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Preprints and Communications
 Here
you can find JINR preprints and communications in pdf format starting
from 1999.
File size is given in bytes in round brackets.
| 2018 |
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E11-2018-43 (178.602)
Török Cs.
Speedup of Interpolating Spline Construction
The article introduces an efficient sequential algorithm
for computing spline coefficients.
The aim is to decrease the computational time.
A reduced-size tridiagonal system of linear equations is constructed
based on a recently derived relation for the unknown coefficients
of uniform cubic splines of class C2 at the odd grid points.
The even coefficients are computed from an explicit formula.
Thanks to the half-size system and use of a simple formula,
the suggested new sequential algorithm needs less
division than the traditional one
and it results in a non-negligible computational speedup.
Finally, a general approach to dyadic reduction of the dimensionality
of tridiagonal linear systems is proposed in consequence of which the size
of the systems gradually shrinks to half, quarter, etc.
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E13-2018-37 (434.371)
Bielewicz M. et al.
MCORD — MPD Cosmic Ray Detector for NICA
The Multi-Purpose Detector (MPD) is a part of the Nuclotron-based Ion Collider
fAcility (NICA) located in Dubna, Russia. For full functionality, the MPD
needs an additional trigger system for off-beam calibration of MPD
subdetectors and for rejection of cosmic ray particles (mainly muons). The
system could also be useful for astrophysics observations of cosmic showers
initiated by high energy primary particles. The consortium NICA-PL composed
of several Polish scientific institutions has been formed to define goals
and basic assumptions for MPD Cosmic Ray Detector (MCORD). This article
describes the early stage design of the MCORD detector based on plastic
scintillators with silicon photomultiplier photodetectors for scintillation
readout and of the electronic system based on MicroTCA crate. Plans for simulations
of MCORD detector performance are also presented.
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E13-2018-30 (259.663)
Chirikov-Zorin I. et al.
Performance of Shashlyk Calorimeter Read Out by SiPMs with High Pixel Density
The matrix of 3 × 3 modules of the EM calorimeter ECAL0 (COMPASS II) read out
by MPPC S12572-010P SiPM with the pixel density of 104 mm-2 and an
area of 3 × 3 mm is studied in the range of electron energies 1–30 GeV. It is
observed that MPPC has additional response nonlinearity and a
significantly smaller dynamic range of output signals than expected. The
mechanism of the effect based on the influence of parasitic capacitance
between pixels on the pixel gain is proposed. The energy resolution of the
calorimeter is measured to be (σE/E) = (7,1%/√E)(1+0,06/E)⊕1,4%E0,25
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P13-2018-28 (1.160.652)
Pepelyshev Yu. N., Rogov A. D., Sidorkin S. F.
Optimization Study of the Accelerator-Driven Multiplying Pulsed Neutron Sources
The neutron source operating at the Frank Laboratory of Neutron Physics
of the Joint Institute for Nuclear Research (Dubna) on the base of the IBR-2M pulsed
reactor with the flux density of thermal neutrons ∼ 1013cm-2 · s-1 will
exhaust its resource and be shut down by 2034. It is proposed to consider the proton-driven
subcritical pulsed neutron source instead of the IBR-2M. At present, the world mostly uses the
nonmultiplying neutron sources based on the high-current proton accelerators, for example, SNS or ESS with a
beam power of 3 and 5 MW, respectively. We present the computational comparison of the various categories of the
high-current proton accelerator-driven pulsed neutron sources in order to select the most optimal solutions.
The one-zone booster with a tungsten target and the core with plutonium dioxide which can be a promising option is shown.
For such a source, it is possible to obtain an average thermal neutron flux density of more than 5.0 · 1014 cm-2 · s-1 at a
proton beam power of 0.1–0.2 MW.
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P10-2018-23 (549.125)
Kirilov A. S., Morkovnikov I. A.
About the Concept of the File Repositary for Istruments at the IBR-2 Pulsed Reactor
The work is devoted to the concept of a central repository of measurement data from the IBR-2
instruments at the FLNP, JINR. The concept takes into account the variety of structures and data file formats
on specific instruments, the users' wishes, and estimated amount of disk space required. The questions of the
service organization for the work with the data into the storage were considered, taking into account the existing
system of automatic measurements registration Journal.
