Персона: Окороков, Виталий Алексеевич
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Институт общей профессиональной подготовки (ИОПП)
Миссией Института является:
фундаментальная базовая подготовка студентов, необходимая для получения качественного образования на уровне требований международных стандартов;
удовлетворение потребностей обучающихся в интеллектуальном, культурном, нравственном развитии и приобретении ими профессиональных знаний; формирование у студентов мотивации и умения учиться; профессиональная ориентация школьников и студентов в избранной области знаний, формирование способностей и навыков профессионального самоопределения и профессионального саморазвития.
Основными целями и задачами Института являются:
обеспечение высококачественной (фундаментальной) базовой подготовки студентов бакалавриата и специалитета; поддержка и развитие у студентов стремления к осознанному продолжению обучения в институтах (САЕ и др.) и на факультетах Университета; обеспечение преемственности образовательных программ общего среднего и высшего образования; обеспечение высокого качества довузовской подготовки учащихся Предуниверситария и школ-партнеров НИЯУ МИФИ за счет интеграции основного и дополнительного образования;
учебно-методическое руководство общеобразовательными кафедрами Института, осуществляющими подготовку бакалавров и специалистов по социо-гуманитарным, общепрофессиональным и естественнонаучным дисциплинам, обеспечение единства требований к базовой подготовке студентов в рамках крупных научно-образовательных направлений (областей знаний).
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Окороков
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Виталий Алексеевич
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- ПубликацияТолько метаданныеGlobal and local polarization of A hyperons in Au plus Au collisions at 200 GeV from STAR(2019) Niida, T.; Adam, J.; Adamczyk, L.; Adams, J. R.; Alekseev, I.; Brandin, A. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичNew results on global polarization of A hyperons in Au+Au collisions at root s(NN) = 200 GeV reveal non-zero signal on the order of a few tenths of a percent. Compared with lower energy results, the current measurement shows that the polarization decreases at higher collision energy, the trend being well reproduced by theoretical calculations. The polarization is found to be larger in more peripheral collisions, as well as in the in-plane than in the out-of-plane direction. The signal seems to depend on the asymmetry between positive and negative charge in each event, which may indicate an influence of the axial current induced by the magnetic field. In addition, the first measurement of a local polarization along the beam direction was performed. The results show a quadrupole modulation relative to the second-order event plane, as expected from the elliptic flow.
- ПубликацияТолько метаданныеFirst Measurement of Lambda(c) Baryon Production in Au plus Au Collisions at root s(NN)=200 GeV(2020) Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Alekseev, I.; Brandin, A. V.; Khyzhniak, Y. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичWe report on the first measurement of the charmed baryon Lambda(+/-)(c) production at midrapidity (vertical bar y vertical bar < 1) in Au + Au collisions root s(NN) = 200 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The A(c)/D-0 [denoting (Lambda(+)(c) + Lambda(-)(c))/(D-0 + (D) over bar (0))] yield ratio is measured to be 1.08 +/- 0.16 (stat) 0.26 (sys) in the 0%-20% most central Au + Au collisions for the transverse momentum (p(T)) range 3 < p(T) < 6 GeV/c. This is significantly larger than the PYTHIA model calculations for p + p collisions. The measured A(c)/D-0 ratio, as a function of p(T) and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au + Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured Lambda(c)/D-0 ratio.
- ПубликацияТолько метаданныеMeasurement of D-0-meson + hadron two-dimensional angular correlations in Au plus Au collisions at root s(NN)=200 GeV(2020) Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Alekseev, I.; Brandin, A. V.; Khyzhniak, Y. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичOpen heavy-flavor hadrons provide unique probes of the medium produced in ultrarelativistic heavy-ion collisions. Due to their increased mass relative to light-flavor hadrons, long lifetime, and early production in hard-scattering interactions, they provide access to the full evolution of the partonic medium formed in heavy-ion collisions. This paper reports two-dimensional (2D) angular correlations between neutral D mesons and unidentified charged particles produced in minimum-bias Au+Au collisions at root s(NN) = 200 GeV. D-0 and D-0 mesons are reconstructed via their weak decay to K--/+ pi(+/-) using the Heavy Flavor Tracker in the Solenoidal Tracker at RHIC experiment. Correlations on relative pseudorapidity and azimuth (Delta(eta), Delta(phi)) are presented for peripheral, midcentral, and central collisions with D-0 transverse momentum from 2-10 GeV/c. Attention is focused on the 2D peaked correlation structure near the triggered D-0 meson, the near-side (NS) peak, which serves as a proxy for a charm-quark-containing jet. The correlated NS yield of charged particles per D-0 meson and the 2D widths of the NS peak increase significantly from peripheral to central collisions. These results are compared with similar correlations using unidentified charged particles, consisting primarily of light-flavor hadrons, at similar trigger particle momenta. Similar per-trigger yields and widths of the NS correlation peak are observed. The present results provide additional evidence that D-0 mesons undergo significant interactions with the medium formed in heavy-ion collision and show, for the first time, significant centrality evolution of the NS 2D peak in the correlations of particles associated with a heavy-flavor hadron produced in these collisions.
