Results for "N. Grittini"

total 74676took 0.13s
On zeros of irreducible characters lying in a normal subgroupFeb 08 2019Jul 28 2019Let $N$ be a normal subgroup of a finite group $G$. In this paper, we consider the elements $g$ of $N$ such that $\chi(g)\neq 0$ for all irreducible characters $\chi$ of $G$. Such an element is said to be non-vanishing in $G$. Let $p$ be a prime. If all ... More
Zeros of irreducible characters lying in a normal subgroupFeb 08 2019Let $N$ be a normal subgroup of a finite group $G$. An element $g\in G$ such that $\chi(g)=0$ for some irreducible character $\chi$ of $G$ is called a vanishing element of $G$. The aim of this paper is to analyse the influence of the $\pi$-elements in ... More
On zeros of irreducible characters lying in a normal subgroupFeb 08 2019Feb 13 2019Let $N$ be a normal subgroup of a finite group $G$. An element $g\in G$ such that $\chi(g)=0$ for some irreducible character $\chi$ of $G$ is called a vanishing element of $G$. The aim of this paper is to analyse the influence of the $\pi$-elements in ... More
Bosonic stimulation of cold 1s excitons into a harmonic potential minimum in Cu$_2$OFeb 07 2003Density distribution of cold exciton clouds generated into a strain-induced potential well by two-photon excitation in Cu$_2$O is studied at 2 K. We find that an anomalous spike, which can be interpreted as accumulation of the excitons into the ground ... More
The Universal Equation of State near the Critical Point of QCDJan 12 2004Jun 18 2004We study the universal properties of the phase diagram of QCD near the critical point using the exact renormalization group. For two-flavour QCD and zero quark masses we derive the universal equation of state in the vicinity of the tricritical point. ... More
Analytical Estimate of the Effect of Spherical Inhomogeneities on Luminosity Distance and RedshiftFeb 06 2008Jun 25 2008We provide an analytical estimate of the effect of a spherical inhomogeneity on light beams that travel through it. We model the interior of the inhomogeneity in terms of the Lemaitre-Tolman-Bondi metric. We assume that the beam source is located outside ... More
Heavy quark skyrmionsMay 18 2009The description of the heavy baryons as heavy-meson--soliton bound systems is reviewed. We outline how such bound systems arise from effective lagrangians that respect both chiral symmetry and heavy quark symmetry. Effects due to finite heavy quark masses ... More
Wind of presupernova IIn SN~1997egJan 15 2019Spectra and phototometry of type IIn supernova SN 1997eg are used to determine properties of the circumstellar gas lost by the presupernova during the latest 200 years before the explosion. The analysis of narrow H$\alpha$ and [Fe X] 6374 \AA\ results ... More
Connection between Diffraction and Small-$x$Nov 30 2001A brief review of the modern QCD theory of diffractive DIS is given.
Diffractive DIS: Where Are We?Nov 12 2001Nov 20 2001A brief review of the modern QCD theory of diffractive DIS is given. The recent progress has been remarkably rapid, all the principal predictions from the color dipole approach to diffraction - the $(Q^2+m_V^2)$ scaling, the pattern of SCHNC, shrinkage ... More
Diffractive Vector Mesons in DIS: Meson Structure and QCDSep 15 2000I review the modern status of QCD theory of diffractive vector meson production with the focus on shrinkage of photons with Q2 and (Q2+mV2)$scaling, j-plane properties of the QCD pomeron and Regge shrinkage of diffraction cone, $s$-channel helicity non-conservation ... More
Spin dependence of diffractive DISMay 31 1999I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS including the unitarity driven demise of the Burkhardt-Cottingham sum rule and strong scaling departure from the Wandzura-Wilczek relation. ... More
New upper bound for a class of vertex Folkman numbersJan 11 2006We improve the previuosly known bound for some vertex Folkman numbers.
