Results for "J. Malecki"

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Poisson kernel and Green function of the ball in real hyperbolic spacesDec 14 2005Let $(X_t)_{t\geq0}$ be the $n$-dimensional hyperbolic Brownian motion, that is the diffusion on the real hyperbolic space $\D^n$ having the Laplace-Beltrami operator as its generator. The aim of the paper is to derive the formulas for the Gegenbauer ... More
Hitting distributions of planar Brownian motionMar 14 2019The purpose of the paper is to find the joint distribution of the hitting time and place of two-dimensional Brownian motion hitting the negative horizontal axis. We provide various formulas for Green functions as well as for the conditional distributions. ... More
Hitting half-spaces by Bessel-Brownian diffusionsApr 11 2009The purpose of the paper is to find explicit formulas describing the joint distributions of the first hitting time and place for half-spaces of codimension one for a diffusion in $\R^{n+1}$, composed of one-dimensional Bessel process and independent n-dimensional ... More
Bessel Potentials, Hitting Distributions and Green FunctionsDec 07 2006The purpose of this paper is to find explicit formulas for basic objects pertaining the local potential theory of the operator $(I-\Delta)^{\alpha/2}$, $0<\alpha<2$. The potential theory of this operator is based on Bessel potentials $J_{\alpha}=(I-\Delta)^{-\alpha/2}$. ... More
Hitting hyperbolic half-spaceNov 02 2011Let X^\mu={X_t^\mu;t>=0}, \mu>0, be the n-dimensional hyperbolic Brownian motion with drift, that is a diffusion on the real hyperbolic space H^n having the Laplace-Beltrami operator with drift as its generator. We prove the reflection principle for X^\mu, ... More
Heat kernel estimates for the Bessel differential operator in half-lineJan 12 2015In the paper we consider the Bessel differential operator L^(\mu)=\dfrac{d^2}{dx^2}+\dfrac{2\mu+1}{x}\dfrac{d}{dx} in half-line (a,\infty), a>0, and its Dirichlet heat kernel p_a^(\mu)(t,x,y). For \mu=0, by combining analytical and probabilistic methods, ... More
Strong solutions of non-colliding particle systemsJul 04 2014We study systems of stochastic differential equations describing positions x_1,x_2,...,x_p of p ordered particles, with inter-particles repulsions of the form H_{ij}(x_i,x_j)/(x_i-x_j). We show the existence of strong and pathwise unique non-colliding ... More
Dirichlet heat kernel for the Laplacian in a ballDec 06 2016Apr 03 2017We provide sharp two-sided estimates on the Dirichlet heat kernel $k_1(t,x,y)$ for the Laplacian in a ball. The result accurately describes the exponential behaviour of the kernel for small times and significantly improves the qualitatively sharp results ... More
3-Body Dynamics in a (1+1) Dimensional Relativistic Self-Gravitating SystemJun 11 2003Jul 12 2004The results of our study of the motion of a three particle, self-gravitating system in general relativistic lineal gravity is presented for an arbitrary ratio of the particle masses. We derive a canonical expression for the Hamiltonian of the system and ... More
Hitting times of Bessel processesSep 17 2010Jun 06 2011Let $T_1^{(\mu)}$ be the first hitting time of the point 1 by the Bessel process with index $\mu\in \R$ starting from $x>1$. Using an integral formula for the density $q_x^{(\mu)}(t)$ of $T_1^{(\mu)}$, obtained in Byczkowski, Ryznar (Studia Math., 173(1):19-38, ... More
Inflationary Quantum Cosmology: General Framework and Exact Bianchi I SolutionJul 29 2004Sep 11 2004Using the methods of loop quantum gravity, we derive a framework for describing an inflationary, homogeneous universe in a purely quantum theory. The classical model is formulated in terms of the Ashtekar-Sen connection variables for a general subclass ... More
