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This paper presents the multiplicity of neutral and charged hadrons produced in 90 GeV$/c$ proton-carbon interactions from a dataset taken by the NA61/SHINE experiment in 2017. Particle identification via dE/dx was performed for the charged hadrons $\pi^\pm$, $K^\pm$, and $p / \bar{p}$; the neutral hadrons $K^0_S$, $\Lambda$, and $\bar{\Lambda}$ were identified via an invariant mass analysis of their decays to charged hadrons. Double-differential multiplicity results as a function of laboratory momentum and polar angle are presented for each particle species; these results provide vital constraints on the predicted neutrino beam flux for current and future long-baseline neutrino oscillation experiments.

The results obtained by estimating the contribution of $^8$Be and $^9$B nuclei to the coherent dissociation of $^{10}$C, $^{10}$B, and $^{12}$C relativistic nuclei in nuclear track emulsions (``white'' stars) are presented. The selection of ``white'' stars accompanied by $^9$B leads to a distinct peak appearing in the distribution of the excitation energy of 2$\alpha$2$p$ ensembles and having a maximum at 4.1 $\pm$ 0.3 MeV. A $^8$Be nucleus manifests itself in the coherent-dissociation reaction $^{10}$B $\to$ 2He + H with a probability of (25 $\pm$ 5)\%, (14 $\pm$ 3)\% of it being due to $^9$B decays. The ratio of the branching fractions of the $^9$B + $n$ and $^9$Be + $p$ mirror channels is estimated at 6 $\pm$ 1. An analysis of the relativistic dissociation of $^{12}$C nuclei in a nuclear track emulsion revealed nine 3$\alpha$ events corresponding to the Hoyle state.

The structural features of $^{10}$B are studied by analyzing the dissociation of nuclei of this isotope at an energy of 1 A GeV in nuclear track emulsion. The fraction of the $^{10}$B $\to$ 2He + H channel in the charge state distribution of fragments is 78\%. It was determined based on the measurements of fragment emission angles that unstable $^{8}$Be$_{g.s.}$ nuclei appear with a probability of (26 $\pm$ 4)\%, and (14 $\pm$ 3)\% of them are produced in decays of an unstable $^9$B$_{g.s.}$ nucleus. The Be + H channel was suppressed to approximately 1\%., Comment: Published as proceedings of The International Session-Conference of SNP PSD RAS "Physics of Fundamental Interactions"

The results of the study of unstable states in relativistic dissociation of isotopes $^{9,7}$Be, $^{10}$B, $^{12,11,10}$C, $^{14}$N and $^{16}$O in nuclear emulsion have been summarized. Their decays are identified in distributions by invariant masses determined by fragment emission angles in the velocity conservation approximation. The observed diversity enables us to assume universality in the formation of nuclear-molecular states near the bond thresholds as a consequence of coalescence of emerging $\alpha$-particles and nucleons., Comment: The article to be published in International Journal of Modern Physics E as proceedings of the LXXIV International conference Nucleus-2024: Fundamental problems and applications (https://indico.jinr.ru/event/4304/page/1972-publication-information)

In medical diagnostics, accurate uncertainty estimation for neural-based models is essential for complementing second-opinion systems. Despite neural network ensembles' proficiency in this problem, a gap persists between actual uncertainties and predicted estimates. A major difficulty here is the lack of labels on the hardness of examples: a typical dataset includes only ground truth target labels, making the uncertainty estimation problem almost unsupervised. Our novel approach narrows this gap by integrating expert assessments of case complexity into the neural network's learning process, utilizing both definitive target labels and supplementary complexity ratings. We validate our methodology for blood typing, leveraging a new dataset "BloodyWell" unique in augmenting labeled reaction images with complexity scores from six medical specialists. Experiments demonstrate enhancement of our approach in uncertainty prediction, achieving a 2.5-fold improvement with expert labels and a 35% increase in performance with estimates of neural-based expert consensus.