Upgrading the Local Ergodic Theorem for planar semi-dispersing billiardsMay 29 2007Jun 04 2009The Local Ergodic Theorem (also known as the `Fundamental Theorem') gives sufficient conditions under which a phase point has an open neighborhood that belongs (mod 0) to one ergodic component. This theorem is a key ingredient of many proofs of ergodicity ... More
Radiative decays of phi-meson about nature of light scalar resonancesSep 11 2003We show on gauge invariance grounds that the fine threshold phenomenon is discovered in the radiative decays phi->gamma a0->gamma pi0 eta and phi->gamma f0->gamma pi0pi0. This enables to conclude that production of the lightest scalar mesons a0(980) and ... More
Nature of the scalar $a_0(980)$ and $f_0(980)$-mesonsMar 10 1998Oct 28 1998It is presented a critical consideration of all unusual properties of the scalar $a_0(980)$ and $f_0(980)$-mesons in the four-quark, two-quark and molecular models. The arguments are adduced that the four-quark model is more preferable. It is discussed ... More
Production of pseudovector heavy quarkonia by virtual Z boson in electron-positron collisionsApr 03 1996Apr 09 1996It is shown that $BR(\chi_{b1}(1P)\rightarrow Z\rightarrow e^+e^-)\simeq 3.3\cdot 10^{-7}$, $BR(\chi_{b1}(2P)\rightarrow Z\rightarrow e^+e^-)\simeq 4.1\cdot 10^{-7}$ and $BR(\chi_{c1}(1P)\rightarrow Z\rightarrow e^+e^-)\simeq 10^{-8}$ that give a good ... More
Flow-invariant hypersurfaces in semi-dispersing billiardsMar 15 2006This work results from our attempts to solve Boltzmann-Sinai's hypothesis about the ergodicity of hard ball gases. A crucial element in the studies of the dynamics of hard balls is the analysis of special hypersurfaces in the phase space consisting of ... More
On diameter bounds for planar integral point sets in semi-general positionJul 22 2019A point set $M$ in the Euclidean plane is called a planar integral point set if all the distances between the elements of $M$ are integers, and $M$ is not situated on a straight line. A planar integral point set is called to be in semi-general position, ... More
SN 2011ht: Weak explosion in massive extended envelopeOct 21 2015Oct 29 2015A possibility is explored to account for the light curve and the low expansion velocity of the supernova SN~2011ht, a member of group of three objects showing signatures of both IIn and IIP supernovae. It is argued that the radiated energy and the expansion ... More
Affine metrics and algebroid structures: Application to general relativity and unificationAug 14 2011Affine metrics and its associated algebroid bundle are developed. Theses structures are applied to the general relativity and provide an structure for unification of gravity and electromagnetism. The final result is a field equation on the associated ... More
$ΔS = 1$ Hadronic Weak Decays of Hyperons in a Soliton ModelSep 23 1997We study the parity violating hyperon non-leptonic weak decays in the three flavor Skyrme model. We follow the approach in which the symmetry breaking terms in the action are diagonalized exactly within the collective coordinate approximation. We show ... More
Fate of k_perp-factorization for hard processes in nuclear environmentDec 15 2004Large thickness of heavy nuclei brings in a new scale into the pQCD description of hard processes in nuclear environment. The familiar linear $k_{\perp}$-factorization breaks down and must be replaced by a new concept of the nonlinear $k_{\perp}$-factorization ... More
The perspectives of decoding the nature of the a0(980) and f0(980) mesons and of defining the relative phase between the three-gluon and one-photon amplitudes in the J/psi decaysApr 22 2003It is argued that the search of the J/psi --> f0(980)omega and J/psi --> a0(980)rho decays and the more precise definition of B(J/psi --> f0(980)phi) are the urgent purposes in the J/\psi spectroscopy. It is shown that the study of the omega-rho0 interference ... More
Light Scalars in Field TheoryOct 15 2008Outline: 1. Introduction, 2. Confinement, chiral dynamics and light scalar mesons, 3. Chiral shielding of \sigma(600), chiral constraints, \sigma(600), f_0(980) and their mixing in \pi\pi\to\pi\pi, \pi\pi\to K\bar K, and \phi\to\gamma\pi0\pi0, 4. The ... More
Random data Cauchy theory for supercritical wave equations I: Local theoryJul 10 2007We study the local existence of strong solutions for the cubic nonlinear wave equation with data in $H^s(M)$, $s<1/2$, where $M$ is a three dimensional compact riemannian manifold. This problem is supercritical and can be shown to be strongly ill-posed ... More