Bose-Einstein correlations and b-bbar correlations in pp collisions with LHCbSep 26 2018Bose-Einstein correlations for same-sign charged pions and kinematic b-bbar correlations in proton-proton collisions at a center-of-mass energy of 7 and 8 TeV are studied by the LHCb experiment. The dependence of Bose-Einstein correlation parameters on ... More
The Two Dimensional Kondo Model with Rashba Spin-Orbit CouplingAug 17 2007Sep 11 2007We investigate the effect that Rashba spin-orbit coupling has on the low energy behaviour of a two dimensional magnetic impurity system. It is shown that the Kondo effect, the screening of the magnetic impurity at temperatures T < T_K, is robust against ... More
Chaos in an Exact Relativistic 3-body Self-Gravitating SystemJan 23 2003We consider the problem of three body motion for a relativistic one-dimensional self-gravitating system. After describing the canonical decomposition of the action, we find an exact expression for the 3-body Hamiltonian, implicitly determined in terms ... More
Nonequilibrium conductance of asymmetric nanodevices in the Kondo regimeJun 19 2009Jan 25 2010The scaling properties of the conductance of a Kondo impurity connected to two leads that are in or out of equilibrium has been extensively studied, both experimentally and theoretically. From these studies, a consensus has emerged regarding the analytic ... More
Sharp estimates of transition probability density for Bessel process in half-lineSep 12 2013In this paper we study the Bessel process R_t^{(\mu)} with index \mu\neq 0 starting from x>0 and killed when it reaches a positive level a, where x>a>0. We provide sharp estimates of the transition probability density p_a^{(\mu)}(t,x,y) for the whole ... More
The Influence of Interference on the Kondo Effect in a Quantum DotJul 19 2010We study the Kondo effect in a model system of a quantum dot embedded in an Aharanov-Bohm ring connected to two leads. By transforming to the scattering basis of the direct inter-lead tunneling, we are able to describe precisely how the Kondo screening ... More
Multidimensional Yamada-Watanabe theorem and its applications to particle systemsAug 06 2011Nov 14 2012A multidimensional version of the Yamada-Watanabe theorem is proved. It implies a spectral matrix Yamada-Watanabe theorem. It is also applied to particle systems of squared Bessel processes, corresponding to matrix analogues of squared Bessel processes: ... More
Wallach sets and squared Bessel particle systemsFeb 04 2016We determine the classical and the non-central Wallach sets $W_0$ and $W$ by classical probabilistic methods. We prove the Mayerhofer conjecture on $W$. We exploit the fact that $(x_0,\beta)\in W$ if and only if $x_0$ is the starting point and $2\beta$ ... More
Dirichlet heat kernel for the Laplacian in a ballDec 06 2016We provide sharp two-sided estimates on the Dirichlet heat kernel $k_1(t,x,y)$ for the Laplacian in a ball. The result accurately describes the exponential behaviour of the kernel for small times and significantly improves the qualitatively sharp results ... More
Spectral Properties of the Massless Relativistic Harmonic OscillatorJun 18 2010The spectral properties of the pseudo-differential operator $(-d^2/dx^2)^{1/2}+x^2$ are analyzed by a combination of functional integration methods and direct analysis. We obtain a representation of its eigenvalues and eigenfunctions, prove precise asymptotic ... More
The asymptotic behavior of the density of the supremum of Lévy processesOct 06 2013Let us consider a real L\'evy process X whose transition probabilities are absolutely continuous and have bounded densities. Then the law of the past supremum of X before any deterministic time t is absolutely continuous on (0,\infty). We show that its ... More
On squared Bessel particle systemsJul 19 2017We study the existence and uniqueness of SDEs describing squared Bessel particles systems in full generality. We define non-negative and non-colliding squared Bessel particle systems and we study their properties.
