FLNP SEMINAR, June 17, 2021 (Thursday) at 11:00, online

"A source of ultracold neutrons slowed down by a magnetic or material UCN trap"

V.V.Nesvizhevsky (Nuclear & Particle Physics Department, ILL, Grenoble, France)

Ultracold neutrons (UCNs) are widely used in the physics of elementary particles and fundamental interactions, and can potentially be used in neutron scattering. However, most of these studies are limited by the available UCN densities and fluxes. One of the ways to increase them, as noted already in the first years of research with UCN, is to use peak fluxes in pulsed neutron sources, orders of magnitude higher than the average. In the present work, the concept of UCN sources is proposed, which makes it possible to implement this idea. We propose to produce very cold neutrons (VCN) in converters located in neutron sources and extract them with low losses. We propose a new way of focusing them in time, as well as their deceleration to UCN energies by an escaping decelerating material or magnetic trap. For both pulsed and permanent neutron sources, this method can provide high conversion efficiency of VCN to UCN.

DSC FLNP SEMINAR, June 18 (Friday), 11:00, online

"Algorithms and programs for express-analysis of data in List-Mode of neutron scattering, measured on 2-axis PSDs with a delay line using data acquisition systems based on CAEN digitizers"

Litvinenko E.I.

When using CAEN digitizers, serving as electronics of general use, in the considered case of 2-axis PSDs with a delay line, the task of constructing neutron events from measured data should be performed at the software level. The statement of problem and the developed software for a sufficiently fast transformation of the measured data into formats that allow obtaining and visualizing the positional and time-of-flight spectra of neutrons in the process or immediately after the end of the current measurement are described in the paper.

Joint Seminar of the DSC IBR-2 and the DNICM, June 15, 2021 (Thuesday) at 15:00, online

"Interference of waves: from neutron interferometry to neutron spin-echo"

A.I.Ioffe  (based on the doctoral dissertation)

Joint JINR Seminar, June 9, 2021 (Wednesday), 10:00, at the Conference Hall of Bogoliubov Laboratory of Theoretical Physics JINR and online

"Quantum Computing Using Multilevel Systems"

Aleksey Fedorov (Head of the group of Quantum Information Technologies, "Skolkovo")

Quantum computers are computing devices that use quantum phenomena (such as quantum superposition and quantum entanglement) to solve problems. Quantum computing devices have the potential to outperform classical computers in a variety of tasks, such as cryptanalysis, complex system modeling, and machine learning. The presentation will provide an overview of various models of quantum computing, as well as the main applications of quantum computing devices. We will also consider a model of quantum computing using multilevel systems (qudits). The proposed model is based on a combination of several approaches. The first approach exploits the general relationship between the dimension of the qubits and their link topology, which is necessary for a scalable multi-qudit processor, where higher levels of qudits are used to replace auxiliary qubits. The second approach uses the decomposition of multi-level systems into a set of two-level systems. The application of the approach in current experiments with quantum information processing systems is discussed. The questions of the analysis of quantum computing devices in the context of the theory of open quantum systems will also be touched upon.

DNP Seminar, June 2 (Wednesday), 11:00, online

 "Insights into the Archaeometric Studies of Artifacts with Emphasis on the Icon Painting"

Mina Magdy (senior scientist at the National Museum of Egyptian Civilization NMEC)

The preservation of cultural heritage is an interdisciplinary collaboration of different sciences. The complementation of various analytical techniques can provide a wealth of information that is useful for a better understanding of the chemical patterns of different materials; it could be used to explore the bulk or surface, to observe the microscopic or macroscopic features, to determine the chemical or physical properties, and to reach the different detection limits of the profiling layers. The output of the characterization process is the decision-making of the preservation strategy, and the outcome is the valorization of the cultural heritage artworks. The archaeological materials change with time, so the preservation procedures are employed to safeguard the cultural heritage. The current research work concerns the aging phenomena of painting artworks.