994 research outputs found
Elliptic flow of heavy-flavour decay electrons in Pb-Pb collision at = 2.76 TeV with ALICE
We present the elliptic flow of electrons from the semi-leptonic
decays of heavy-flavour hadrons at mid-rapidity for semi-central (
centrality) Pb-Pb collisions at = 2.76 TeV measured with
the ALICE detector. A positive is observed at low in
semi-central collisions. Comparisons with previous measurements obtained at
lower collision energy at RHIC in Au-Au collisions at =
0.2 TeV and with theoretical models are also presented.Comment: 3 pages, 4 figure
Measurements of heavy-flavour production and azimuthal anisotropy in Pb--Pb collisions with the ALICE detector
Hadrons containing heavy quarks, i.e. charm or beauty, are unique probes of
the properties of the hot and dense QCD medium produced in heavy-ion
collisions. Due to their large masses, heavy quarks are produced at the initial
stage of the collision, almost exclusively via hard partonic scattering
processes. Therefore, they are expected to experience the full collision
history propagating through the QCD medium losing energy via elastic and
inelastic collisions with the medium constituents. The ALICE collaboration has
measured the production of open heavy-flavour hadrons via their hadronic and
semi-electronic decays at mid-rapidity and in the semi-muonic decay channel at
\mbox{forward rapidity} in pp, p--Pb and Pb--Pb collisions. In this talk the
latest results on the open \mbox{heavy-flavour nuclear modification factor,
, and elliptic flow, , are presented}.Comment: LHCP 2014 Conferenc
Heavy flavors and quarkonia: highlights, open questions, and perspectives
An overview of the phenomenology and experimental results on open
heavy-flavour and quarkonium production in heavy-ion collisions at the RHIC and
at the LHC energies is presented, with special emphasis on observables that
carry information from the different collision stages. Perspective for future
measurements and phenomenological modeling, that will shed light on the current
open question in heavy-ion collisions, will be also discussed.Comment: 10 pages, 6 figures, Contribution to the proceedings of the 11th
International Conference on Hard and Electromagnetic Probes of High Energy
Nuclear Collisions (Hard Probes 2023
Momentum distribution of charm hadrons in a fluid-dynamic approach
Exploiting a mapping between transport theory and fluid dynamics, we show how
a fluid-dynamic description of the diffusion of charm quarks in the QCD plasma
is feasible. We show results for spectra of charmed hadrons obtained with a
fluid-dynamic description of the quark-gluon plasma (QGP) coupled with the
conservation of a heavy-quark - antiquark current. We compare our calculations
with the most recent experimental data in order to provide further constraints
on the transport coefficients of the QGP.Comment: Hard Probes 202
Fluid dynamics of charm quarks in the quark--gluon plasma
A fluid-dynamic approach to charm-quark diffusion in the quark-gluon plasma
(QGP) is developed for the first time. Results for integrated yields and
momentum distributions of charmed hadrons obtained with a fluid-dynamic
description for the dynamics of the QGP coupled to an additional
heavy-quark-antiquark current are shown. In addition to the thermodynamic
Equation of State (EoS), this description uses a heavy-quark diffusion constant
which we take from Lattice QCD calculations. The results describe
quantitatively experimental data measured at the LHC at the center-of-mass
energy of = 5.02 TeV up to 4-5 GeV/,
showing that charm quarks undergo a very fast hydrodynamization in the medium
created by ultrarelativistic heavy-ion collisions.Comment: 11 pages, 6 figure
Elucidating the multiplicity dependence of J/ψ production in proton–proton collisions with PYTHIA8
A study of prompt and non-prompt J/ψ production as a function of charged-particle multiplicity in inelastic proton–proton (pp) collisions at a centre-of-mass energy of s√ = 13 TeV based on calculations using the PYTHIA8 Monte Carlo is reported. Recent experimental data shows an intriguing stronger-than-linear increase of the self-normalized J/ψ yield with multiplicity; several models, based on initial or final state effects, have been able to describe the observed behaviour. In this paper, the microscopic reasons for this behaviour, like the role of multiple parton interactions, colour reconnections and auto-correlations are investigated. It is observed that the stronger-than-linear increase and the transverse momentum (pT) dependence, contrary to what is predicted by the other available models, can be attributed to auto-correlation effects only. In absence of auto-correlation effects, the increase of the yield of J/ψ with multiplicity – and in general for all hard processes – is weaker than linear for multiplicities exceeding about three times the mean multiplicity. The possibility of disentangling auto-correlation effects from other physical phenomena by measuring the charged-particle multiplicity in different pseudo-rapidity and azimuthal regions relative to the J/ψ direction is investigated. In this regard, it is suggested to extend the experimental measurements of J/ψ production as a function of the charged-particle multiplicity by determining the multiplicity in several azimuthal regions and in particular in the Transverse region with respect to the direction of the J/ψ meson
Розвиток ідеї європейської інтеграції та її значення для України
У статті аналізується сутність ідеї європейської інтеграції,
її еволюція протягом століть. Досліджуються теоретичні основи
формування та розвитку Європейського Союзу, обґрунтовується
необхідність євроінтеграційної стратегії України як ключового
пріоритету зовнішньої та внутрішньої політики нашої держави.The article analyses the essence of the idea of European integration,
its evolution during the centuries and researches the theoretical
foundations of the formation and development of the European Union,
proves the need for European integration strategy of Ukraine as a key
priority of foreign and internal policy
Функциональные особенности словообразовательных синонимов современного немецкого языка
Статья из специализированного выпуска научного журнала "Культура народов Причерноморья", материалы которого объединены общей темой "Язык и Мир" и посвящены общим вопросам Языкознания и приурочены к 80-летию со дня рождения Николая Александровича Рудякова.Стаття із спеціалізованого випуску наукового журналу "Культура народов Причерноморья", матеріали якого поєднані загальною темою "Мова і Світ" і присвячені загальним питанням мовознавства і приурочені до 80-річчя з дня народження Миколи Олександровича Рудякова
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