First passage times for subordinate Brownian motionsOct 03 2011Mar 02 2012Let X_t be a subordinate Brownian motion, and suppose that the Levy measure of the underlying subordinator has completely monotone density. Under very mild conditions, we find integral formulae for the tail distribution P(\tau_x > t) of first passage ... More
Sharp estimates of Green function of hyperbolic Brownian MotionFeb 03 2015The main objective of the work is to provide sharp two-sided estimates of $\lambda$-Green function of hyperbolic Brownian motion of a half-space. We strongly rely on recent results obtained by K. Bogus and J. Malecki [3], regarding precise estimates of ... More
Crossover in the two-impurity Kondo model induced by direct charge tunnelingSep 04 2010Oct 31 2011Quantum critical behavior in the two-impurity Kondo model requires the distinct separation of two scales, T_K >> T*, where T_K is the Kondo temperature and T* is the scale at which the system renormalizes away from the quantum critical point to a stable ... More
A Characterization of Wishart Processes and Wishart DistributionsJul 01 2016Aug 02 2016We characterize the existence of non-central Wishart distributions (with shape and non-centrality parameter) as well as the existence of solutions to Wishart stochastic differential equations (with initial data and drift parameter) in terms of their exact ... More
One-dimensional quasi-relativistic particle in the boxOct 26 2011May 25 2012Two-term Weyl-type asymptotic law for the eigenvalues of one-dimensional quasi-relativistic Hamiltonian (-h^2 c^2 d^2/dx^2 + m^2 c^4)^(1/2) + V_well(x) (the Klein-Gordon square-root operator with electrostatic potential) with the infinite square well ... More
A Characterization of Wishart Processes and Wishart DistributionsJul 01 2016May 22 2017A characterization of the existence of non-central Wishart distributions (with shape and non-centrality parameter) as well as the existence of solutions to Wishart stochastic differential equations (with initial data and drift parameter) in terms of their ... More
Quantum Gravity and InflationSep 03 2003Jul 28 2004Using the Ashtekar-Sen variables of loop quantum gravity, a new class of exact solutions to the equations of quantum cosmology is found for gravity coupled to a scalar field, that corresponds to inflating universes. The scalar field, which has an arbitrary ... More
Fourier-Bessel heat kernel estimatesMar 07 2015We provide sharp two-sided estimates of the Fourier-Bessel heat kernel and we give sharp two-sided estimates of the transition probability density for the Bessel process in (0,1) killed at 1 and killed or reflected at 0.
Hitting half-spaces or spheres by the Ornstein-Uhlenbeck type diffusionsSep 01 2011Nov 03 2011The purpose of the paper is to provide a general method for computing hitting distributions of some regular subsets D for Ornstein-Uhlenbeck type operators of the form 1/2\Delta + F\cdot\nabla, with F bounded and orthogonal to the boundary of D. As an ... More
Relationship between the size of camphor-driven rotor and its angular velocityApr 03 2017Aug 01 2017We consider a rotor made of two camphor disks glued below the ends of a plastic stripe. The disks are floating on a water surface and the plastic stripe does not touch the surface. The system can rotate around a vertical axis located at the center of ... More
Bifurcation in the angular velocity of a circular disk propelled by symmetrically distributed camphor pillsSep 19 2018Jan 28 2019We studied rotation of a disk propelled by a number of camphor pills symmetrically distributed at its edge. The disk was put on a water surface so that it could rotate around a vertical axis located at the disk center. In such a system, the driving torque ... More
Molecular self-organization: Predicting the pattern diversity and lowest energy state of competing ordering motifsFeb 16 2011Feb 17 2011Self-organized monolayers of highly flexible \Frechet dendrons were deposited on graphite surfaces by solution casting. Scanning tunneling microscopy (STM) reveals an unprecedented variety of patterns with up to seven stable hierarchical ordering motifs ... More
Measurement of the ratio of branching fractions of the decays $Λ^0_b\!\toψ(2S) Λ$ and $Λ^0_b\!\to J/ψΛ$Feb 06 2019Using $pp$ collisions corresponding to 3$\,\text{fb}^{-1}$ integrated luminosity, recorded by the LHCb experiment at centre-of-mass energies of 7 and 8$\,\text{TeV}$, the ratio of branching fractions \begin{align*} \mathcal{B}(\Lambda^0_b\!\to\psi(2S) ... More
