In this paper, we analyze the correlations between the mean transverse momentum and the multiplicity of charged particles in proton–proton collisions using four different models: EPOS, SMASH, PHSD ...and UrQMD. Three strongly intensive quantities, as well as second- and third-order cumulants of transverse momentum, were chosen as variables for the resaerch. In the dependences of strongly intensive quantities on energy, discrepancies between the models were found. In the model SMASH, both for strongly intensive quantities and for cumulants, a certain ‘‘wave’’ arise, which can become evidence of a transition from the resonance regime to strings. Such a nontrivial behavior of
correlations in
collisions as ‘‘baseline’’ may later cause difficulties in explaining the results for
collisions. All models coincide with the prediction of the hydrodynamic model. Experimental results obtained at MPD/NICA can clarify this model analysis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The soil microbiome was investigated at environmentally distinct locations on King George Island in the South Shetland Islands (Antarctic Peninsula) using 16 S rRNA gene pyrosequencing. The taxonomic ...composition of the soil prokaryotes (bacteria and archaea) was evaluated at three sites representing human-disturbed soils (Bellingshausen Station) and soils undergoing different stages of deglaciation (fresh and old moraines located near Ecology Glacier). The taxonomic analysis revealed 20 bacterial and archaeal phyla, among which Proteobacteria (29.6%), Actinobacteria (25.3%), Bacteroidetes (15.8%), Cyanobacteria (11.2%), Acidobacteria (4.9%) and Verrucomicrobia (4.5%) comprised most of the microbiome. In a beta-diversity analysis, the samples formed separate clusters. The Bellingshausen Station samples were characterized by an increased amount of Nostoc sp. and Janibacter sp. Although the deglaciation history had less of an effect on the soil microbiome, the early stages of deglaciation (Sample 1) had a higher proportion of bacteria belonging to the families Xanthomonadaceae, Sphingomonadaceae and Nocardioidaceae, whereas the older moraines (Sample 2) were enriched with Chthoniobacteriacae and N1423WL. Solirubrobacteriales, Gaiellaceae and Chitinophagaceae bacteria were present in both stages of deglaciation, characterized by genus-level differences. Taxonomic analysis of the abundant operational taxonomic units (OTUs) revealed both endemic (Marisediminicola antarctica, Hymenobacter glaciei) and cosmopolitan bacterial species in the microbiomes.
Th
e
paper presents results on multiplicity correlations in two rapidity intervals and mean transverse momentum vs event multiplicity correlation function calculated in the developed Monte-Carlo ...model of multi-particle production run for
p
+
p
interactions at
and
GeV. The model is based on interacting colour strings approach with longitudinal and transverse strings dynamics. Results are compared with the ALICE data and PYTHIA 8.3 simulations.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We study the initial states of p+p interactions and their influence on the correlation and fluctuation observables that are sensitive to them by considering the processes of multipomeron exchange and ...stretching of color QCD strings. We discuss the full string dynamics, their longitudinal motion due to the deceleration of the string ends, and the transverse motion caused by attraction due to the exchange of sigma mesons with subsequent fusion. We calculate the coefficient of rapidity correlations and the strongly intensive variables constructed for the multiplicity of charged particles,
, and the total transverse momentum
for inelastic p+p interactions at the energy of
GeV.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The paper studies the possibility to correct strongly intensive quantities ΔPT, N, £PT, N, and £NF, NB for detector inefficiencies by means of RooUnfold package. Several tests of applying Unfolding ...technique to 1D- and 2D-dimensional distributions were done on Monte-Carlo generated data in NA61/SHINE acceptance. Results reveal that several aspects of this analysis have to be improved.