Image space projection for low-rank signal estimation: Modified Gauss-Newton methodMar 04 2018Jun 23 2019The paper is devoted to the solution of a weighted nonlinear least squares problem for low-rank signal estimation, which is related to Hankel structured low-rank approximation problems. A modified weighted Gauss-Newton method (MGN), which uses projection ... More
Asymmetry of $^{56}$Ni ejecta and polarization in type IIP supernova 2004djAug 21 2006I study a problem, whether the asymmetry of a $^{56}$Ni ejecta that results in the asymmetry of the H$\alpha$ emission line at the nebular epoch of the type IIP supernova SN 2004dj is able also to account for the recently detected polarization of the ... More
Non-Abelian Lovelock-Born-Infeld Topological Black HolesSep 02 2009Oct 24 2009We present the asymptotically AdS solutions of the Einstein gravity with hyperbolic horizons in the presence of $So(n(n-1)/2-1, 1)$ Yang-Mills fields governed by the non-Abelian Born-Infeld lagrangian. We investigate the properties of these solutions ... More
Gaussian measures associated to the higher order conservation laws of the Benjamin-Ono equationSep 24 2011Jul 04 2012Inspired by the work of Zhidkov on the KdV equation, we perform a construction of weighted gaussian measures associated to the higher order conservation laws of the Benjamin-Ono equation. The resulting measures are supported by Sobolev spaces of increasing ... More
Stability of the Lepton-Flavor Mixing Matrix Against Quantum CorrectionsJun 24 1999Recent neutrino experiments suggest the strong evidences of tiny neutrino masses and the lepton-flavor mixing. Neutrino-oscillation solutions for the atmospheric neutrino anomaly and the solar neutrino deficit can determine the texture of neutrino mass ... More
Yukawa Interaction from a SUSY Composite ModelSep 04 1997We present a composite model that is based on non-perturbative effects of N=1 supersymmetric SU(N_C) gauge theory with N_f=N_C+1 flavors. In this model, we consider N_C=7, where all matter fields in the supersymmetric standard model, that is, quarks, ... More
Static Configurations of Dark Energy and Dark MatterSep 26 2005Dec 08 2005We study static configurations of dark matter coupled to a scalar field responsible for the dark energy of the Universe. The dark matter is modelled as a Fermi gas within the Thomas-Fermi approximation. The mass of the dark matter particles is a function ... More
Colour transparency: a novel test of QCD in nuclear interactionsApr 20 1993Colour transparency is a cute and indispensable property of QCD as the gauge theory of strong interaction. CT tests of QCD consist of production of the perturbative small-sized hadronic state and measuring the strngth of its non-perturbative diffraction ... More
Intrinsic $k_{\perp}$ in the pomeronMay 31 1999Aug 20 1999In a consistent QCD approach to diffractive DIS gluons in the pomeron have soft $z_{g}$ distribution and very broad intrinsic $k_{\perp}$ distribution. The latter has not yet been incorporated into diffractive Monte-Carlo generators (RAPGAP,....). I argue ... More
An example of a 16-vertex Folkman edge (3,4)-graph without 8-cliquesFeb 12 2006In this paper we prove a new upper bouhd on an edge Folkman number. In a previous paper we have proved that this bound is exact.
Modified Gauss-Newton method in low-rank signal estimationMar 04 2018The paper is devoted to the solution of a weighted non-linear least-squares problem for low-rank signal estimation, which is related Hankel structured low-rank approximation problems. The solution is constructed by a modified weighted Gauss-Newton method. ... More
The Z\to c\bar c\toγγ^{\ast}, Z\to b\bar b\toγ γ^{\ast} triangle diagrams and the Z\toγψ, Z\to γΥ decaysMay 17 2010Sep 14 2010It is expounded the approach to the Z\to\gamma\Psi and Z\to\gamma\Upsilon decay study, based on the sum rules for the Z\to c\bar c\to\gamma\gamma^{\ast} and Z\to b\bar b\to\gamma\gamma^{\ast} amplitudes and their derivatives. The branching ratios of the ... More
Once more about gauge invariance in φ\toγ\pi0\pi0Jun 01 2006Oct 21 2007It is argued that the realization of gauge invariance condition as a consequent of cancellation between the \phi\to\gamma f0\to\gamma\pi0\pi0 resonance contribution and a \phi\to\gamma\pi0\pi0 background one, suggested in Ref. [1], is misleading.