Stability of spherical stellar systems I : Analytical resultsNov 22 1995The so-called ``symplectic method'' is used for studying the linear stability of a self-gravitating collisionless stellar system, in which the particles are also submitted to an external potential. The system is steady and spherically symmetric, and its ... More
Search for $CP$ violation through an amplitude analysis of $D^0 \rightarrow K^+ K^- π^+ π^-$ decaysNov 20 2018Mar 06 2019A search for $CP$ violation in the Cabibbo-suppressed $D^0 \rightarrow K^+ K^- \pi^+ \pi^-$ decay mode is performed using an amplitude analysis. The measurement uses a sample of $pp$ collisions recorded by the LHCb experiment during 2011 and 2012, corresponding ... More
Expected Performance of the ATLAS Experiment - Detector, Trigger and PhysicsDec 28 2008Aug 14 2009A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential ... More
Observation of $B^0_{(s)} \to J/ψp \overline{p}$ decays and precision measurements of the $B^0_{(s)}$ massesFeb 14 2019The first observation of the decays $B^0_{(s)} \to J/\psi p \overline{p}$ is reported, using proton-proton collision data corresponding to an integrated luminosity of $5.2{\text{fb}}^{-1}$, collected with the LHCb detector. These decays are suppressed ... More
Center Disorder in the 3D Georgi-Glashow ModelApr 15 1998We present a number of arguments relating magnetic disorder to center disorder, in pure Yang-Mills theory in D=3 and D=4 dimensions. In the case of the D=3 Georgi-Glashow model, we point out that the abelian field distribution is not adequatedly represented, ... More
The Impact of Galaxy Formation on the Diffuse Background RadiationOct 23 2000The far infrared background is a sink for the hidden aspects of galaxy formation. At optical wavelengths, ellipticals and spheroids are old, even at $z \sim 1.$ Neither the luminous formation phase nor their early evolution is seen in the visible. We ... More
Recoil Polarization for Delta Excitation in Pion ElectroproductionMay 23 2005We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W=1.23 GeV at Q^2=1.0 (GeV/c)^2, obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed ... More
Spinons and helimagnons in the frustrated Heisenberg chainFeb 23 2012We investigate the dynamical spin structure factor S(q,w) for the Heisenberg chain with ferromagnetic nearest (J1<0) and antiferromagnetic next-nearest (J2>0) neighbor exchange using bosonization and a time-dependent density-matrix renormalization group ... More
Non-adiabatic primordial fluctuationsNov 10 2009Apr 19 2010We consider general mixtures of isocurvature and adiabatic cosmological perturbations. With a minimal assumption set consisting of the linearized Einstein equations and a primordial perfect fluid we derive the second-order action and its curvature variables. ... More
Nuclear time-reversal violation and the Schiff moment of 225RaMar 22 2005May 12 2005We present a comprehensive mean-field calculation of the Schiff moment of the nucleus 225Ra, the quantity which determines the static electric dipole moment of the corresponding atom if time-reversal (T) invariance is violated in the nucleus. The calculation ... More
Solution of the Skyrme-Hartree-Fock equations in the Cartesian deformed harmonic-oscillator basis. (III) HFODD (v1.75r): a new version of the programMar 01 2000We describe the new version (v1.75r) of the code HFODD which solves the nuclear Skyrme-Hartree-Fock problem by using the Cartesian deformed harmonic-oscillator basis. Three minor errors that went undetected in the previous version have been corrected. ... More
On Zero-Mass Ground States in Super-Membrane Matrix ModelsJan 23 1997We recall a formulation of super-membrane theory in terms of certain matrix models. These models are known to have a mass spectrum given by the positive half-axis. We show that, for the simplest such matrix model, a normalizable zero-mass ground state ... More
Measurement of CP violation at a Neutrino FactoryMay 29 2001The prospects of measuring CP violation in the leptonic sector using the intense neutrino beams arising from muon decay in the straight sections of a muon accumulator ring (the so-called neutrino factory) are discussed.
Thermalization of Quantum Fields from Time-Reversal Invariant Evolution EquationsJun 14 2000We study the time evolution of correlation functions in closed quantum systems for nonequilibrium ensembles of initial conditions. For a scalar quantum field theory we show that generic time-reversal invariant evolutions approach equilibrium at large ... More
Permutation Group Symmetry and CorrelationsJun 11 2013Correlation factors are constructed that are consistent with the permutation symmetry group of N Fermions at given value of the filling factor.