The paper presents a study of methods for extracting information about dialogue participants and evaluating their performance in Russian. To train models for this task, the Multi-Session Chat dataset was translated into Russian using multiple translation models, resulting in improved data quality. A metric based on the F-score concept is presented to evaluate the effectiveness of the extraction models. The metric uses a trained classifier to identify the dialogue participant to whom the persona belongs. Experiments were conducted on MBart, FRED-T5, Starling-7B, which is based on the Mistral, and Encoder2Encoder models. The results demonstrated that all models exhibited an insufficient level of recall in the persona extraction task. The incorporation of the NCE Loss improved the model's precision at the expense of its recall. Furthermore, increasing the model's size led to enhanced extraction of personas.

Using angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT), an experimental and theoretical study of changes in the electronic structure (dispersion dependencies) and corresponding modification of the energy band gap at the Dirac point (DP) for topological insulator (TI) $\mathrm{Mn}_{1-x} \mathrm{Ge}_x \mathrm{Bi}_2 \mathrm{Te}_4$ have been carried out with gradual replacement of magnetic Mn atoms by non-magnetic Ge atoms when concentration of the latter was varied from 10$\%$ to 75$\%$. It was shown that when Ge concentration increases then the bulk band gap decreases and reaches zero plateau in the concentration range of 45$\%$-60$\%$ while non-topological surface states (TSS) are present and exhibit an energy splitting of 100 and 70 meV in different types of measurements. It was also shown that TSS disappear from the measured band dispersions at a Ge concentration of about 40$\%$. DFT calculations of $\mathrm{Mn}_{1-x} \mathrm{Ge}_x \mathrm{Bi}_2 \mathrm{Te}_4$ band structure were carried out to identify the nature of observed band dispersion features and to analyze a possibility of magnetic Weyl semimetal state formation in this system. These calculations were performed for both antiferromagnetic (AFM) and ferromagnetic (FM) ordering types while the spin-orbit coupling (SOC) strength was varied or a strain (compression or tension) along the $c$-axis was applied. Calculations show that two different series of topological phase transitions (TPTs) may be implemented in this system depending on the magnetic ordering. At AFM ordering transition between TI and trivial insulator phase goes through the Dirac semimetal state, whereas for FM phase such route admits three intermediate states instead of one (TI - Dirac semimetal - Weyl semimetal - Dirac semimetal - trivial insulator).

Background: The aim of this study was to investigate the role of clinical, dosimetric and pretherapeutic magnetic resonance imaging (MRI) features for lesion-specific outcome prediction of stereotactic radiotherapy (SRT) in patients with brain metastases from malignant melanoma (MBM). Methods: In this multicenter, retrospective analysis, we reviewed 517 MBM from 130 patients treated with SRT (single fraction or hypofractionated). For each gross tumor volume (GTV) 1576 radiomic features (RF) were calculated (788 each for the GTV and for a 3 mm margin around the GTV). Clinical parameters, radiation dose and RF from pretherapeutic contrast-enhanced T1-weighted MRI from different institutions were evaluated with a feature processing and elimination pipeline in a nested cross-validation scheme. Results: Seventy-two (72) of 517 lesions (13.9%) showed a local failure (LF) after SRT. The processing pipeline showed clinical, dosimetric and radiomic features providing information for LF prediction. The most prominent ones were the correlation of the gray level co-occurrence matrix of the margin (hazard ratio (HR): 0.37, confidence interval (CI): 0.23-0.58) and systemic therapy before SRT (HR: 0.55, CI: 0.42-0.70). The majority of RF associated with LF was calculated in the margin around the GTV. Conclusions: Pretherapeutic MRI based RF connected with lesion-specific outcome after SRT could be identified, despite multicentric data and minor differences in imaging protocols. Image data analysis of the surrounding metastatic environment may provide therapy-relevant information with the potential to further individualize radiotherapy strategies.