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E13-2018-22 (622.408)
Korepanova N. V. et al.
Neutron Noise Analysis Using the Basic Element Method
The full range of noise energy pulses reaches ±22% under normal
conditions of operation of the IBR-2M reactor (JINR, Dubna). Therefore, slow changes in average power, caused,
for example, by the movement of regulatory bodies, “drown” in the noises. But in a number of cases,
it is these slow components of the pulse energy variation, the so-called basic signals (baseline),
that are of fundamental importance for justifying the conditions for safe operation of the reactor.
To determine the baseline in the noises of the IBR-2M the sixth order mean-square piecewise polynomial approximation (MSPPA-6)
was used for the detection of the baseline in the noises of IBR-2M. The algorithm MSPPA-6 depends on control
parameters α, β, M and K, the optimal values of which depend on the initial noise parameters.
The algorithm was applied to both the static and the dynamic state of the reactor in the range of an average power
of 30 kW – 2 MW. The average processing time of one point on a PC x86_64 Processor Intel Core i5-4570 Sandy Bridge machine,
3.20 GHz, was 0.05 ms, which allows using the MSPPA-6 algorithm in real time.
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P3-2018-20 (552.724)
Zakharov M. A. et al.
Numerical Simulation of the Experiment on Observing Non-Stationary Diffraction of UCNs on a Moving Lattice
A set of programs has been created for modeling the experiment to study UCN diffraction on a moving grating.
The problem of diffraction of neutrons on a lattice with parameters corresponding to the actual experiment was solved
numerically on the basis of the equations of the dynamic theory of diffraction. The process of measuring the diffraction
spectrum by a time-of-flight Fourier diffractometer was simulated by the Monte Carlo method. Systematic errors in the reconstruction
of the neutron energy spectrum by the inverse Fourier spectrometry method are investigated. The results of numerical calculations are
compared with experimental data.
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E1-2018-18 (763.504)
Suchopár M. et al. (on behalf of the Collaboration
“Energy and Transmutation of Radioactive Waste”)
Activation Measurement of Neutron Production and Transport in a Thick Lead
Target and a Uranium Blanket during 4 GeV Deuteron Irradiation
Several simple accelerator-driven system (ADS) setups were irradiated with
relativistic proton and deuteron beams in the last years at the Nuclotron
synchrotron site of the Joint Institute for Nuclear Research (JINR) in
Dubna, Russia. This paper is dedicated to a 4 GeV deuteron irradiation of a
setup called Energy plus Transmutation (E + T), consisting of a lead target,
natural uranium blanket, and polyethylene shielding. This paper represents
the finalization of data analysis and concludes systematics of the proton
and deuteron experiments carried out with the E + T setup. Activation
detectors served for monitoring of proton and deuteron beams and for
measurements of neutron field distribution in model ADS studies. Products of
reactions with thresholds up to 106 MeV as well as non-threshold reactions
were observed in the samples. The yields of the produced isotopes were
determined using the gamma-ray spectrometry and compared with Monte Carlo
simulations performed with the MCNPX transport code.
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P11-2018-17 (311.312)
Ayryan E. A., Malykh M. D., Sevastianov L. A.
Finite Differences Method and Integration of the Differential Equations in Finite Terms
We show that standard approaches to integration of the differential
equations in finite terms contain the reference to numerical methods of the last centuries.
Further we describe the class of the differential equations of the first order allowing
good differential schemes. This means that the calculation by such scheme can be continued after mobile singularities.
After necessary introduction we describe such one-to-one scheme for the Riccati equation and prove its property mentioned above.
In conclusion we present n-to-n schemes for 1st order differential equations as their natural generalization.
Here we prove that one-to-one schemes exist only for the Raccati equation and investigate conditions of existence of 2-to-2 schemes.
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E1-2018-11 (1.393.237)
Tokarev M. (on behalf of the STAR Collaboration)
Recent STAR Spin Results and Spin Measurements at RHIC
The STAR experiment provides measurements of single- and double-spin
asymmetries in longitudinally and transversely polarized p+p collisions at √ s = 200 and 510 GeV
to deepen our understanding of the proton spin structure and dynamics of parton interactions over a wide range of collision energy,
momentum and rapidity of the various produced probes. Polarized processes with W± production allow us to study the spin-flavor
structure of the proton. Recent results obtained by STAR on the double longitudinal asymmetry, ALL, of pion and
jet production at √ s = 200 and 510 GeV, the single longitudinal, AL, and transverse,
AN, asymmetry of W± production at √ s =510 GeV are overviewed.
