486 research outputs found
Coherent production on nuclei and measurements of total cross sections for unstable particles
The Kölbig–Margolis formula is fitted to some explicitly nonperturbative models of diffractive production. It is shown that, in spite of the fact that the standard procedure of fitting the integrated cross sections may give acceptable fits, thus obtained "cross sections of unstable particles", , grossly disagree with the "true" cross sections known exactly from the models
Spatial distribution and reduction of PCDD/PCDF Toxic Equivalents along three shallow lowland reservoirs
Reservoirs situated along a river continuum are
ecosystems where rates of transfer of suspended matter and
associated micropollutants are reduced due to sedimentation,
accumulation, and biological and physical transformation processes.
Among the micropollutants, PCDDs and PCDFs are
substances that are highly toxic and carcinogenic for humans
and animals. They are emitted and dispersed in the environment
throughout the whole catchment area and may accumulate
in aquatic and terrestrial food chains, creating a risk for
human health. A wealth of data exists indicating the increase
in the concentrations of pollutants along a river continuum. A
comparative analysis of total, individual, and TEQ
PCDD/PCDF concentrations in large lowland, shallow reservoirs
located in different catchments (“I”—industrial/urban/
agricultural, “U”—urban/agricultural, and “A”—agricultural/
rural) showed decreases of the TEQ concentrations in bottom
sediments along a gradient from the middle sections to the
dam walls. Moreover, penta-, hexa-, and heptachlorinated
CDD/CDF congeners were reduced from 28.8 up to 93.6 %
in all three types of reservoirs. A further analysis of water samples from the inlets and outlets of the “A” reservoir
confirmed this tendency.The authors wish to express their sincere appreciation
to Prof. Konrad Rydzyński from the Nofer Institute of Occupational
Medicine in Lodz, Prof. Richard Robarts from the UNEP Global Environment Monitoring System (GEMS)/Water Programme, Prof. Paul
DuBowy from the U.S. Army Corps of Engineers, and Prof. David
Harper from the Department of Biology, the University of Leicester for
their constructive comments on an earlier version of this paper. The
authors also wish to acknowledge the research team of the Nofer Institute
of Occupational Medicine in Lodz: Dr Danuta Ligocka and Dr Wiktor
Wesołowski for their assistance during the laboratory processes.
The research was supported by the following projects of the Polish
Ministry of Science and Higher Education:
– N N305 365738 “Analysis of point sources pollution of nutrients,
dioxins and dioxin-like compounds in the Pilica River catchment and
draw up of reclamation methods”;
– 2PO4 G08830 “Accumulation of dioxins and dioxin-like pollutants
in the food chain of the Sulejowski and Włocławski Reservoirs: chemometric
analysis and toxicological estimation”
Tell Me How You Feel: Designing Emotion-Aware Voicebots to Ease Pandemic Anxiety In Aging Citizens
The feeling of anxiety and loneliness among aging population has been
recently amplified by the COVID-19 related lockdowns. Emotion-aware multimodal
bot application combining voice and visual interface was developed to address
the problem in the group of older citizens. The application is novel as it
combines three main modules: information, emotion selection and psychological
intervention, with the aim of improving human well-being. The preliminary study
with target group confirmed that multimodality improves usability and that the
information module is essential for participating in a psychological
intervention. The solution is universal and can also be applied to areas not
directly related to COVID-19 pandemic.Comment: 16 page
Determination of the total width of the eta' meson
Taking advantage of both the low-emittance proton-beam of the Cooler
Synchrotron COSY and the high momentum precision of the COSY-11 detector
system, the mass distribution of the eta' meson was measured with a resolution
of 0.33 MeV/c^2 (FWHM), improving the experimental mass resolution by almost an
order of magnitude with respect to previous results. Based on the sample of
more than 2300 reconstructed pp --> pp eta' events the total width of the eta'
meson was determined to be 0.226 +- 0.017(stat.) +- 0.014(syst.) MeV/c^2.Comment: 4 pages, 4 figure
Measurement of the invariant mass distributions for the pp -> ppeta' reaction at excess energy of Q = 16.4 MeV
The proton-proton and proton-eta' invariant mass distributions have been
determined for the pp -> ppeta' reaction at an excess energy of Q = 16.4 MeV.
The measurement was carried out using the COSY-11 detector setup and the proton
beam of the cooler synchrotron COSY. The shapes of the determined invariant
mass distributions are similar to those of the pp -> ppeta reaction and reveal
an enhancement for large relative proton-proton momenta. This result, together
with the fact that the proton-eta interaction is much stronger that the
proton-eta' interaction, excludes the hypothesis that the observed enhancement
is caused by the interaction between the proton and the meson
System Response Kernel Calculation for List-mode Reconstruction in Strip PET Detector
Reconstruction of the image in Positron Emission Tomographs (PET) requires
the knowledge of the system response kernel which describes the contribution of
each pixel (voxel) to each tube of response (TOR). This is especially important
in list-mode reconstruction systems, where an efficient analytical
approximation of such function is required. In this contribution, we present a
derivation of the system response kernel for a novel 2D strip PET.Comment: 10 pages, 2 figures; Presented at Symposium on applied nuclear
physics and innovative technologies, Cracow, 03-06 June 201
Isospin dependence of the eta prime meson production in nucleon-nucleon collisions
A comparison of the close-to-threshold total cross section for the eta prime
production in pp --> pp eta prime and pn --> pn eta prime reactions constitutes
a tool to investigate the eta prime meson structure and the reaction mechanism
in the channels of isospin I=0 and I=1 and may provide insight into the
flavour-singlet (perhaps also into gluonium) content of the eta prime meson. In
this contribution we present preliminary results of measurement of the
quasi-free production of the eta prime meson in the proton-neutron collisions
conducted using the COSY-11 facility.Comment: Presented at 10th International Workshop on Meson Production,
Properties and Interaction (MESON 2008), Cracow, Poland, 6 - 10 June 200
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