Properties of the light scalar mesons face experimental dataSep 26 2006Dec 05 2006The following topics are considered. 1) Confinement, chiral dynamics, and light scalar mesons. 2) Chiral shielding of the \sigma(600) 3)The \phi meson radiative decays about nature of light scalar resonances. 4) The J/\psi decays about nature of light ... More
Light Scalar MesonsDec 13 2004Dec 14 2004The crucial points of physics of light scalar mesons are discussed. The special attention is given to the chiral shielding of lightest scalar mesons and the production of the well established light scalar mesons in the \phi radiative decays. Arguments ... More
Relative phase between the three-gluon and one-photon amplitudes of the J/psi decaysOct 04 2001It is shown that the study of the \omega-\rho interference pattern in the J/psi -> (rho+omega)eta -> pi+pi-eta decay provides evidence for the large (nearly 90 degrees) relative phase between the isovector one-photon and three-gluon decay amplitudes.
Two Particle Azimuthal Correlation Measurements in PHENIXOct 02 2002Oct 10 2002Two particle azimuthal correlation functions are presented for charged hadrons produced in Au-Au collisions at RHIC sqrt(s_NN)=200 GeV.The correlation functions indicate sizeable asymmetries and anisotropies. The trend of the asymmetries is compatible ... More
Invariant measure for a three dimensional nonlinear wave equationJul 10 2007We study the long time behavior of the subcritical (subcubic) defocussing nonlinear wave equation on the three dimensional ball, for random data of low regularity. We prove that for a large set of radial initial data in $\cap_{s<1/2} H^s(B(0,1))$ the ... More
Effective quantum number for axially symmetric problemsAug 15 2014We generalize the universal effective quantum number introduced earlier for centrally symmetric problems. The proposed number determines the semiclassical quantization condition for axially symmetric potentials.
Propagation of a Dark Soliton in a Disordered Bose-Einstein CondensateJun 01 2005Sep 26 2005We consider the propagation of a dark soliton in a quasi 1D Bose-Einstein condensate in presence of a random potential. This configuration involves nonlinear effects and disorder, and we argue that, contrarily to the study of stationary transmission coefficients ... More
Unnatural Oscillon Lifetimes in an Expanding BackgroundApr 19 2006Jul 11 2006We consider a classical toy model of a massive scalar field in 1+1 dimensions with a constant exponential expansion rate of space. The nonlinear theory under consideration supports approximate oscillon solutions, but they eventually decay due to their ... More
Non-linear Matter Spectrum for a Variable Equation of StateFeb 17 2010Apr 10 2014We study the growth of matter perturbations beyond the linear level in cosmologies in which the dark energy has a variable equation of state. The non-linear corrections result in shifts in the positions of the maximum, minima and nodes of the spectrum ... More
Unifying aspects of polarization of vector mesons from hard production in DIS and at TevatronAug 08 2001Virtual photons have both the transverse and longitudinal polarization. In the inclusive DIS the impact of longitudinal photons, quantified by R=sigmaL/\igmaT sim 0.2, is marginal, but in diffractive DIS with excitation of small mass hadronic states or ... More
Incomplete Tribonacci-Lucas numbers and polynomialsApr 16 2014In this paper, we define Tribonacci-Lucas polynomials and present Tribonacci-Lucas numbers and polynomials as a binomial sum. Then, we introduce incomplete Tribonacci-Lucas numbers and polynomials. In addition we derive recurrence relations, some properties ... More
Replay to hep-ph/0606266Jul 18 2006Jul 20 2006The \phi\to\gamma\pi\pi amplitude is found from the e+e-\to\gamma\pi\pi amplitude suggested in Ref. hep-ph/0606266. It is shown that the found amplitude differs essentially from that studied in Refs. hep-ph/0606266 and [3]. It is noticed that the suggestion ... More