STAR results on azimuthal single transverse asymmetry of pion in p↑ + (p, Au)- and jet + π± â p↑ + p collisions are discussed.
The proposed Forward Calorimeter System (FCS) and Forward Tracking System (FTS) upgrades at STAR would significantly
improve the capabilities of existing detectors for measurements of observables such as asymmetries of pion, jet, Drel–Yan pairs produced at forward rapidities.
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E3-2018-7 (250.576)
Granja C. et al.
Two Methods of Determination
of Parities of Low-Lying States
in 159Gd from Analysis of
γ-Ray Intensities from
158Gd(nres,γ)159Gd Reaction
Energy levels and transitions in 159Gd were studied
by means of radiative capture of resonance
neutrons in 12 isolated resonances of 158Gd.
The time-of-flight technique was used on an enriched
target at the IBR-30 reactor at JINR, Dubna.
A total of 80 primary gamma transitions were recorded,
and their absolute intensities were determined resulting
in the observation of 1/2± and 3/2± levels up to
2.4 MeV.
Parities of the found levels were recalculated using two methods:
the first method consists in analyzing of intensities averaging
in 12 resonances, and in the second method individual intensities
are analyzed. The second method is described for the first time.
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P11-2018-6 (746.926)
Akishin P. G., Sapozhnikov A. A.
The Integral Formulation of the Magnetostatic Problem for Magnetic System Modelling
We consider the application of the volume integral method to the magnetic system
calculations. The major stages of modelling process are discussed:
the discretization of initial equations, the description of the algorithm
for dividing the area into elements, the calculation of matrix elements for
discretization problem and the solution for the obtained system of non-linear
equations. The results of modelling of magnetic systems using the discussed method are presented and compared with calculations performed by other programs.
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P2-2018-4 (837.094)
Sinegovsky S. I., Sorokovikov M. N.
Prompt Atmospheric Neutrinos in the Quark-Gluon String Model
We calculate the prompt atmospheric neutrino flux in the energy
range 1–105 TeV arising from decays of the charmed particles. Cross sections
of the D-mesons and Λc-baryons production in pA- and πA-collisions
are calculated in the framework of the phenomenological quark-gluon string model,
free parameters of which were improved using measurement data of the LHC experiments.
Predicted prompt neutrino flux is compatible with the constraint obtained in IceCube experiment.
Also we compare our calculation with other predictions obtained for different charm production models.
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P15-2018-3 (4.377.077)
Didyk A. Yu. et al.
Synthesis of Solid-State Structures and Chemical Elements under Irradiation by Bremsstrahlung γ Rays with a Maximum Energy of 10 MeV in Condensed Deuterium at a Pressure of 2.2 kbar
A high-pressure chamber filled with deuterium (DHPC) under initial pressure 2.2
kbar was irradiated during 49 h by bremsstrahlung γ rays with a maximum energy of 10 MeV.
After irradiation, several particles with dimensions up to 1 mm fell out of the DHPC.
On the inner surfaces of the DHPC, newly formed solid micro-objects
were found in the form of crystalline and amorphous microparticles, filaments,
nodules and inclusions. Investigations of the elemental composition of the revealed structures,
carried out with the help of X-ray microprobe analysis, showed the presence of chemical
elements in them, which were absent in the reaction chamber prior to the onset of irradiation.
The following chemical elements were registered: 6C, 7N, 8O, 11Na, 12Mg,
13Al, 14Si, 15P, 16S, 17Cl, 19K, 20,
21Sc, 22Ti, 24Cr, 25Mn, 26Fe, 28Ni, 30Zn,
33As, à òàêæå îëîâî 50Sn è ñâèíåö 82Pb.
The experiment on the synthesis of chemical elements in deuterium confirms
the results of previous experiments performed with other gases: hydrogen, helium and xenon.
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2018-1 (14.227.816)
Brief Review of Topmost Scientific Results Obtained in 2017 at the Joint Institute for Nuclear Research
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