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1.
Eur Phys J A Hadron Nucl ; 59(10): 232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860634

RESUMO

The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γp→π0p and γp→ηp reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the ηn system at W=1.68GeV. A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S11(1535) and S11(1650) resonances within the S11-partial wave.

2.
Artigo em Russo | MEDLINE | ID: mdl-31465652

RESUMO

The article presents the analysis of disability on the cardiovascular diseases, according to the Bureau of Medical and Social Expertise in the Nizhny Novgorod region in dynamics for 2003-2013. The article analyzed the number of persons recognized as disabled according the Bureau of Medical and Social Expertise, calculated accumulated contingent disabled due to cardiovascular diseases according to the pension fund. The years of life lost due to disability in dynamics were calculated for 2004-2013 years.


Assuntos
Doenças Cardiovasculares/epidemiologia , Pessoas com Deficiência , Humanos , Federação Russa
3.
Phys Rev Lett ; 117(13): 132502, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27715117

RESUMO

The double polarization observable E and the helicity dependent cross sections σ_{1/2} and σ_{3/2} were measured for η photoproduction from quasifree protons and neutrons. The circularly polarized tagged photon beam of the A2 experiment at the Mainz MAMI accelerator was used in combination with a longitudinally polarized deuterated butanol target. The almost 4π detector setup of the Crystal Ball and TAPS is ideally suited to detect the recoil nucleons and the decay photons from η→2γ and η→3π^{0}. The results show that the narrow structure previously observed in η photoproduction from the neutron is only apparent in σ_{1/2} and hence, most likely related to a spin-1/2 amplitude. Nucleon resonances that contribute to this partial wave in η production are only N 1/2^{-} (S_{11}) and N 1/2^{+} (P_{11}). Furthermore, the extracted Legendre coefficients of the angular distributions for σ_{1/2} are in good agreement with recent reaction model predictions assuming a narrow resonance in the P_{11} wave as the origin of this structure.

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