657 research outputs found
New method for measuring longitudinal fuctuations and directed flow in ultrarelativistic heavy ion reactions
It has been shown in recent ALICE@LHC measurements that the odd flow
harmonics, in particular a directed flow, v1, occurred to be weak and dominated
by random fluctuations. In this work we propose a new method, which makes the
measurements more sensitive to the flow patterns showing global collective
symmetries. We demonstrate how the longitudinal center of mass rapidity
fluctuations can be identified, and then the collective flow analysis can be
performed in the event-by-event center of mass frame. Such a method can be very
effective in separating the flow patterns originating from random fluctuations,
and the flow patterns originating from the global symmetry of the initial
state.Comment: 8 pages, 2 figure
HYDRO + JETS (HYDJET++) event generator for Pb+Pb collisions at LHC
The Monte Carlo event generator HYDJET++ is one of the few generators,
designed for the calculations of heavy-ion collisions at ultrarelativistic
energies, which combine treatment of soft hydro-like processes with the
description of jets traversing the hot and dense partonic medium. The model is
employed to study the azimuthal anisotropy phenomena, dihadron angular
correlations and event-by-event (EbyE) fluctuations of the anisotropic flow in
Pb+Pb collisions at TeV. The interplay of soft and hard
processes describes the violation of the mass hierarchy of meson and baryon
elliptic and triangular flows at p_T > 2 GeV/c, the fall-off of the flow
harmonics at intermediate transverse momenta, and the worsening of the
number-of-constituent-quark (NCQ) scaling of elliptic/triangular flow at LHC
compared to RHIC energies. The cross-talk of v_2 and v_3 leads to emergence of
higher order harmonics in the model and to appearance of the ridge structure in
dihadron angular correlations in a broad pseudorapidity range. HYDJET++
possesses also the dynamical EbyE fluctuations of the anisotropic flow. The
model results agree well with the experimental data.Comment: 8 pages, 6 figures, contribution to Proceedings of the Winter
Workshop on Nuclear Dynamics 201
Comparative efficacy of medication and cardiac resynchronization therapy in patients with heart failure with reduced ejection fraction
Aim. To compare the effectiveness of standard conservative therapy for heart failure (HF) with the inclusion of sacubitril/valsartan combination and device therapy.Material and methods. The study included 64 patients from 38 to 73 years old (45 men and 19 women; mean age, 59,5±0,9 years) hospitalized in Baku (Azerbaijan) hospital due to NYHA class II-IV HF. The patients were divided into the experimental (group 1) and control (group 2) groups. The experimental group included 33 patients who took sacubitril/valsartan twice a day in combination with other drugs for standard HF therapy. The control group included 31 patients after cardiac resynchronization therapy. We compared clinical and hemodynamic parameters (including 6-minute walk test and echocardiography data) before and 6 months after treatment, as well as blood concentration of brain natriuretic peptide (BNP). In addition, Kaplan-Meier survival curves were analyzed.Results. As a result of 6-month therapy, clinical condition of patients in both groups was improved. In the experimental group, some parameters were significantly better than in the control one. So, the differences regarded distance in 6-minute walk test (pu=0,002), changes in HF class (pu=0,017), LV ESD (pu=0,006), LV EDD (pu=0,001) and blood BNP concentrations (pu<0,001).Conclusion. The use of sacubitril/valsartan combination as part of standard HF therapy was accompanied by a significant improvement in the clinical, hemodynamic and biochemical parameters of patients with HF compared with device therapy
Influence of resonance decays on triangular flow in heavy-ion collisions
Anisotropic flow in relativistic collisions of heavy-ions yields important information about the state of the hot and dense matter created in the collision. Study of triangular flow in Pb+Pb collisions at LHC was performed using HYDJET++ Monte Carlo generator. HYDJET++ combines both hydrodynamics-driven soft part together with hard jet-part, giving a realistic prediction for vast number of hadron species. The model also enables study of influence of final-state interactions on flow of created hadrons. Triangular flow patterns of pions, kaons and protons were studied. We found that resonance decays influence significantly the shape of the distributions
Higher harmonics of azimuthal anisotropy in relativistic heavy ion collisions in HYDJET++ model
The LHC data on azimuthal anisotropy harmonics from PbPb collisions at
center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted in
the framework of the HYDJET++ model. The cross-talk of elliptic and
triangular flow in the model generates both even and odd harmonics of
higher order. Comparison with the experimental data shows that this mechanism
is able to reproduce the and centrality dependencies of
quadrangular flow , and also the basic trends for pentagonal and
hexagonal flows.Comment: 12 pages including 13 figures as EPS-files; prepared using LaTeX
package for publication in the European Physical Journal
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