- ПубликацияТолько метаданныеUpsilon measurements in Au plus Au collisions at root S-NN=200 GeV with the STAR experiment(2019) Wang, P. F.; Adam, J.; Adamczyk, L.; Adams, J. R.; Alekseev, I.; Brandin, A. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичWe present the latest measurements of Upsilon production in Au+Au collisions at root S-NN = 200 GeV via both di-muon and di-electron decay channels by the STAR experiment at RHIC. With the addition of the 2016 data set to those taken in 2011 and 2014, the precision of Upsilon measurements is significantly improved compared to previous preliminary results, especially for the excited Upsilon states. The nuclear modification factors for the ground and excited Upsilon states are shown as a functions of transverse momentum or centrality, and are compared to results from the LHC as well as to theoretical calculations.
- ПубликацияТолько метаданныеMeasurements of open charm production in Au plus Au collisions at root s(NN)=200 GeV with the STAR experiment at RHIC(2019) Radhakrishnan, S.; Adam, J.; Adamczyk, L.; Adams, J. R.; Alekseev, I.; Brandin, A. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичWe report in these proceedings on the measurements of collision centrality and transverse momentum (p(T)) dependences of the Lambda(+/-)(c) production in Au+Au collisions at root s(NN) = 200 GeV, using the STAR Heavy Flavor Tracker (HFT). The Lambda(+/-)(c) signal significance is greatly improved with the addition of the high-statistics data set collected in 2016 and the use of a supervised machine learning method for topological reconstruction of the decay vertices. The measured Lambda(+/-)(c)/D-0 ratio shows a significant enhancement compared to the PYTHIA prediction for p+p collisions, across the measured p(T) range. We also report on the updated measurements of D-0 nuclear modification factors R-AA and R-CP using the 2014 data with the HFT. The measured D-0 R-AA in central collisions is lower than unity across the p(T) interval of the measurement. The D-0 yields show strong suppression at high p(T) (> 6 GeV/c) in central collisions, consistent with that of light flavor hadrons. The c (c) over bar production cross section per binary nucleon collision at midrapidity in Au+Au collisions at 200 GeV is extracted based on the various charm hadron measurements by STAR. It is observed that while the charm hadrochemistry is significantly modified in Au+Au collisions compared to p+p collisions, the c (c) over bar production cross section at midrapidity remains consistent between Au+Au and p+p collisions.
- ПубликацияТолько метаданныеBeam-energy dependence of identified two-particle angular correlations ins root s(NN)=7.7-200 GeV Au + Au collisions(2020) Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Alekseev, I.; Brandin, A. V.; Khyzhniak, Y. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V.; Strikhanov, M. N.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичThe two-particle angular correlation functions, R-2, of pions, kaons, and protons in Au + Au collisions at A root s(NN) = 7 . 7 , 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV were measured by the STAR experiment at the BNL Relativistic Heavy Ion Collider. These correlations were measured for both like-sign and unlike-sign charge combinations and versus the centrality. The correlations of pions and kaons show the expected near-side (i.e., at small relative angles) peak resulting from short-range mechanisms. The amplitudes of these short-range correlations decrease with increasing beam energy. However, the proton correlation functions exhibit strong anticorrelations in the near-side region. This behavior is observed for the first time in an A + A collision system. The observed anticorrelation is p(T) independent and decreases with increasing beam energy and centrality. The experimental results are also compared to the Monte Carlo models UrQMD, Hijing, and AMPT.
- ПубликацияТолько метаданныеThe STAR BES-II and Forward Rapidity Physics and Upgrades(2019) Yang, Q.; Adam, J.; Adamczyk, L.; Adams, J. R.; Alekseev, I.; Brandin, A. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичThe second phase of the Beam Energy Scan at RHIC, BES-II, is scheduled to start in 2019 and will explore the high baryon density region of the QCD phase diagram with precision measurements. The detector upgrades will enhance some of the key measurements by extending STAR's kinematic reach, like the kurtosis of net-protons distribution which could pinpoint the position of a critical point. The upgrades currently under way comprise: the replacement of the inner TPC sectors, the Event Plane Detector (EPD) and the end-cap TOR Building on these upgrades STAR is planning to further enhance its detector capabilities by installing a Forward Calorimeter System (FCS) integrating an electromagnetic and hadronic calorimeter and a Forward Tracking System (FTS) combining 3 Silicon mini-strip disks and 4 Small-Strip Thin Gap Chamber (sTGC) wheels. The forward upgrades are motivated by studying the initial state of nucleons and nuclei and the exploration of cold QCD physics in the very high and low x regions. This contribution will highlight these upgrades and some of the physics opportunities that they allow.