Study of Light Scalars, the learned LessonsSep 02 2011Attention is paid to the production mechanisms of the light scalars that reveal their nature. In the linear sigma model it is revealed the chiral shielding of the \sigma(600) meson and shown that the \sigma field is described by its four-quark component. ... More
Radiative decays of φ-meson and nature of light scalar resonancesJan 31 2002Based on gauge invariance, we show that the new threshold phenomenon is discovered in the \phi radiative decays \phi\to\gamma a0\to\gamma\pi0\eta and \phi\to\gamma f0\to\gamma\pi0\pi0. This enables to conclude that production of the lightest scalar mesons ... More
On nature of scalar a_0(980) and f_0(980)-mesonsOct 29 1999It is presented a critical consideration of all unusual properties of the scalar a_0(980) and f_0(980)-mesons in the four-quark, two-quark and molecular models. The arguments are adduced that the four-quark model is more preferable. It is discussed the ... More
Random data Cauchy theory for supercritical wave equations II : A global existence resultJul 10 2007We prove that the subquartic wave equation on the three dimensional ball $\Theta$, with Dirichlet boundary conditions admits global strong solutions for a large set of random supercritical initial data in $\cap_{s<1/2} H^s(\Theta)$. We obtain this result ... More
Two and Three Particle Flavor Dependent CorrelationsOct 12 2005The PHENIX collaboration has developed novel methodologies for reliable extraction of jet functions from two and three particle azimuthal correlation functions measured at mid-rapidity in Au+Au collisions at $\sqrt s=200$ GeV. The extracted jet shape ... More
Extraction of jet topology using three particle correlationsSep 25 2006Recent theoretical studies have indicated that the topological features of away-side jet fragments can be significantly altered by medium-induced modifications. The leading candidates resulting from such modifications are Mach Cones and deflected jets. ... More
Chern invariants of some flat bundles in the arithmetic Deligne cohomologyApr 09 2006In this note, we investigate the Chern classes of flat bundles in the arithmetic Deligne Cohomology, introduced by Green-Griffiths, Asakura-Saito. We show nontriviality of the Chern classes in some cases and the proof also indicates that generic flat ... More
Stability of tangent bundle on the moduli space of stable bundles on a curveNov 01 2011Feb 12 2014In this paper, we prove that the tangent bundle of the moduli space $\cSU_C(r,d)$ of stable bundles of rank $r>2$ and of fixed determinant of degree $d$ (such that $(r,d)=1$), on a smooth projective curve $C$ is always stable, in the sense of Mumford-Takemoto. ... More
Cohomological invariants of a variation of flat connectionApr 20 2015Sep 23 2015In this paper, we apply the theory of Chern-Cheeger-Simons to construct canonical invariants associated to a $r$-simplex whose points parametrize flat connections on a smooth manifold $X$. These invariants lie in degrees $(2p-r-1)$-cohomology with $C/Z$-coefficients, ... More
Line shape of ψ(3770) in e^+e^-\to D\bar DAug 21 2012Dec 10 2012Interference phenomena observed in the $\psi(3770)$ resonance region in the reactions $e^+e^-$ $\to$ $ D\bar D$ are analyzed. To avoid ambiguities in the determination of the $\psi(3770)$ resonance parameters, when analyzing data between the $D\bar D$ ... More
Lightest Scalar Resonances and the Dynamics of the γγ\toππ ReactionsOct 13 2008The high-statistics Belle data on the \gamma\gamma\to\pi^+\pi^- and \gamma\gamma\to\pi^0\pi^0 reactions have been jointly analyzed. The main dynamical mechanisms of these reactions for energies below 1.5 GeV have been revealed. It has been shown that ... More
Manifestation of the $a^0_0(980)-f_0(980)$ mixing in the reaction $π^-p\toηπ^0n$ on a polarized targetMay 14 2004Oct 15 2004It is argued that the single-spin asymmetry in the reaction $\pi^-p\to a_0^0(980)n\to(\eta\pi^0)_S n$ is extremely sensitive to the mixing of the $a^0_0(980)$ and $f_0(980)$ resonances. It is shown that at low momentum transfers (namely, in any one of ... More