Horizontal symmetry in the algebraic approach of genetic codeFeb 14 2013Using concepts of physics of elementary particles concerning the breaking of symmetry and grannd unified theory we propose to study with the algebraic approximation the degeneracy finded in the genetic code with the incorporation of a horizontal symmetry ... More
The winds of the hot massive first starsSep 07 2005We study dynamical aspects of circumstellar environment around massive zero-metallicity first stars. For this purpose we apply our NLTE wind models. We show that the hydrogen-helium stellar wind from stationary massive first generation (Population III) ... More
Inverted crossover resonance aiding laser cooling of $^{171}$YbMar 03 2016Apr 19 2016We observe an inverted crossover resonance in $\pi$-driven four-level systems, where $F'-F=0,+1$. The signal is observed through saturated absorption spectroscopy of the $(6s^{2})$ $^{1}S_{0}$ $-$ $(6s6p)$ $^{3}P_{1}$ transition in $^{171}$Yb, where the ... More
Hartree shift in unitary Fermi gasesMar 24 2011The Hartree energy shift is calculated for a unitary Fermi gas. By including the momentum dependence of the scattering amplitude explicitly, the Hartree energy shift remains finite even at unitarity. Extending the theory also for spin-imbalanced systems ... More
Coulomb blockade in electron transport through a C$_{60}$ molecule from first principlesMay 23 2005We present results of spin-unrestricted first-principles quantum transport for a gated C$_{60}$ molecule weakly contacted to Al electrodes, making emphasis on the role played by the electronic localization and the spin degree of freedom. As expected, ... More
Nuclear suppression of dileptons at forward rapiditiesDec 14 2010Data from E772 and E866 experiments on the Drell-Yan process exhibit a significant nuclear suppression at large Feynman xF. We show that a corresponding kinematic region does not allow to interpret this as a manifestation of coherence or a Color Glass ... More
Asymmetric Wolf-Rayet winds: implications for GRB afterglowsJan 25 2007Recent observations of Wolf-Rayet (WR) binaries WR151 and WR155 infer that their stellar winds are asymmetric. We show that such asymmetries can alter the stellar-wind bubble structure, bringing the wind-termination shock closer to the WR star. If the ... More
Unbiased estimators in Quantum Monte Carlo methods: application to liquid $^4$HeJan 18 1995A Monte Carlo algorithm for computing quantum mechanical expectation values of coordinate operators in many body problems is presented. The algorithm, that relies on the forward walking method, fits naturally in a Green's Function Monte Carlo calculation, ... More
Asymptotic cones and Assouad-Nagata dimensionOct 10 2006Oct 20 2006We prove the dimension of any asymptotic cone over a metric space X does not exceed the asymptotic Assouad-Nagata dimension of X. This improves a result of Dranishnikov and Smith who showed that dim(Y) does not exceed asymptotic Assouad-Nagata dimension ... More
A Plasma Instability Theory of Gamma-Ray Burst EmissionApr 02 1999A new theory for gamma-ray burst radiation is presented. In this theory, magnetic fields and relativistic electrons are created through plasma processes arising as a relativistic shell passes through the interstellar medium. The gamma-rays are produced ... More
Pi^0_1 ordinal analysis beyond first order arithmeticDec 11 2012In this paper we give an overview of an essential part of a Pi^0_1 ordinal analysis of Peano Arithmetic (PA) as presented by Beklemishev. This analysis is mainly performed within the polymodal provability logic GLP. We reflect on ways of extending this ... More
Fazendo 3D com uma camera soDec 14 2010Jan 29 2012A simple system to make stereo photography or videos based in just two mirrors was made in 1989 and recently adapted to a digital camera setup.
Enlarging Holograms Under White Light, a Way to Save Holographic MaterialMay 08 2009We developed techniques for employing holographic screens under white light, first exhibited to the public in 1989 (3) (4) which demonstrated the possibility of enlarging holograms already in 1990 (5). Fig. 1 shows how we encode views in a first step. ... More
White Light Colour Photography for Rendering Holoimages in a Diffractive ScreenApr 16 2009The capability of color encoding the continuous sequence of views from a scene was demonstrated previously by the author (1990). In the present work, the scheme for this process is shown where white light from a black and white object is diffracted at ... More
On the quality of the Olmec mirrors and its utilizationJan 29 2007Archaeological mirrors from the Olmec civilization were analyzed in the context of bibliography produced in the last two decades. Photographs of its images are showed as a proof of its good quality. Some suggestions are made on its probable utilization. ... More
Lagrangian and Hamiltonian for the Bondi-Sachs metricsMar 31 2004Feb 03 2015We calculate the Hilbert action for the Bondi-Sachs metrics. It yields the Einstein vacuum equations in a closed form. Following the Dirac approach to constrained systems we investigate the related Hamiltonian formulation.
