1,315 research outputs found
Charged charmonium-like Z+(4430) from rescattering in conventional B decays
In a previous paper we suggested an explanation for the peak designated as
in the mass spectrum, observed by Belle in
decays, as an effect of
rescattering in the decays
, where the is
an as-yet unobserved radial excitation of the pseudoscalar ground state
-meson. In this paper, we demonstrate that this hypothesis
provides an explanation of the double -like peaking structures, which were
studied by LHCb with much higher statistics. While according to our hypothesis,
the origin of the peaking structures is purely kinematical, reflecting the
presence of a conventional resonance in the hidden intermediate state, the
amplitude of the peak carries a Breit-Wigner-like complex phase,
arising from the intermediate resonance. Thus, our
hypothesis is entirely consistent with the recent LHCb measurement of the
resonant-like amplitude behaviour of the . We perform a toy fit to
the LHCb data, which illustrates that our approach is also consistent with all
the observed structure in the LHCb spectrum. We
suggest a critical test of our hypothesis that can be performed experimentally.Comment: 6 pages, 5 figure
The decomposition of level-1 irreducible highest weight modules with respect to the level-0 actions of the quantum affine algebra
We decompose the level-1 irreducible highest weight modules of the quantum
affine algebra with respect to the level-0 --action defined in q-alg/9702024. The decomposition is
parameterized by the skew Young diagrams of the border strip type.Comment: 22 pages, AMSLaTe
Parents and Children: Way to Choice of Profession
It is reported the monograph “Parent assistance in professional self-determination of senior pupils” (2016), prepared by T. D. Zelenkina, E. Yu. Pryazhnikova and M. G. Sergeyeva, touches upon the problem of effective vocational guidance. The value of the edition is based on the fact that problems of choosing the profession do not lose its relevance. The views of the authors of the monograph on parental involvement in career choice of their children are characterized. For example, it is noted that the family may not only contribute to the process of professional self-determination, but also prevent correct choice. Model of training parents to help in professional self-determination of senior pupils proposed by the authors is briefly described
The Yangian of sl(n|m) and the universal R-matrix
In this paper we study Yangians of sl(n|m) superalgebras. We derive the
universal R-matrix and evaluate it on the fundamental representation obtaining
the standard Yang R-matrix with unitary dressing factors. For m=0, we directly
recover up to a CDD factor the well-known S-matrices for relativistic
integrable models with su(N) symmetry. Hence, the universal R-matrix found
provides an abstract plug-in formula, which leads to results obeying
fundamental physical constraints: crossing symmetry, unitrarity and the
Yang-Baxter equation. This implies that the Yangian double unifies all desired
symmetries into one algebraic structure. In particular, our analysis is valid
in the case of sl(n|n), where one has to extend the algebra by an additional
generator leading to the algebra gl(n|n). We find two-parameter families of
scalar factors in this case and provide a detailed study for gl(1|1).Comment: 24 pages, 2 figure
Level Statistics of XXZ Spin Chains with Discrete Symmetries: Analysis through Finite-size Effects
Level statistics is discussed for XXZ spin chains with discrete symmetries
for some values of the next-nearest-neighbor (NNN) coupling parameter. We show
how the level statistics of the finite-size systems depends on the NNN coupling
and the XXZ anisotropy, which should reflect competition among quantum chaos,
integrability and finite-size effects. Here discrete symmetries play a central
role in our analysis. Evaluating the level-spacing distribution, the spectral
rigidity and the number variance, we confirm the correspondence between
non-integrability and Wigner behavior in the spectrum. We also show that
non-Wigner behavior appears due to mixed symmetries and finite-size effects in
some nonintegrable cases.Comment: 19 pages, 6 figure
Steel surface TiCrN, TiMoNcoatings structural phase state change features after low-energy alpha particles irradiation
The low-energy alpha particles irradiation impact on structural phase composition and 321S31 steel surface TiCrN and TiMoN coatings morphology have been summarized. The samples irradiation has been carried out in the DTs-60 (the Dubna cyclotron) heavy-ion accelerator by the{4}He{+2} low-energy ions (40 keV) into a 1.0•10{17} ion/cm{2} fluence. It has been established thatthe 321S31 steel alpha particles implantation having energy of 40 keV results in the austenite initial γ-structurepartial transfer, stimulated by the irradiation, to the martensiteα-structure. The low-energy alpha particles irradiation within the fluencies range from 10{16} to 10{17} ion/cm{2} for the TiCrN and TiMoN coatings formed by the ionic bombardment condensation method doesn't result in the phase transfers with a coating crystal lattice type change
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