Moscow University Physics Bulletin最新文献

{"title":"Thermodynamics of Charged Black Points in Vacuum Nonlinear Electrodynamics","authors":"V. A. Sokolov","doi":"10.3103/S0027134925702492","DOIUrl":"10.3103/S0027134925702492","url":null,"abstract":"<p>The paper analyzes the thermodynamic properties of a special state of charged black holes, in which the event horizon becomes pointlike and coincides with the singularity. It is shown that for such states, called black points, in contrast to Reissner–Nordström black holes, the third law of thermodynamics in Planck’s formulation is fulfilled. It is also shown that the formation of a black point is not a first-order phase transition. Considerable attention is paid to the special state of a black point with a doubly degenerate horizon, similar to the extreme state of a Reissner–Nordström black hole.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S703 - S710"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance Studies of Neutral Meson Measurements Possibilities with Precision Electromagnetic Calorimeter at U70 Facility","authors":"D. S. Blau,&nbsp;D. A. Averyanov,&nbsp;D. Yu. Peresunko","doi":"10.3103/S0027134925702613","DOIUrl":"10.3103/S0027134925702613","url":null,"abstract":"<p>An 256-channel electromagnetic calorimeter based on lead tungstate crystals is proposed for the studies of neutral meson and direct photon production and single-spin asymmetry measurements at the U70 accelerator facility at the National Research Centre ‘‘Kurchatov Institute’’—Institute of High Energy Physics. The U70 facility provides unique possibilities to perform such measurements with different types of polarized and unpolarized beams such as <span>(pi^{pm})</span>, K, p, <span>(bar{p})</span>, d, C. The results of Monte Carlo simulations of neutral meson spectra measurements are presented. The simulations are performed using GEANT4 tracking and realistic reconstruction in the calorimeter using events with single <span>(pi^{0})</span> meson with flat transverse momentum spectra as well as full PYTHIA8 generated events. Different geometry options are evaluated, and optimal positions of the calorimeter in the SPASCHARM experiment setup are discussed.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S788 - S794"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Functionality of the CompHEP 4.6 Package","authors":"E. E. Boos,&nbsp;V. E. Bunichev,&nbsp;M. N. Dubinin,&nbsp;L. V. Dudko,&nbsp;V. F. Edneral,&nbsp;A. P. Kryukov,&nbsp;V. I. Savrin","doi":"10.3103/S0027134925702698","DOIUrl":"10.3103/S0027134925702698","url":null,"abstract":"<p>A new version of the high energy physics computational package CompHEP has been released. This version adds the ability to perform calculations with complex form-factors, enabling the calculation of decay widths and scattering cross sections in next-to-leading order according to perturbation theory. A new CompHEP module has also been developed for the automatic, sequential calculation of arrays of decay widths and scattering cross sections as functions of multidimensional arrays of model parameter values. CompHEP now includes a module for statistical processing of results and the construction of confidence regions in the model parameter space. A new module for graphical presentation of results has been added for constructing one-dimensional, two-dimensional, and three-dimensional graphs in the ROOT package format.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S848 - S861"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Domain Adaptation of Neural Networks for Natural Water Diagnostics by Raman Spectroscopy","authors":"L. S. Utegenova,&nbsp;K. A. Buzanov,&nbsp;A. A. Guskov,&nbsp;S. A. Burikov,&nbsp;T. A. Dolenko,&nbsp;S. A. Dolenko","doi":"10.3103/S0027134925703023","DOIUrl":"10.3103/S0027134925703023","url":null,"abstract":"<p>Heavy metals, possessing high toxicity and the ability to bioaccumulate, pose a serious threat to aquatic ecosystems and human health. Therefore, the development of effective methods for monitoring the concentrations of heavy metals in natural waters is one of the urgent tasks of modern ecology. This work addresses the problem of determining the concentrations of Zn<span>({}^{2+})</span>, Cu<span>({}^{2+})</span>, Li<span>({}^{+})</span>, Fe<span>({}^{3+})</span>, Ni<span>({}^{2+})</span>, NH<span>({}_{4}^{+})</span>, SO<span>({}_{4}^{2-})</span>, and NO<span>({}_{3}^{-})</span> ions in aqueous solutions using Raman spectroscopy and artificial neural networks (NN). To adapt the NN to the specifics of the spectra of real natural waters from the Moscow River, Yauza, Bitza, and Setun Rivers (presence of luminescent background, suspended large particles in the medium, etc.), transfer learning and domain-adversarial learning algorithms were implemented. The proposed approach using domain adaptation significantly improved the accuracy of determining the concentrations of the studied ions in all river water solutions, reducing the mean absolute error by an average of 50<span>(%)</span>. Testing the method on Raman spectra of real natural waters showed that the developed technology allows determining ion concentrations with errors satisfactory for environmental monitoring.