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Ya. I. Azimov

Publications and source records attributed to Ya. I. Azimov.

28 records · Page 2Linked to original sources
arXiv2004

Nonstrange and other unitarity partners of the exotic Theta+ baryon

Given presently known empirical information about the exotic Theta+ baryon, we analyze possible properties of its SU(3)F partners, paying special attention to the nonstrange member of the antidecuplet N*. The modified PWA analysis presents two candidate masses, 1680 MeV and 1730 MeV. In both cases the N* should be highly inelastic. The theoretical analysis, based on the soliton picture and assumption of Gamma(Theta+) < 5 MeV, shows that most probably Gamma(N*) < 30 MeV. Similar analysis for Xi3/2 predicts its width to be not more than about 10 MeV. Our results suggest several directions for experimental studies that may clarify properties of the antidecuplet baryons, and structure of their mixing with other baryons.

nucl-th↗
arXiv2003

Light Baryon Resonances: Restrictions and Perspectives

The problem of nucleon resonances N' with masses below the Delta is considered. We derive bounds for the properties of such states. Some of these are new, while others improve upon existing limits. We discuss the nature of N' states, and their unitary partners, assuming their existence can be verified.

nucl-th↗
arXiv2003

Isospin violation in mixing and decays of rho- and omega-mesons

Influence of the isospin-violating (ρ^0, ω)-mixing is discussed for any pair of decays of ρ^0, ωinto the same final state. It is demonstrated, in analogy to the CP-violation in neutral kaon decays, that isospin violation can manifest itself in various forms: direct violation in amplitudes and/or violation due to mixing. In addition to the known decays (ρ^0, ω)\toπ^+π^- and (ρ^0, ω)\toπ^0γ, the pair of decays to e^+e^- and the whole set of radiative decays with participation of ρ^0, ω(in initial or final states) are shown to be also useful and perspective for studies. Existing data on these decays agree with the universal character of the mixing parameter and indirectly support enhancement of ρ^0\toπ^0γin respect to ρ^{\pm}\toπ^{\pm}γ. Future precise measurements will allow to separate different forms of isospin violation and elucidate their mechanisms.

hep-ph↗
arXiv2002

Mixing and decays of rho- and omega-mesons

Isospin violating mixing of ρ- and ω-mesons is reconsidered in terms of propagators. Its influence on various pairs of (ρ^0,ω)-decays to the same final states is demonstrated. Some of them, (ρ^0,ω)\toπ^+π^- and (ρ^0,ω)\toπ^0γ, have been earlier discussed in the literature, others (e.g., (ρ^0,ω)\toηγand (ρ^0,ω)\to e^+e^-) are new in this context. Changes in partial widths for all the decay pairs are shown to be correlated. The set of present experimental data, though yet inconclusive, provides some limits for the direct (ρω)-coupling and indirectly supports enhancement of ρ^0\toπ^0γin comparison with ρ^{\pm}\toπ^{\pm}γ, though not so large as in some previous estimates.

hep-ph↗
arXiv2000

Neutral kaons as decay products and analyzers of heavier flavors

Cascade decays of heavy flavor hadrons to states with neutral kaons are discussed as an instrument for detailed studies of the heavy hadron properties. For neutral flavored mesons the well-known kaon oscillations provide a unique experimental possibility of relating lighter/heavier eigenstate masses to (approximate) even/odd eigenstate CP-parities and to longer/shorter eigenstate lifetimes. As a result, they allow to eliminate sign ambiguities of CP-violating parameters and, therefore, to check the Standard Model (or to find New Physics). Specifically for charmed hadrons, both neutral/charged mesons and baryons, the secondary kaon oscillations permit unambiguous separation of Cabibbo-allowed and doubly-suppressed decay amplitudes, including measurement of their relative phases. For neutral $D$-meson decays the kaon oscillations can also discriminate, again unambiguously, between effects of $D$-meson mixing and interference of suppressed/allowed amplitudes. Another problem discussed is the influence of kaon CP-violation on the amplitude structure and on phenomenology of CP-violation in heavy hadron decays.

hep-ph↗
arXiv1999

Neutral kaons as instrument for studying heavier flavors

Strangeness oscillations in decays of neutral kaons are suggested to be used as an analyzer to investigate detailed properties of heavy flavor hadrons and their decays. Here we briefly explain why, where, and to what problems this approach may be applied.

hep-ph↗
arXiv1997

The Aharonov-Casher Effect for Particles of Arbitrary Spin

The Aharonov-Casher (AC) effect for quantum motion of a neutral magnetized particle in the electric field is believed to be a topological effect closely related to the known Aharonov-Bohm (AB) effect. We study how it depends on the spin of the particle involved. Duality of the AB and AC effects is demonstrated to exist only for two extreme spin (and magnetic moment) projections. Classical consideration confirms the conclusion. Motion of a classical magnetized particle with generally oriented magnetic moment in the AC field appears to be subjected to both forces and torques. Only for two special orientations of the magnetic moment (same as in the quantum case) the motion is effectively free and similar to the AB motion of a charged particle. Thus, the AC effect is not really topological. Presence of higher multipoles totally destroys the possible AB-AC duality.

hep-ph↗
arXiv1997

(Semi)classical motion in fields of Aharonov-Bohm and Aharonov-Casher

Particle motion in the fields of Aharonov-Bohm and Aharonov-Casher is considered in framework of the classical theory to reveal conditions admitting duality of the two configurations. Important role of orientation of the magnetic dipole moment is demonstrated. Duality becomes totally destroyed by addition of electric dipole and/or higher multipole moments. Correspondence between quantum and classical considerations is also discussed.

hep-ph↗
arXiv1995

Neutral Kaons without Weisskopf-Wigner Approximation

The model-independent formalism is constructed to describe decays of mixed particles without using the Weisskopf-Wigner approximation. Limitations due to various symmetries are traced for neutral $K-$mesons. As an application we show that effects of $CPT-$violation and going beyond WWA may be separated and studied independently.

hep-ph↗