Quartz Tuning Forks and Acoustic Phenomena - Application to Superfluid HeliumApr 09 2013Jan 30 2016Immersed mechanical resonators are well suited for probing the properties of fluids, since the surrounding environment influences the resonant characteristics of such oscillators in several ways. Quartz tuning forks have gained much popularity in recent ... More
Infrared dynamic polarizability of HD+ rovibrational statesJun 07 2011A calculation of dynamic polarizabilities of rovibrational states with vibrational quantum number $v=0-7$ and rotational quantum number $J=0,1$ in the 1s$\sigma_g$ ground-state potential of HD$^+$ is presented. Polarizability contributions by transitions ... More
Curvettes and clusters of infinitely near pointsMar 30 2009Jul 03 2011The aim of this paper is to revise the theory of clusters of infinitely near points for arbitrary fields. We describe in particular the intersection matrix of such a cluster, we introduce the notion of curvette over an arbitrary field and we relate it ... More
Phase transitions in systems of magnetic dipoles on a square lattice with quenched disorderSep 14 2008We study by Monte Carlo simulations the effect of quenched orientational disorder in systems of interacting classical dipoles on a square lattice. Each dipole can lie along any of two perpendicular axes that form an angle psi with the principal axes of ... More
Effective realization of random magnetic fields in compounds with large single-ion anisotropyJun 20 2016We show that spin $S=1$ system with large and random single-ion anisotropy can be at low energies mapped to a $S=1/2$ system with random magnetic fields. This is for example realized in Ni(Cl$_{1-x}$Br$_{x}$)$_2$-4SC(NH$_2$)$_2$ compound (DTNX) and therefore ... More
Application of Jitter Radiation: Gamma-ray Burst Prompt PolarizationSep 20 2013A high-degree of polarization of gamma-ray burst (GRB) prompt emission has been confirmed in recent years. In this paper, we apply jitter radiation to study the polarization feature of GRB prompt emission. In our framework, relativistic electrons are ... More
Equivalence between the Morita categories of etale Lie groupoids and of locally grouplike Hopf algebroidsMar 13 2007Any etale Lie groupoid G is completely determined by its associated convolution algebra C_c(G) equipped with the natural Hopf algebroid structure. We extend this result to the generalized morphisms between etale Lie groupoids: we show that any principal ... More
Superlogarithmic estimates on pseudoconvex domains and CR manifoldsOct 15 2004This paper is concerned with proving superlogarithmic estimates for the operator $\Box_b$ on pseudoconvex CR manifolds and using them to establish hypoellipticity of $\Box_b$ and of the $\bar{\partial}$-Neumann problem. These estimates are established ... More
Chaplygin's sphereSep 01 2004Chaplygin proved the integrability by quadratures of a round sphere, rolling without slipping on a horizontal plane, with center of mass at the center of the sphere, but with arbitrary moments of inertia. Although the system is integrable in every sense ... More
An addendum to `A rigidity property for the set of all characters induced by valuations'May 28 2013This corrects and amplifies some comments made in a paper by Robert Bieri and the author with the above title.
