284 research outputs found
Multifragmentation in Collisions of 4.4gev-Deuterons with Gold Target
The relative velocity correlation function of pairs of intermediate mass
fragments has been studied for d+Au collitions at 4.4 GeV. Experimental
correlation functions are compared to that obtained by multibody Coulomb
trajectory calculations under the assumption of various decay timees of the
fragmenting system. The combined approach with the empirically modified
intranuclear cascade code followed by the statistical multifragmentation model
was used to generate the starting conditions for these calculations. The
fragment emossion time is found to be less than 40 fm/c.Comment: Accepted for publication in Bulletin of the Russian Academy of
Sciences. Physic
Condensation of a tetrahedra rigid-body libration mode in HoBaCo4O7 : the origin of phase transition at 355 K
Rietveld profiles, Moessbauer spectra and x-ray absorption fine structure
(XAFS) were analyzed through the structural phase transition at Ts = 355 K in
HoBaCo4O7. Excess of the oxygen content over O7 was avoided via annealing the
samples in argon flow at 600 degree C. Space groups (S.G.) Pbn21c and P63mc
were used to refine the structure parameters in the low- and high-temperature
phases, respectively. Additionally, the Cmc21 symmetry was considered as a
concurrent model of structure of the low-temperature phase. In the
high-temperature phase, severe anisotropy of thermal motion of the major part
of the oxygen atoms was observed. This anisotropic motion turns to be quenched
as the sample is cooled below Ts. The variation of quadrupole splitting near Ts
is not similar to a steplike anomaly frequently seen at the charge-ordering
transition. We observe instead a dip-like anomaly of the average quadrupole
splitting near Ts. Narrow distribution of the electric field gradient (EFG)
over different cobalt sites is observed and explained on the basis of
point-charge model. XAFS spectra show no evidence of significant difference
between YBaCo4O7 (T > Ts) and HoBaCo4O7 (T < Ts). The origin of the transition
at Ts is ascribed to the condensation of the libration phonon mode associated
with the rigid-body rotational movements of the starlike tetrahedral units, the
building blocks of kagome network. It is shown that the condensation of the
libration mode is not compatible with translation symmetry for the hexagonal
S.G., but compatible for the orthorhombic S.G. The orthorhombic lattice
parameters and EFG components (Vxx, Vyy, Vzz) vary smoothly with temperature at
approaching Ts and closely follow each other.Comment: 13 figure
Analysis of hadron production in nucleus-nucleus interactions up to and out of kinematical limit of free NN-collisions in the frame of FRITIOF model
In the framework of the modified FRITIOF model, the inclusive spectra of the
cumulative -, -mesons and protons produced in the
nucleus-nucleus interactions at 4.5 GeV/c/nucleon and 4.2 GeV/c/nucleon are
calculated. It is shown that the model reproduces qualitatively, and in some
cases quantitatively the main experimental regularities of -mesons
production, and "soft" part of the proton spectra. According to the model the
production of the cumulative particles is connected with the mechanism of the
"soft" nucleon-nucleon interaction.Comment: 12 pages, 11 figure
Total, ageand sex-specific mortality after discharge of patients with heart failure: the first large-scale cohort real-world study on Russian population
Aim. To assess total, ageand sex-specific survival rate after discharge of patients with heart failure (HF) using real-world electronic health data.Material and methods. This retrospective analysis of data from the St. Petersburg Chronic Heart Failure Registry was performed. Hospitalizations of patients aged 18 years with a diagnosis code I50.x (International Classification of Diseases, 10th revision) were included in the period from January 1, 2019 to December 31, 2023. Cases with acute myocardial infarction, cerebrovascular accident, coronavirus disease 2019, hospitalization duration of >30 days, and death during the current hospitalization were not included.Results. The study included 73450 patients aged 18 to 99 years (mean age, 73±12 years; women, 59,1%). During a median follow-up of 388 days, 16212 (22,1%) patients died. The cumulative death probability within one and five years after discharge was 16,3% and 48,9%. At each time period, the rate was higher in men when stratified by age and as age increased.The mortality rate was 15,3 (95% confidence interval 15,1 to 15,6) per 100 patientyears. For all subgroups, the highest value was recorded in the first month after discharge (50,1 per 100 patient-years), reaching a maximum in the subgroup of elderly and senile patients (60,7 per 100 patient-years).Conclusion. Within 1 year and 5 years after hospital discharge, 16,3% and 48,9% of patients with HF die, respectively. The highest death risk is typical in the first month after discharge, especially for elderly and senile patients
Search for CP-violating Neutrino Non-Standard Interactions with the NOvA Experiment
This Letter reports a search for charge-parity (CP) symmetry violating
non-standard interactions (NSI) of neutrinos with matter using the NOvA
Experiment, and examines their effects on the determination of the standard
oscillation parameters. Data from
and
oscillation
channels are used to measure the effect of the NSI parameters
and . With 90% C.L. the magnitudes of
the NSI couplings are constrained to be
and . A degeneracy at
is reported, and we observe that the
presence of NSI limits sensitivity to the standard CP phase
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