Physics of Particles and Nuclei Letters最新文献

A deep neural network with long-short-term memory and permutation-invariant feature encoder is proposed for distinguishing electrons, photons, muons, pions, and protons in the novel detector SuperFGD. SuperFGD is a highly granular scintillator target that is a central component of the upgraded ND280 near detector in the T2K neutrino experiment. Precise particle identification is essential for reconstructing neutrino interactions and reducing systematic uncertainties in T2K’s oscillation measurements. The proposed model demonstrates robust discrimination performance across a range of particle types.

Non-destructive neutron radiography and tomography were applied to investigate the internal structure of a ceramic vessel lid originating from the medieval settlement of Otrar (Turkestan region, Kazakhstan). Tomographic reconstruction confirmed the presence of a freely movable spherical element located inside the lid. Quantitative analysis of the reconstructed three-dimensional volume allowed determination of the sphere’s geometrical parameters, with a calculated volume of 1.12(3) mm³ and a diameter of 1.29(1) mm. Neutron attenuation profiles show identical characteristics for the lid and the internal sphere, implying the same ceramic material.

In this work, We investigate the decay of fission isomers formed in spontaneous fission of ²⁵²Cf. In the framework of TNS model, we describe the formation of the TNS and its decay, with subsequent formation of fission isomer as a dinuclear system. The modification of DNS half-lives we calculate using a quantum-mechanical tunneling approach. Our calculations reveal a dramatic catalytic effect of the external Coulomb field on the decay process of DNS. Our results provide a direct and quantitative explanation for the experimental observations reported by [1]. This work bridges the gap between theoretical predictions and experimental observations, providing a comprehensive understanding of this fascinating nuclear decay phenomenon.

In this work, a technique for obtaining constraints on the (Z{kern 1pt} ')-boson mass is developed for the scenario of “ideal” agreement of the expected data with the Standard Model at future ({{e}^{ + }}{{e}^{ - }}) colliders. The methodology has been tested using statistical data simulation from the process ({{e}^{ + }}{{e}^{ - }} to {{mu }^{ + }}{{mu }^{ - }}) at the ILC with 1 TeV center-of-mass energy and an integrated luminosity of 8 ab^–1 using unpolarized electron and positron beams. The correctness of the data simulation is confirmed by comparing the obtained constraints with asymptotic ones. As a result of testing the methodology, quantitative estimates of the (Z{kern 1pt} ')-boson mass have been obtained for a wide range of models within the framework of which its existence is predicted. The presented data simulation scheme and the technique for obtaining constraints are the basis for subsequent accounting for systematics and analysis of the polarization observables.

Anisotropic flow and global polarization are the key observables for characterizing properties of strongly-interacting matter in relativistic heavy-ion collisions at NICA energies ((sqrt {{{s}_{{NN}}}} ) = 2.5–11 GeV). A significant challenge for the MPD experiment is achieving the necessary statistical precision for these measurements, particularly for direct photons, ϕ-mesons, (Sigma ) and Λ hyperons. To address this issue, we have developed a statistical event resampling afterburner package. This tool was validated using simulated Xe + Xe collisions at (sqrt {{{s}_{{NN}}}} ) = 2.87 GeV generated with the UrQMD model. The application of this afterburner package resulted in a substantial enhancement of the resolution of the directed (({{v}_{1}})) and elliptic (({{v}_{2}})) flow of Λ hyperons, in addition to their global polarization. This work confirms the method’s utility for the future feasibility studies and data analysis in the MPD experiment.

We study hydrodynamic effects of bulk properties of the matter produced in Au + Au collisions at (sqrt {{{s}_{{NN}}}} = 7.7) GeV measuring production of the following particles ({{pi }^{ pm }}), ({{K}^{ pm }}), p and (bar {p}) with AMPT, EPOS4, SMASH, and PYTHIA8 Monte Carlo models. Mid-rapidity ((left| y right| < 0.1)) analysis of the transverse momentum spectra, antiparticle-to-particle and mixed-particles ratios, in dependence of various collision centralities are presented and compared with the 2010 data collected by STAR experiment in the Beam Energy Scan (BES) program at the Relativistic Heavy Ion Collider (RHIC).

Big modern physics experiments represent a collaboration of workgroups and require wide variety of different electronic equipment. Besides trigger electronics or data acquisition system (DAQ), there is a hardware that is not time-critical, and can be run at a low priority. Slow control system (SCS) is used for setup and monitoring such hardware. SCS in a typical experiment are often used to setup and/or monitor components such as high voltage modules, temperature sensors, pressure gauges, leak detectors, RF generators, PID controllers etc. often from a large number of hardware vendors. Slow control system provides solution of the following tasks: control and monitoring of control parameters of detectors and other subsystems in the process of operation and setup of experimental facility, timely detection of failures in facility operation and alarming of emergency situations, monitoring of environmental parameters, archiving of facility parameters in database for further use in analysis of experimental data for the purpose of their correction.

This article outlines the architecture of the data management system (DMS), which is one of the core components of the SPD online filter’s middleware. The DMS automates the lifecycle management of experimental data during primary processing. The article also examines the functionality of a system that emulates the operation of the data acquisition system (DAQ)—SPD DAQ emulator. It provides a continuous data stream entering the SPD online filter, which allows for load testing of all middleware.

The double-differential cross sections of neutron production in ¹²⁴Xe + CsI collisions at 3.8 A GeV were measured at large polar angles with a compact time-of-flight spectrometer of the BM@N experiment. Preliminary results for the energy spectra of neutrons show near-isotropic emission of neutrons from target spectators. The spectra are well described by a moving source model with three components. The measured energy spectra are compared with predictions of the DCM-QGSM-SMM model. The low-energy part of the experimental spectra is not reproduced by the theoretical model, which significantly underestimates the yield of these neutrons.

The supramolecular organization in segmented polyurethanes modified with various copper-containing metal complexes was studied using the small-angle X-ray scattering method and atomic-force microscopy. It was found that in series of CuCl₂—N,N'-diethylhydroxylamine (MCS series) the distance between rigid blocks of segmented polyurethanes increases significantly, while in case of pure CuCl₂ series this parameter remains constant. The size of the rigid blocks increases in both cases.