A new approach is given to property $(P_q)$ defined by Catlin for $q=1$ in a global and by Sibony in a local context, subsequently extended by Fu-Straube for $q>1$. This property is known to imply compactness and global regularity in the $\bar\partial$-Neumann problem by a result of Kohn-Nirenberg, as well as condition $R$ by a result of Bell-Ligocka. In particular, we provide a self-contained proof of property $(P_q)$ for pseudoconvex hypersurfaces of finite D'Angelo $q$-type, the case originally studied by Catlin. Moreover, our proof covers more general classes of hypersurfaces inspired by a recent work of Huang-Yin. Proofs are broken down into isolated steps, some of which do not require pseudoconvexity. Our tools include: a new multitype invariant based on distinguished nested sequences of $(1,0)$ subbundles, defined in terms of derivatives of the Levi form; real and complex formal orbits; $k$-jets of functions relative to pairs of formal submanifolds; relative contact orders generalizing the usual contact orders; a new notion of supertangent vector fields having higher than expected relative contact orders; and a formal variant of a result by Diederich-Forn\ae ss arising as a key step in their proof of Kohn's ideal termination in the real-analytic case.

Measurements of $K_S^0$ meson production via its $\pi^{+} \pi^{-}$ decay mode in inelastic $\textit{p+p}$ interactions at incident projectile momenta of 31, 40 and 80 GeV/$c$ ($\sqrt{s_{NN}}=7.7, 8.8$ and $12.3$ GeV, respectively) are presented. The data were recorded by the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicities of $K_S^0$ mesons were determined to be $(5.95 \pm 0.19 (stat) \pm 0.22 (sys)) \times 10^{-2}$ at 31 GeV/$c$, $(7.61 \pm 0.13 (stat) \pm 0.31 (sys)) \times 10^{-2}$ at 40 GeV/$c$ and $(11.58 \pm 0.12 (stat) \pm 0.37 (sys)) \times 10^{-2}$ at 80 GeV/$c$. The results on $K^{0}_{S}$ production are compared with model calculations (Epos1.99, SMASH 2.0 and PHSD) as well as with published data from other experiments., Comment: arXiv admin note: substantial text overlap with arXiv:2106.07535

Inclusive spectra of the kaons produced in $Ar Sc$ collisions as functions of their transverse momentum $p_T$ at mid-rapidity have been calculated within the approach based on the assumption of the similarity of inclusive spectra of the hadrons produced in nucleus-nucleus collisions at their small transverse momenta in the mid-rapidity region taking into account the quark-gluon dynamics in nucleon-nucleon interactions. This article gives a satisfactory description of NA61/SHINE data on $p_T$-spectra of the $K^\pm$ mesons produced in $ArSc$ collisions at the mid-rapdity ($y\simeq$ 0)., Comment: To be published in EPJ A journal

In this paper we compute the Jordan constants of the Cremona group of rank two over all fields of characteristic zero., Comment: 12 pages

In this paper, we find the maximum values that the Jordan constant of the automorphism group of a smooth two-dimensional rational quadric over a field of characteristic zero can attain, depending on the arithmetic properties of a field., Comment: 18 pages

The critical point of strongly interacting matter is searched for at the CERN SPS by the NA61/SHINE experiment in central $^{40}$Ar +$^{45}$Sc collisions at 13$A$, 19$A$, 30$A$, 40$A$, and 75$A$ GeV/$c$. The dependence of the second-order scaled factorial moments of proton multiplicity distributions on the number of subdivisions in transverse momentum space is measured. The intermittency analysis uses statistically independent data sets for every subdivision in transverse and cumulative-transverse momentum variables. The results obtained do not indicate the searched intermittent pattern. An upper limit on the fraction of correlated protons and the intermittency index is obtained based on a comparison with the Power-law Model., Comment: 38 pages, 20 figures

Research of cosmic rays at the Physical Institute of the USSR Academy of Sciences resulted in the construction of the JINR Synchrophasotron. For this purpose the Electrophysical Laboratory of the USSR Academy of Sciences was founded in 1953, which became part of JINR in 1956 as the High Energy Laboratory. The initial milestones to develop experiments at the Laboratory on the Synchrophasotron are presented. Leaders and key participants in the experiments are highlighted, as well as the lessons and results relevant today., Comment: To be published in Proceedings of https://indico.jinr.ru/event/3694/ (PEPAN/EChAYa)