Mechanisms of the $f_0(980)$ production in the reaction $π^-p\toπ^0 π^0n$Jul 24 2001The model of the pure one-pion exchange mechanism, which gives a good description of the GAMS results on the alteration of the $S$-wave $\pi^0\pi^0$ mass spectrum in the $f_0(980)$ region in the reaction $\pi^-p\to\pi^0\pi^0n$ with increasing $-t$, is ... More
Description of the ψ(3770) resonance interfering with the backgroundFeb 18 2013Mar 26 2013The parameters of the interfering $\psi(3770)$ resonance should be determined from the data on the reactions $e^+e^-$\,$\to$\,$D\bar D$ with the use of the models satisfying the elastic unitarity requirement. The selection of such models can be realized ... More
f0(980) and a0(980) resonances near γγ\to K^+K^- and γγ\to K^0\bar K^0 reaction thresholdsOct 02 2012High-statistics data on the reactions $\gamma\gamma\to K^+K^-$ and $\gamma\gamma\to K^0\bar K^0$ are the last missing link in investigations of the light scalar mesons $f_0(980)$ and $a_0(980)$ in photon-photon collisions. It is believed that $f_0(980)$ ... More
Light Scalar Mesons in Photon-Photon CollisionsMay 13 2009Sep 02 2011The light scalar mesons, discovered over forty years ago, became a challenge for the naive quark-antiquark model from the outset. At present the nontrivial nature of these states is no longer denied practically anybody. Two-photon physics has made a substantial ... More
New explanation of the GAMS results on the $f_0(980)$ production in the reaction $π^-p\to π^0π^0n$Feb 10 1998Jul 14 1998The observed alteration of the S-wave $\pi^0\pi^0$ mass spectrum in the reaction $\pi^-p\to\pi^0\pi^0n$ with increasing $-t$, i.e., the disappearance of a dip and the appearance of a peak in the region of the $f_0(980)$ resonance as $-t$ increases, is ... More
Nonvanishing magnetic field in pure electrostatic systems at rest in the curved space-time of EarthJun 10 2019Solutions of the Maxwell equations for electrostatic systems at rest on the rotating Earth's surface are shown to exhibit a nonvanishing magnetic field despite zero electric currents in the system. Such a field is of pure geometric origin, and in contrast ... More
Circumstellar Na I and Ca II lines of type Ia supernovae in symbiotic scenarioJan 29 2008Formation of circumstellar lines of Na I and Ca II in type Ia supernovae is studied for the case, when supernova explodes in a binary system with a red giant. The model suggests a spherically-symmetric wind and takes into account ionization and heating ... More
Broad emission lines from opaque electron-scattering environment of SN 1998SJun 13 2001I propose that broad narrow-topped emission lines with full width at zero intensity >20000 km/s, seen in early-time spectra of SN 1998S, originate from a dense circumstellar gas and not from the supernova ejecta. The tremendous line width is the result ... More
Circumstellar interaction in type Ibn supernovae and SN 2006jcAug 05 2009I analyse peculiar properties of light curve and continua of enigmatic Ibn supernovae, including SN 2006jc, and argue in favour of the early strong circumstellar interaction. This interaction explains the high luminosity and fast flux rise of SN 1999cq, ... More
Strong decays of P wave baryons in the $1/N_c$ expansionApr 18 2005The hadronic decays of non-strange negative parity baryons are analyzed in the framework of the 1/Nc expansion. A complete basis of spin-flavor operators for the pseudoscalar meson S and D partial wave amplitudes is established to order 1/Nc and the unknown ... More
Two and Three parametric regular generalizations of spherically symmetric and axially symmetric metricsNov 22 2002Regular generalizations of spherically and axially symmetric metrics and their properties are considered. Newton gravity law generalizations are reduced for null geodesic.