A characterization of Sobolev spaces on the sphere and an extension of Stolarsky's invariance principle to arbitrary smoothnessMar 23 2012In this paper we study reproducing kernel Hilbert spaces of arbitrary smoothness on the sphere $\mathbb{S}^d \subset \mathbb{R}^{d+1}$. The reproducing kernel is given by an integral representation using the truncated power function $(\boldsymbol{x} \cdot ... More
A remark on the structure of the Busemann representative of a polyconvex functionSep 23 2008Let W be a polyconvex function defined on the 2 x 2 real matrices. The Busemann representative f, say, of W is the largest possible convex representative of W. Writing L for the set of affine functions on R^{5} such that a(A, det A) is less than or equal ... More
A note on Positivity of the CM line bundleMay 11 2006Aug 09 2006We show that positivity of the CM line associated to a family of polarised varieties is intimately related to the stability of its members. We prove that the CM line is nef on any curve which meets the stable locus, and that it is pseudoeffective (i.e. ... More
Social Balance and the Bernoulli EquationJan 14 2017Dec 13 2017Since the 1940's there has been an interest in the question why social networks often give rise to two antagonistic factions. Recently a dynamical model of how and why such a balance might occur was developed. This note provides an introduction to the ... More
Observation of the doubly Cabibbo-suppressed decay $Ξ_{c}^{+}\to pφ$Jan 18 2019The doubly Cabibbo-suppressed decay $\Xi_{c}^{+}\to p\phi$ with $\phi\to K^{+}K^{-}$ is observed for the first time, with a statistical significance of more than fifteen standard deviations. The data sample used in this analysis corresponds to an integrated ... More
Search for lepton-universality violation in $B^+\to K^+\ell^+\ell^-$ decaysMar 21 2019A measurement of the ratio of branching fractions of the decays $B^+\to K^+\mu^+\mu^-$ and $B^+\to K^+e^+e^-$ is presented. The proton-proton collision data used correspond to an integrated luminosity of $5.0\,$fb$^{-1}$ recorded with the LHCb experiment ... More
Measurement of the mass and production rate of $Ξ_b^-$ baryonsJan 21 2019The first measurement of the production rate of $\Xi_b^-$ baryons in $pp$ collisions relative to that of $\Lambda_b^0$ baryons is reported, using data samples collected by the LHCb experiment, and corresponding to integrated luminosities of $1$, $2$ and ... More
Measurement of the $CP$-violating phase $φ_s$ from $B_{s}^{0}\to J/ψπ^+π^-$ decays in 13 TeV $pp$ collisionsMar 13 2019Decays of $B_{s}^{0}$ and $\overline{B}{}_{s}^{0}$ mesons into $J/\psi\pi^+\pi^-$ final states are studied in a data sample corresponding to 1.9 fb$^{-1}$ of integrated luminosity collected with the LHCb detector in 13 TeV $pp$ collisions. A time-dependent ... More
Search for the rare decay $B^{+} \rightarrow μ^{+}μ^{-}μ^{+}ν_{μ}$Dec 14 2018A search for the rare leptonic decay $B^{+} \rightarrow {\mu}^{+}{\mu}^{-}{\mu}^{+}{\nu}_{{\mu}}$ is performed using proton-proton collision data corresponding to an integrated luminosity of $4.7$ fb$^{-1}$ collected by the LHCb experiment. The search ... More
Measurement of $B^+$, $B^0$ and $Λ_b^0$ production in $p\mkern 1mu\mathrm{Pb}$ collisions at $\sqrt{s_\mathrm{NN}}=8.16\,{\rm TeV}$Feb 14 2019The production of $B^+$, $B^0$ and $\Lambda_b^0$ hadrons is studied in proton-lead collisions at a centre-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}}=8.16\,{\rm TeV}$ recorded with the LHCb detector at the LHC. The measurement uses a dataset ... More
Measurement of b-hadron fractions in 13 TeV pp collisionsFeb 18 2019Feb 25 2019The production fractions of $\overline{B}_s^0$ and $\Lambda_b^0$ hadrons, normalized to the sum of $B^-$ and $\overline{B}^0$ fractions, are measured in 13 TeV pp collisions using data collected by the LHCb experiment, corresponding to an integrated luminosity ... More