This paper presents the energy dependence of multiplicity and net-electric charge fluctuations in p+p interactions at beam momenta 20, 31, 40, 80, and 158 GeV/c. Results are corrected for the experimental biases and quantified with the use of cumulants and factorial cumulants. Cumulant ratios are an essential tool in the search for the critical point of strongly interacting matter in heavy ion collisions. Measurements performed in p+p interactions provide a vital baseline estimation in these studies. The measured signals are compared with the string hadronic models EPOS1.99 and FTFP-BERT., Comment: 28 pages, 10 figures. The version to be published in Eur. Phys. J. C

On the example of the exoplanet HD 189733 an influence of stellar activity on the efficiency of the plasma mechanism of radio emission generation of the exoplanet and the properties of this emission are considered. The plasma generation mechanism can be effectively implemented in the plasmasphere of exoplanets with a weak magnetic field and a relatively high electron plasma density, when the electron cyclotron maser is not efficient. The plasma mechanism depends essentially on the parameters of the plasma and involves the generation of plasma waves by energetic electrons and a conversion of these waves into electromagnetic radiation. The stellar wind can significantly modify the exoplanet plasmasphere, which was not taken into account in the first studies of the plasma mechanism in the plasmasphere of HD 189733b. In present study we used a three-dimensional model of the interaction of the exoplanet HD189733b with the stellar wind for cases of moderate and intense stellar winds. The study shows that the implementation of plasma mechanism is possible at any intensity of the stellar wind. However, depending on the intensity, the requirements for the parameters of plasma mechanism change. In particular, the plasma waves energy which is required to generate the radio emission available for registration by modern radio telescopes changes. Besides, the frequency range of the radio emission changes. The latter will make it possible to use the detected radio emission as an indicator of the activity of the parent star.

Strong interactions preserve an approximate isospin symmetry between up ($u$) and down ($d$) quarks, part of the more general flavor symmetry. In the case of $K$ meson production, if this isospin symmetry were exact, it would result in equal numbers of charged ($K^+$ and $K^-$) and neutral ($K^0$ and $\overline K^{\,0}$) mesons in the final state. Here, we report results on the relative abundance of charged over neutral $K$ meson production in argon and scandium nuclei collisions at a center-of-mass energy of 11.9 GeV per nucleon pair. We find that the production of $K^+$ and $K^-$ mesons at mid-rapidity is $(18.4\pm 6.1)\%$ higher than that of the neutral $K$ mesons. Although with large uncertainties, earlier data on nucleus-nucleus collisions in the collision center-of-mass energy range $2.6 < \sqrt{s_{NN}} < 200$~\GeV are consistent with the present result. Using well-established models for hadron production, we demonstrate that known isospin-symmetry breaking effects and the initial nuclei containing more neutrons than protons lead only to a small (few percent) deviation of the charged-to-neutral kaon ratio from unity at high energies. Thus, they cannot explain the measurements. The significance of the flavor-symmetry violation beyond the known effects is 4.7$\sigma$ when the compilation of world data with uncertainties quoted by the experiments is used. New systematic, high-precision measurements and theoretical efforts are needed to establish the origin of the observed large isospin-symmetry breaking., Comment: The paper includes updates based on the final results of $K^+$ and $K^-$ yields published in Eur. Phys. J.C 84 (2024) 4, 416

An explanation is proposed for the appearance of slowly drift shadow bursts in the dynamic spectrum of Jupiter against the background of decameter radio emission with a quasi-harmonic structure. Background radio emission is caused by hot ions with a loss cone type distribution function, which generate ion cyclotron waves due to the effect of double plasma resonance. A flow of hot ions with a distribution function of the Maxwell type is injected into the source region, fills the loss cone of generating ions and interrupts the generation of ion cyclotron waves due to the filling of the loss cone. The condition under which instability breaks down is obtained, and the optimal values of the parameters of the injected ions necessary for the occurrence of bursts in absorption are determined.