- ПубликацияТолько метаданныеHollowness effect and entropy in high energy elastic scattering(2020) Campos, S. D.; Okorokov, V. A.; Окороков, Виталий АлексеевичThis paper presents a qualitative explanation for the hollowness effect based on the inelastic overlap function, claiming this result is a consequence of fundamental thermodynamic processes. Using the Tsallis entropy, one identifies the entropic indexwwith the ratio of the collision energy to critical one in the total cross-section. The integrated probability density function is replaced by the inelastic overlap function, which represents the probability of occurrence of an inelastic event depending on both the collision energy and impact parameter. The Coulomb potential, as well as the confinement potential, are used as naive approaches to describe the (internal) energy of the colliding hadrons. The Coulomb potential in the impact parameter picture is not able to furnish any reliable physical result near the forward direction. However, the confinement potential in the impact parameter space results in the hollowness effect shown by the inelastic overlap function near the forward direction.
- ПубликацияТолько метаданныеBeam energy dependence of net-Lambda fluctuations measured by the STAR experiment at the BNL Relativistic Heavy Ion Collider(2020) Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Alekseev, I.; Brandin, A. V.; Khyzhniak, Y. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий ВладимировичThe measurements of particle multiplicity distributions have generated considerable interest in understanding the fluctuations of conserved quantum numbers in the quantum chromodynamics (QCD) hadronization regime, in particular near a possible critical point and near the chemical freeze-out. Net-protons and net-kaons have been used as proxies for the net-baryon number and net-strangeness, respectively. We report the measurement of efficiency- and centrality-bin width-corrected cumulant ratios (C-2/C-1,C-3/C-3) of net-A distributions, in the context of both strangeness and baryon number conservation, as a function of collision energy, centrality, and rapidity. The results are for Au + Au collisions at five beam energies (root s(NN) = 19.6, 27, 39, 62.4, and 200 GeV) recorded with the Solenoidal Tracker at RHIC (STAR). We compare our results to the Poisson and negative binomial (NBD) expectations, as well as to ultrarelativistic quantum molecular dynamics (UrQMD) and hadron resonance gas (HRG) model predictions. Both NBD and Poisson baselines agree with data within the statistical and systematic uncertainties. UrQMD describes the measured net-A C-1 and C-3 at 200 GeV reasonably well but deviates from C-2, and the deviation increases as a function of collision energy. The ratios of the measured cumulants show no features of critical fluctuations. The chemical freeze-out temperatures extracted from a recent HRG calculation, which was successfully used to describe the net-proton, net-kaon, and net-charge data, indicate A freeze-out conditions similar to those of kaons. However, large deviations are found when comparing with temperatures obtained from net-proton fluctuations. The net-A cumulants show a weak but finite dependence on the rapidity coverage in the acceptance of the detector, which can be attributed to quantum number conservation.
- ПубликацияТолько метаданныеBeam-energy dependence of the directed flow of deuterons in Au+Au collisions(2020) Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Alekseev, I.; Brandin, A. V.; Khyzhniak, Y. V.; Kochenda, L.; Kravtsov, P.; Nigmatkulov, G.; Okorokov, V. A.; Strikhanov, M.; Taranenko, A.; Алексеев, Игорь Геннадьевич; Брандин, Андрей Владимирович; Нигматкулов, Григорий Александрович; Окороков, Виталий Алексеевич; Стриханов, Михаил Николаевич; Тараненко, Аркадий Владимирович© 2020 American Physical Society.We present a measurement of the first-order azimuthal anisotropy v1 of deuterons from Au+Au collisions at sNN=7.7, 11.5, 14.5, 19.6, 27, and 39 GeV recorded with the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The energy dependence of the v1(y) slope, dv1/dy|y=0, for deuterons, where y is the rapidity, is extracted for semicentral collisions (10%-40% centrality) and compared with that of protons. While the v1(y) slopes of protons are generally negative for sNN>10GeV, those for deuterons are consistent with zero, a strong enhancement of the v1(y) slope of deuterons is seen at the lowest collision energy (the largest baryon density) at sNN=7.7GeV. In addition, we report the transverse momentum dependence of v1 for protons and deuterons. The experimental results are compared with transport and coalescence models.