terabytes of data measured by their instruments. It is critical to have a smart data warehouse system on-site to store the collected data for further distribution effectively. It is also vital to provide scientists with a handy and user-friendly interface to access the collected data with proper permissions not only on-site but also online. The latter case is handy when scientists need to combine data from different experiments for analysis. In this work, we describe an approach to implementing a distributed data warehouse system that allows scientists to acquire just the necessary data from different experiments via the Internet on demand. The implementation is based on CernVM-FS with additional components developed by us to search through the whole available data sets and deliver their subsets to users' computers.

astro-ph.IM

A framework to monitor activities of satellite data processing in real-time

Space Monitoring Data Center (SMDC) of SINP MSU is one of the several centers in the world that collects data on the radiational conditions in near-Earth orbit from various Russian (Lomonosov, Electro-L1, Electro-L2, Meteor-M1, Meteor-M2, etc.) and foreign (GOES 13, GOES 15, ACE, SDO, etc.) satellites. The primary purposes of SMDC are: aggregating heterogeneous data from different sources; providing a unified interface for data retrieval, visualization, analysis, as well as development and testing new space weather models; and controlling the correctness and completeness of data. Space weather models rely on data provided by SMDC to produce forecasts. Therefore, monitoring the whole data processing cycle is crucial for further success in the modelling of physical processes in near-Earth orbit based on the collected data. To solve the problem described above, we have developed a framework called Live Monitor at SMDC. Live Monitor allows watching all stages and program components involved in each data processing cycle. All activities of each stage are logged by Live Monitor and shown in real-time on a web interface. When an error occurs, a notification message will be sent to satellite operators via email and the Telegram messenger service so that they could take measures in time. The Live Monitor's API can be used to create a customized monitoring service with minimum coding.

astro-ph.IM

Application of HUBzero platform for the educational process in astroparticle physics

In the frame of the Karlsruhe-Russian Astroparticle Data Life Cycle Initiative it was proposed to deploy an educational resource astroparticle.online for the training of students in the field of astroparticle physics. This resource is based on HUBzero, which is an open-source software platform for building powerful websites, which supports scientific discovery, learning, and collaboration. HUBzero has been deployed on the servers of Matrosov Institute for System Dynamics and Control Theory. The educational resource astroparticle.online is being filled with the information covering cosmic messengers, astroparticle physics experiments and educational courses and schools on astroparticle physics. Furthermore, the educational resource astroparticle.online can be used for online collaboration. We present the current status of this project and our first experience of application of this service as a collaboration framework.

astro-ph.IM

The Approach to Managing Provenance Metadata and Data Access Rights in Distributed Storage Using the Hyperledger Blockchain Platform

The paper suggests a new approach based on blockchain technologies and smart contracts to creation of a distributed system for managing provenance metadata, as well as access rights to data in distributed storages, which is fault-tolerant, safe and secure from the point of view of preservation of metadata records from accidental or intentional distortions. The implementation of the proposed approach is based on the permissioned blockchains and on the Hyperledger Fabric blockchain platform in conjunction with Hyperledger Composer.

cs.DC