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :","pages":"S1217 - S1225"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Final-State Coulomb Interaction on (boldsymbol{B^{0}_{d,s}toell^{+}ell^{-}}), (boldsymbol{h^{0}ell^{+}ell^{-}}), (boldsymbol{V^{0}ell^{+}ell^{-}}) Decays","authors":"S. I. Manukhov,&nbsp;N. V. Nikitin","doi":"10.3103/S0027134925702741","DOIUrl":"10.3103/S0027134925702741","url":null,"abstract":"<p>We present a systematic analysis of Coulomb corrections for the interaction of charged leptons in the final state in lepton and semilepton decays of neutral <span>(B)</span>-mesons. The calculation is performed within the Furry picture. For scalar systems, a comparison is made between the nonrelativistic Gamow–Sommerfeld–Sakharov approximation, the exact relativistic method of Crater–Alstine–Sazdjian, and the Furry approach. Based on this comparison, an assumption is made about the applicability of the Furry method for calculating Coulomb corrections in the considered <span>(B)</span>-meson decays. The corrections are applied to the analysis of lepton (<span>(B^{0}_{d,s}toell^{+}ell^{-})</span>) and semilepton (<span>(B^{0}_{d,s}to h^{0},ell^{+}ell^{-})</span>, <span>(B^{0}_{d,s}to V^{0}ell^{+}ell^{-})</span>) channels. Differential, angular, and for the first time double differential distributions, along with partial decay widths, are calculated. For the <span>(B_{s}^{0}tomu^{+}mu^{-})</span> channel, Coulomb corrections improve the prediction of the partial width by 2<span>(%)</span>, improving the agreement with the LHCb/CMS experimental results within the current experimental (11<span>(%)</span>) and theoretical (5<span>(%)</span> lattice QM) errors. In the decays <span>(B^{0}to K^{0}mu^{+}mu^{-})</span> and <span>(B^{0}to K^{*0}mu^{+}mu^{-})</span>, Coulomb effects also reduce the discrepancies between theoretical predictions and experimental data (to less than <span>(1%)</span> and from 11 to 4<span>(%)</span>, respectively). Finally, for the decays <span>(B^{0}_{d,s}to{h^{0},V^{0}},tau^{+}tau^{-})</span>, the Coulomb correction reaches 7<span>(%)</span>, which is comparable to the uncertainties of the non-perturbative contributions of the strong interaction. The latter result suggests that the Coulomb correction may become significant in the search for new physics in rare <span>(B)</span>-meson decays, especially those involving <span>(tau)</span>-leptons in the final states.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S889 - S902"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Creation of Reasonable Robot Control Behavior in the Form of Executable Code","authors":"M. S. Skorokhodov,&nbsp;V. E. Latalin,&nbsp;R. B. Rybka,&nbsp;A. G. Sboev","doi":"10.3103/S002713492570314X","DOIUrl":"10.3103/S002713492570314X","url":null,"abstract":"<p>Growing possibilities of modern large language models discover the way to create new system for reasonable control of robot behavior using a limited communication with an operator. The system is proposed to convert human instructions into code snippets taking into account information from the robot’s world. This approach translates the complex interaction logic of the responses of the large language model into a code execution environment, resulting in improved reliability and predictability of system behavior. This system was evaluated using the set of handwritten instructions. This set consists of three parts: ‘‘direct’’ instructions relate to objects actually present in the environment, ‘‘abstract’’ instructions describe general tasks without specific details, and ‘‘out-of-space’’ instructions refer to actions beyond the robot’s capabilities or mention objects not shown in its environment. Large language models, such as Deepseek, Qwen, and GPT, were tested with the different types of training and the number of parameters. The results demonstrate that generating control instructions in the form of executable code increases the flexibility of robot control and reduces the risk of hallucinations, particularly during arithmetic operations.