We calculate the strongly intensive variables Σ and Δ that suppress trivial volume fluctuations and are constructed for the charged particle multiplicity n and the total transverse momentum
P
t
in a ...modified multipomeron exchange approach for proton-proton interactions in the range of collision energies attainable with the SPS and LHC accelerators. In this approach, the interaction between the color quark-gluon strings formed from cut pomerons are effectively taken into account; in this case, the role of these interactions increases as the collision energy increases. The inequalities Σ(
P
t
,
n
) > 1 and Δ(
P
t
,
n
) < 1, which agree with the experimental data, are the main result of the calculations for energies attainable at the SPS. We show that as the energy increases, Σ(
P
t
,
n
) behaves nonmonotonically and Δ(
P
t
,
n
) increases.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Soil microbiome makes a significant contribution to the implementation of ecosystem services, which are necessary for the sustainable functioning of ecosystems. Soils of central Yakutia develop under ...dynamic physical and chemical conditions (long-term freezing/thawing processes, redistribution of nutrients), which ensures the formation of a specific microbial community in natural and anthropogenically transformed areas. The object of the study was the natural, fallow, and agricultural soils of central Yakutia. The method of high-throughput sequencing of 16S rRNA gene fragment on Illumina MiSEQ sequencer was used to analyze the microbial community. As a result, in fallow lands a decrease in nutrients was revealed if compared to the lands involved in agricultural turnover. Based on the composition of the microbiome it was observed that the most common phyla are Acidobacteria, Actinobacteria, Verrucomicrobiota, Pseudomonadota (Alphaproteobacteria, Gammaproteobacteria), Bacterioidota, Chloroflexi, Planctomycetota. The presence of a core set of microorganisms for the studied soils was recorded, up to 17.8% of phylotypes are unique and up to 25.7% are common to fallow lands and background plots. Microbial communities vary depending on geographical locations and on types of natural resource use. The most distinct microbial communities are formed in hydromorphic soils with the development of gley processes, as well as in agricultural soils.
Strongly intensive quantities for multiplicity and total transverse momentum are calculated using the multipomeron exchange approach for
pp
collisions in the range of SPS to LHC energies. The model ...allows for the interaction between quark–gluon strings, the role of which grows along with the energy of collisions. This approach is generalized to the case of
p
Pb collisions.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Multiparticle production in soft hadronic interactions can be successfully described in the framework of the color-string approach, which will probably be derived from the first principles of ...chromodynamics in the future. A fundamental property of this approach is the translation invariance of the rapidity spectrum of charged particles produced by one source at high energies. This symmetry results in the appearance of long-range rapidity correlations through event-by-event fluctuations of the number and/or type of strings. We describe the behavior of correlations between multiplicities (
n–n
) and between the transverse momentum and multiplicities (
pt–n
) of charged particles with the mechanism of forming sources of two types taken into account. We obtain an exact analytic expression for the (
n–n
)-correlation coefficient. Because no exact solution can be obtained for the (
pt–n
)-correlation coefficient, we propose an effective approximation that significantly simplifies numerical computations. We verify all these results by direct simulation using the Monte Carlo method. We also investigate how the fusion mechanism influences the behavior of strongly intensive variables characterizing the multiplicity fluctuations in two rapidity windows.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Objectives.
The reduction of the anthropogenic burden on the environment is generally associated with the transition to alternative energy sources. However, some of these have only regional ...significance, while the effectiveness of others remains doubtful. On this point, innovative processes aimed at increasing the depth of oil refining may be equally important for reducing the carbon footprint. Wave-based technologies such as cavitation may also be included in these processes. Among the various methods for inducing such cavitation phenomena in oil refining, hydrodynamic approaches are especially promising. It has been shown that the treatment effectiveness increases with greater pressure or when augmenting the number of cavitation processing cycles. The aim of this work is to identify the factor (i.e., pressure gradient or number of treatment cycles) having the greatest influence on the change of the characteristics of the oil product.
Methods.
Cavitation phenomena were created by pumping dark oil products through a diffuser. The pressure gradient ranged from 20 to 50 MPa, while the number of cavitation processing cycles varied from 1 to 10. The influence of cavitation conditions on the change of fractional composition of petroleum products was analyzed. Target fractions are those having a boiling point up to 400°C.
Results.
It is shown that increased pressure generated in the diffuser leads to a linear increase in the yield of desired cuts. The dependence of the yield of these fractions on the number of processing cycles is described by the growth model with saturation. A proposed equation describes the influence of pressure and number of cycles on the yield of the fractions from initial boiling point temperature (T
IBP
) to 400°C following cavitation processing of dark oil products. Some of the coefficients of this equation have been associated with the physicochemical characteristics of the feedstock.
Conclusions.
An equation for predicting the maximum possible yield of the T
JBP
-400°C fraction as a result of cavitation processing under different conditions of the process is proposed according to the physicochemical characteristics of the feedstock. The prediction error did not exceed 12%. The equation analysis and comparison of energy consumption between different process regimes shows that a higher yield of the target product is achieved by increasing pressure gradient rather than the number of processing cycles.