Stripes ordering in self-stratification experiments of binary and ternary granular mixturesApr 25 2000The self-stratification of binary and ternary granular mixtures has been experimentally investigated. Ternary mixtures lead to a particular ordering of the strates which was not accounted for in former explanations. Bouncing grains are found to have an ... More
Partition test and sexual motivation in male miceAug 02 2007Theoretical analysis of own and literature investigations of sexual motivation with the use of the partition test [Kudryavtseva, 1987, 1994] in male mice was carried out. It has been shown that appearance of a receptive female in the neighboring compartment ... More
Spin Dependence of Diffractive Vector Meson ProductionAug 24 1999Aug 26 1999I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS. SCHNC in diffractive vector meson production is an unique probe of the spin-orbit coupling and Fermi motion of quarks in vector mesons. ... More
Helicity Flip in Diffractive DISAug 26 1999I review new results on s-channel helicity nonconservation (SCHNC) in diffractive DIS. I discuss how by virtue of unitarity diffractive DIS gives rise to spin structure functions which were believed to vanish at x << 1. These include tensor polarization ... More
Asymptotic behaviour of the total cross section of p-p scattering and the Akeno cosmic ray dataApr 21 1993I present a new determination of the total cross section for proton-proton collisions from the recent Akeno results on absorption of the cosmic ray protons in the p-Air collisions. Extrapolation to the SSC energy suggests $\sigma_{tot}(p-p) \approx (160-170) ... More
Problem of Light Scalar MesonsOct 04 2004The following topics are considered. 1. Confinement, chiral dynamics and light scalar mesons. 2. $\phi$-meson radiative decays about nature of light scalar resonances. Arguments in favor of the four-quark model of the $a_0(980)$ and $f_0(980)$ mesons ... More
Analysis of nature of phi -> gamma pi0 eta and phi -> gamma pi0 pi0 decaysOct 04 2001We study interference patterns in the phi -> gamma a0 + pi0 rho -> gamma pi eta and phi -> gamma f0 + pi0 rho -> gamma pi0 pi0 reactions. Taking into account the interference, we fit the experimental data and show that the background reaction does not ... More
On the Nature of the Scalar a_0(980) and f_0(980)-MesonsApr 05 1999It is presented a critical consideration of all unusual properties of the scalar $a_0(980)$ and $f_0(980)$-mesons in the four-quark, two-quark and molecular models. The arguments are adduced that the four-quark model is more preferable. It is discussed ... More
Production of pseudovector ($J^{PC}=1^{++}$) heavy quarkonia by virtual $Z$ boson in $e^+e^-$ collisionsMar 11 1996It is shown that $BR(\chi_{b1}(1P)\rightarrow Z\rightarrow e^+e^-)\simeq 3.3\cdot 10^{-7}$, $BR(\chi_{b1}(2P)\rightarrow Z\rightarrow e^+e^-)\simeq 4.1\cdot 10^{-7}$ and $BR(\chi_{c1}(1P)\rightarrow Z\rightarrow e^+e^-)\simeq 10^{-8}$ that give a good ... More
Light Scalar Mesons as Manifestation of Spontaneously Broken Chiral SymmetryJan 20 2010Attention is paid to the production mechanisms of light scalars that reveal their nature. We reveal the chiral shielding of the \sigma(600) meson. We show that the kaon loop mechanism of the \phi radiative decays, ratified by experiment, points to the ... More
Henon-Heiles Hamiltonian for Coupled Upper-Hybrid and Magnetoacoutic Waves in Magnetized PlasmasJul 24 1995We show that the coupled mode equations for the stationary propagation of upper--hybrid and magnetoacoustic waves in magnetized electron--ion plasmas with negative group dispersion can be exactly derived from the generalized \Henon--Heiles Hamiltonian. ... More
Identification of exotic jet topologies via three particle correlations in PHENIXNov 17 2005Modifications of jet properties resulting from the coupling of jets to the strongly interacting matter produced in RHIC collisions are of great current interest. In recent work, the PHENIX collaboration has applied a novel technique to the analysis of ... More
Luminosity source in supernova ASASSN-15nx with long linear light curveJun 28 2019The available spectra of the anomalous supernova ASASSN-15nx permit us to rule out the radioactivity and circumstellar interaction as the luminosity source. I propose an alternative mechanism for the ASASSN-15nx luminosity based on the interaction of ... More
Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey: I The PleiadesApr 12 2012We present the results of a deep wide-field near-infrared survey of the entire Pleiades cluster recently released as part of the UKIRT Infrared Deep Sky (UKIDSS) Galactic Clusters Survey (GCS) Data Release 9 (DR9). We have identified a sample of ~1000 ... More
Decay $X(3872)\toπ^0π^+π^-$ and $S$-wave $D^0\bar D^0 \toπ^+π^-$ scattering lengthApr 04 2019The isospin-breaking decay $X(3872)\to(D^*\bar D+ \bar D^*D) \to\pi^0D\bar D\to\pi^0\pi^+\pi^-$ is discussed. In its amplitude there is a triangle logarithmic singularity, due to which the dominant contribution to $BR(X(3872)\to\pi^0\pi^+\pi^-)$ comes ... More
Exotic $ρ^\pmρ^0$ state photoproductionJan 22 1999Aug 26 1999It is shown that the list of unusual mesons planned for a careful study in photoproduction can be extended by the exotic states $X^\pm(1600)$ with $I^G(J ^{PC})=2^+(2^{++})$ which should be looked for in the $\rho^\pm\rho^0$ decay channels in the reactions ... More
Mechanisms of the reaction pi^-p --> a^0_0(980)n --> p-^0 eta n at high energiesOct 18 1996The main dynamical mechanisms of the reaction $\pi^-p \rightarrow a^0_0 (980)n \rightarrow \pi^0\eta n$ at high energies, currently investigated at Serpukhov and Brookhaven, are considered in detail. It is shown that the observed forward peak in its differential ... More
η(1475) and f_1(1420) resonances in γγ* collisions and J/ψ\toγ(ρρ, γρ^0, γφ) decaysMay 04 2011Aug 27 2011The available data on the $Q^2$ dependence of the $\gamma\gamma*(Q^2)\to K\bar K\pi$ reaction cross section in the energy region 1.35-1.55 GeV is explained by the $\eta(1475)$ resonance production in contrast to their conventional interpretation with ... More
Nature of the a_0(980) Meson in the Light of Photon-Photon CollisionsMar 26 2010Jun 15 2010New high-statistics Belle data on the reaction \gamma\gamma\to\pi^0\eta are analyzed to clarify the two-photon production mechanisms and the nature of the a_0(980) meson. The obtained solution for the amplitude \gamma\gamma\to\pi^0\eta is consistent with ... More
Effective Lagrangians Induced by the Anomalous Wess-Zumino Action and $I^G(J^{PC})=1^-(1^{-+})$ Exotic StatesOct 10 2001A simple dynamical model for the exotic waves with $I^G(J^{PC})=1^-(1^{-+})$ in the reactions $\rho\pi\to\rho\pi$, $\rho\pi\to\eta\pi$, $\rho\pi\to\eta'\pi$, $ \rho\pi\to(K^*\bar K+\bar K^*K)$, and in the related ones, is constructed beyond the scope ... More
Pulsar Wind Nebulae ModelingNov 27 2013Pulsar Wind Nebulae (PWNe) are ideal astrophysical laboratories where high energy relativistic phenomena can be investigated. They are close, well resolved in our observations, and the knowledge derived in their study has a strong impact in many other ... More
Neutron star crust beyond the Wigner-Seitz approximationSep 24 2007For more than three decades, the inner crust of neutron stars, formed of a solid lattice of nuclear clusters coexisting with a gas of electrons and neutrons, has been traditionally studied in the Wigner-Seitz approximation. The validity of this approximation ... More
Constraint on the internal structure of a neutron star from Vela pulsar glitchesJul 20 2016Pulsars are spinning extremely rapidly with periods as short as about $1.4$ milliseconds and delays of a few milliseconds per year at most, thus providing the most accurate clocks in the Universe. Nevertheless, sudden spin ups have been detected in some ... More
Self-interaction errors in nuclear energy density functionalsDec 21 2010When applied to a single nucleon, nuclear energy density functionals may yield a non-vanishing internal energy thus implying that the nucleon is interacting with itself. It is shown how to avoid this unphysical feature for semi-local phenomenological ... More
Propagation of H and He cosmic ray isotopes in the Galaxy: astrophysical and nuclear uncertaintiesOct 27 2012Observations of light isotopes in cosmic rays provide valuable information on their origin and propagation in the Galaxy. Using the data collected by the AMS-01 experiment in the range ~0.2-1.5 GeV/nucleon, we compare the measurements on 1H, 2H, 3He, ... More
The system of three vortexes of two dimensional ideal hydrodinamics as a new example of the (integrable) Nambu- Poisson mechanicsMar 31 1998A Nambu-Poisson formulation of the system of three ordinary differential equations describing dynamics of three vortexes of the ideal two-dimensional hydrodynamics is given. The system is integrated by quadratures.