The article presents a review of studying unstable states in the relativistic dissociation of nuclei $^{10}$B, $^{11,12}$C, $^{16}$O, $^{22}$Ne, $^{28}$Si, $^{84}$Kr and $^{197}$Au in the energy range from hundreds of MeV/nucleon to several tens of GeV/nucleon using the nuclear track emulsion method. A systematic study of the fragmentation of incident nuclei with multiple formation of the lightest fragments of He and H. This made it possible to study the dynamics of unstable nuclear states of $^8$Be, the Hoyle state and the 4$\alpha$-particle state of the $^{16}$O nucleus above the threshold in the relativistic dissociation of nuclei due to precision measurements of fragment emission angles. It is shown that to reconstruct the relativistic decays of unstable nuclei in a nuclear track emulsion, it is sufficient to determine the invariant mass of the system of He and H fragments in the approximation of conservation of momentum per nucleon of the parent nucleus. This approach allows one to search for more complex nuclear states. An indication has been obtained of growing probability to detect $^8$Be with increasing the number of relativistic $\alpha$ particles in the event., Comment: The article to be published in PEPAN (ECHAYA, Physics of Elementary Particles and Atomic Nuclei) journal as proceedings of the XXVth International Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics and Quantum Chromodynamics" (https://relnp.jinr.ru/ishepp/)

Biaxial tensile device for transport study of layered materials is described. The device is mounted on the standard 24 pin zero force connector and can be moved between various setups. Compact design of the device makes it suitable for a wide range of studies. In our case, it is placed inside a 50 mm diameter chamber in closed-circle refrigerator and is used in the temperature range 9 K - 310 K. A sample is glued in the center of a polyimide cruciform substrate, the ends of which are connected to a tension system driven by four computer-controlled stepper motors providing tensile force up to 30 N. Computer simulation results and their experimental verification show that tensile strain along one axis depends on the tensile load along perpendicular direction, and this dependence turns out to be relatively strong and exceeds 40%. The operation of the device is demonstrated by studying the effect of deformation on the electrical conductivity of a layered compound 2H-NbS2., Comment: New version: 6 pages (one more page), 8 figures (2 new figures)

Let $X_1,\dots, X_n,\dots$ be i.i.d.\ $d$-dimensional random vectors with common distribution $F$. Then $S_n = X_1+\dots+X_n$ has distribution $F^n$ (degree is understood in the sense of convolution). Let $$ \rho_{\mathcal{C}_d}(F,G) = \sup_A |F\{A\} - G\{A\}|, $$ where the supremum is taken over all convex subsets of $\mathbb R^d$. Basic result is as follows. For any nontrivial distribution $F$ there is $c_1(F)$ such that $$ \rho_{\mathcal{C}_d}(F^n, F^{n+1})\leq \frac{c_1(F)}{\sqrt n} $$ for any natural $n$. The distribution $F$ is called trivial if it is concentrated on a hyperplane that does not contain the origin. Clearly, for such $F$ $$ \rho_{\mathcal{C}_d}(F^n, F^{n+1}) = 1. $$ A similar result for the Prokhorov distance is also obtained. For any $d$-dimensional distribution~$F$ there is a $c_2(F)>0$ that depends only on $F$ and such that \begin{multline}\nonumber (F^n)\{A\}\le (F^{n+1})\{A^{c_2(F)}\}+\frac{c_2(F)}{\sqrt{n}} \text{and}\quad (F^{n+1})\{A\}\leq (F^n)\{A^{c_2(F)}\}+\frac{c_2(F)} {\sqrt{n}} \end{multline} for any Borel set $ A $ for all positive integers $n$. Here $A^{\varepsilon }$ is $ \varepsilon $-neighborhood of the set $ A $., Comment: 15 pages

A commercial quantum key distribution (QKD) system needs to be formally certified to enable its wide deployment. The certification should include the system's robustness against known implementation loopholes and attacks that exploit them. Here we ready a fiber-optic QKD system for this procedure. The system has a prepare-and-measure scheme with decoy-state BB84 protocol, polarisation encoding, qubit source rate of 312.5 MHz, and is manufactured by QRate. We detail its hardware and post-processing. We analyse the hardware for known implementation loopholes, search for possible new loopholes, and discuss countermeasures. We then amend the system design to address the highest-risk loopholes identified. We also work out technical requirements on the certification lab and outline its possible structure., Comment: 34 pages, 11 figures, 2 tables. Minor improvements after peer review. Accepted to Phys. Rev. Appl