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :","pages":"S1165 - S1175"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning Model for Ventilatory Thresholds Prediction","authors":"A. S. Minkin","doi":"10.3103/S0027134925703114","DOIUrl":"10.3103/S0027134925703114","url":null,"abstract":"<p>One of the challenges in determining the physical fitness of cosmonauts is assessing the ventilatory thresholds (VTs), which can be identified through the analysis of gas exchange data collected during cardiopulmonary exercise test. The prediction of VTs often relies on visual inspection of graphical plots of ventilatory equivalents for gas exchange data. The result of V-slope and regression based methods for estimation of ventilatory anaerobic threshold significantly depends on data preprocessing. So, the procedure of VTs estimation can be classified as a poorly formalized problem. That is why, in this paper, we propose a machine learning model based on decision trees to predict VTs. The purpose of the study is to select features by their importance and present an interpretable model for VTs prediction, using minimal data preprocessing. An iterative training of decision trees with different hyperparameters was used to choose significant features from the expert labeled data. The feature importance evaluation showed that, besides basic gas exchange parameters like oxygen uptake, carbon dioxide production, and ventilatory equivalents, metrics derived from indirect calorimetry and measures of lung capacity (e.g., tidal volume, breathing reserve) are also important for VTs prediction. A random forest model was used with the final set of the most relevant features to predict the VTs with an accuracy of approximately 90<span>(%)</span>. Such a model can be applied to predict VTs for datasets not used in training and to provide useful insights and conclusions based on the data structure. A data clustering approach guided by the accuracy of a machine learning model is proposed.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :","pages":"S1157 - S1164"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using Machine Learning Methods for Joint Processing of Data from Multiple Semiconductor Gas Sensors","authors":"I. V. Isaev,&nbsp;K. N. Chernov,&nbsp;S. A. Dolenko,&nbsp;V. V. Krivetskiy","doi":"10.3103/S0027134925703060","DOIUrl":"10.3103/S0027134925703060","url":null,"abstract":"<p>This study addresses the problem of environmental monitoring of air in cities and industrial areas, which consists of detecting gases and volatile organic compounds using semiconductor gas sensors. To provide selectivity in the detection of certain gases, as well as high temporal resolution of the sensors, nonlinear temperature operating conditions were used—the so-called heating dynamics. Due to high complexity of physical and chemical models describing the processes of interaction between gases and sensors, machine learning methods based on the use of physical experiment data were used to process the sensor response. To provide additional selectivity in the detection of specific gases, this study considers simultaneous use of data from multiple semiconductor sensors with various doping components with building machine learning models capable of providing joint processing. Based on the results of the computational experiments, it was shown that in many cases, simultaneous use of data from multiple sensors improves the quality of the regression solution for determining gas concentrations. Detailed conclusions were also drawn regarding the selection of optimal sensor combinations, heating dynamics, and machine learning methods, both for each specific gas and for all gases.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :","pages":"S1226 - S1233"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inflationary Slow-Roll Parameters in the Jordan Frame for Cosmological (boldsymbol{F(R)}) Gravity Models","authors":"V. R. Ivanov","doi":"10.3103/S002713492570239X","DOIUrl":"10.3103/S002713492570239X","url":null,"abstract":"<p>\u0000 <span>(F(R))</span> inflationary models are analyzed without the Weyl transformation to the Einstein frame. Sufficient conditions for existence of global inflationary attractors in <span>(F(R))</span> models are provided. Following that, the procedure for calculating inflationary observables completely in the original, Jordan, frame is given. The described procedure is used to analyze a new <span>(F(R))</span> inflationary model (a one-parameter deformation of the Starobinsky model), which is shown to provide predictions in good agreement with the recent ACT data.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S614 - S623"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Massive Domain Wall Fermions","authors":"G. A. Krasukov,&nbsp;O. V. Pavlovsky","doi":"10.3103/S0027134925702431","DOIUrl":"10.3103/S0027134925702431","url":null,"abstract":"<p>In this study we consider a two-dimensional Dirac model with inhomogeneous energy gap. New generalizations of the domain-wall fermions formalism are proposed. It is shown that the step-terrace surface structure of the domain wall leads to the appearance of localized massive fermion states.</p>","PeriodicalId":711,"journal":{"name":"Moscow University Physics Bulletin","volume":"80 :\nHigh","pages":"S647 - S654"},"PeriodicalIF":0.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}