Model-independent observation of exotic contributions to $B^0\to J/ψ K^+π^-$ decaysJan 17 2019An angular analysis of $B^0\to J/\psi K^+\pi^-$ decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3~${\rm fb}^{-1}$ collected with the LHCb detector. The $m(K^+\pi^-)$ spectrum is divided into fine bins. ... More
Search for $CP$ violation in $D_s^+\to K_S^0 π^+$, $D^+\to K_S^0 K^+$ and $D^+\to φπ^+$ decaysMar 04 2019A search for charge-parity ($CP$) violation in Cabibbo-suppressed $D_s^+\to K_S^0 \pi^+$, $D^+\to K_S^0 K^+$ and $D^+\to \phi \pi^+$ decays is reported using proton-proton collision data, corresponding to an integrated luminosity of 3.8 fb$^{-1}$, collected ... More
Observation of $C\!P$ violation in charm decaysMar 20 2019A search for charge-parity ($C\!P$) violation in $D^0 \to K^- K^+$ and $D^0 \to \pi^- \pi^+$ decays is reported, using $pp$ collision data corresponding to an integrated luminosity of 6 $\mathrm{fb}^{-1}$ collected at a center-of-mass energy of 13 TeV ... More
Measurements of $CP$ asymmetries in charmless four-body $Λ_b$ and $Ξ_b^0$ decaysMar 15 2019A search for $CP$ violation in charmless four-body decays of $\Lambda_b$ and $\Xi_b^0$ baryons with a proton and three charged mesons in the final state is performed. To cancel out production and detection charge-asymmetry effects, the search is carried ... More
Study of the $B^0\to ρ(770)^0 K^*(892)^0$ decay with an amplitude analysis of $B^0\to (π^+π^-) (K^+π^-)$ decaysDec 17 2018An amplitude analysis of ${B^0\to (\pi^+\pi^-) (K^+\pi^-)}$ decays is performed in the two-body invariant mass regions ${300 < m(\pi^+\pi^-)<1100}$ MeV/$c^2$, accounting for the $\rho^0$, $\omega$, $f_0(500)$, $f_0(980)$ and $f_0(1370)$ resonances, and ... More
Measurement of the mass difference between neutral charm-meson eigenstatesMar 07 2019We report a measurement of the mass difference between neutral charm-meson eigenstates using a novel approach that enhances sensitivity to this parameter. We use $2.3\times 10^6$ $D^0\to K_S^0\pi^+\pi^-$ decays reconstructed in proton-proton collisions ... More
The 3-D composition of the Galactic interstellar medium. The hot phases and X-ray absorbing materialNov 19 2002We present maps of the Galactic X-ray Halo and constrain the location of X-ray absorbing gas using the X-ray radiation transfer as distance a indicator. Based on a consistent model of the soft X-ray background (SXRB) and the ROSAT all-sky survey, we derive ... More
Collisions of solid ice in planetesimal formationJan 18 2016We present collision experiments of centimetre projectiles on to decimetre targets, both made up of solid ice, at velocities of $15\,\mathrm{m\,s^{-1}}$ to $45\,\mathrm{m\,s^{-1}}$ at an average temperature of $\mathrm{T_{avg}}=255.8\pm0.7\,\mathrm{K}$. ... More
A model realisation of the Jaffe-Wilczek correlation for pentaquarksMar 22 2004We discuss a realisation of the pentaquark structure proposed by Jaffe and Wilczek within a simple quark model with colour-spin contact interactions and coloured harmonic confinement, which accurately describes the $\Delta-N$ splitting. In this model ... More
Recoil Polarization Measurements for Neutral Pion Electroproduction at Q^2=1 (GeV/c)^2 Near the Delta ResonanceSep 01 2005We measured angular distributions of differential cross section, beam analyzing power, and recoil polarization for neutral pion electroproduction at Q^2 = 1.0 (GeV/c)^2 in 10 bins of W across the Delta resonance. A total of 16 independent response functions ... More
Accuracy of traditional Legendre estimators of quadrupole ratios for the N to Delta transitionJul 06 2005We evaluate the accuracy of traditional estimators often used to extract N to Delta quadrupole ratios from cross section angular distributions for pion electroproduction. We find that neither M1+ dominance nor sp truncation is sufficiently accurate for ... More
Time-odd components in the mean field of rotating superdeformed nucleiFeb 10 1995Rotation-induced time-odd components in the nuclear mean field are analyzed using the Hartree-Fock cranking approach with effective interactions SIII, SkM*, and SkP. Identical dynamical moments ${{\cal J}^{(2)}}$ are obtained for pairs of superdeformed ... More