Antihydrogen production within a Penning-Ioffe trap

Slow antihydrogen (H) is produced within a Penning trap that is located within a quadrupole Ioffe trap, the latter intended to ultimately confine extremely cold, ground-state H[over ] atoms. Observed H[over ] atoms in this configuration resolve a debate about whether positrons and antiprotons can be brought together to form atoms within the divergent magnetic fields of a quadrupole Ioffe trap. The number of detected H atoms actually increases when a 400 mK Ioffe trap is turned on.     

Antiproton confinement in a Penning-Ioffe trap for antihydrogen

Antiprotons (p[over]) remain confined in a Penning trap, in sufficient numbers to form antihydrogen (H[over ) atoms via charge exchange, when the radial field of a quadrupole Ioffe trap is added. This first demonstration with p[over] suggests that quadrupole Ioffe traps can be superimposed upon p[over] and e(+) traps to attempt the capture of H[over] atoms as they form, contrary to conclusions of previous analyses.     

Dynamics of a charged particle bunch in a penning trap

The Lagrangean equations for gas dynamics of a spherical bunch of charged particles in a Penning trap are solved. The solution describes the pulsation of an inhomogeneous particle bunch whose center behaves as a spatial oscillator in a coordinate system rotating with the Larmor frequency.     

Parametric excitation of oscillations of charged particle bunches in a Penning trap

A self-similar solution is obtained for the self-consistent hydrodynamic equations describing the motion of an ellipsoid of charged particles in a Penning trap and in an rf trap. The conditions are determined for which a small periodic variation of the confining magnetic field in the Penning trap drives oscillations of the bunch. Zh. Tekh. Fiz. 67, 27–29 (January 1997)     

Dynamics of charged particles in a Penning trap

An automodel solution of self-consistent equations for an ellipsoidal cluster of Coulomb particles in a Penning trap is obtained.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 18–21, July, 1994.     

Three charged bosons confined in a two-dimension harmonic trap

A system of three charged bosons confined in a two-dimension harmonic trap has been investigated. We report a calculation for the energy spectrum of the low-lying states of a system of three charged bosons. The important feature of the low-lying states of three charged bosons in two-dimension space is obtained via an analysis the energy spectrum.     

Embedding of a relativistic charged particle

A charged particle following the Reissner-Weyl vacuum field-distribution shows in its interior a real singularity (the matter-tensor becomes infinite). By embedding the interior submanifoldds ²=g ₁₁·dr ²+g ₀₀·dt ² into a pseudo-Euclidean spaceE ₃:ds ²=dZ ₁ ² +dZ ₂ ² –dZ ₃ ² one finds that the embedded (r, t)-metric looks like a cone with the top liying in theZ ₁,Z ₂ plane. The general formulas of embedding the complete manifold into a pseudo-Euclidean spaceE ₆ are discussed.     

Cold highly charged ions in a cryogenic Paul trap

Narrow optical transitions in highly charged ions (HCIs) are of particular interest for metrology and fundamental physics, exploiting the high sensitivity of HCIs to new physics. The highest sensitivity for a changing fine structure constant ever predicted for a stable atomic system is found in Ir^17?+?. However, laser spectroscopy of HCIs is hindered by the large (～ 10⁶ K) temperatures at which they are produced and trapped. An unprecedented improvement in such laser spectroscopy can be obtained when HCIs are cooled down to the mK range in a linear Paul trap. We have developed a cryogenic linear Paul trap in which HCIs will be sympathetically cooled by ⁹Be^?+? ions. Optimized optical access for laser light is provided while maintaining excellent UHV conditions. The Paul trap will be connected to an electron beam ion trap (EBIT) which is able to produce a wide range of HCIs. This EBIT will also provide the first experimental input needed for the determination of the transition energies in Ir^17?+?, enabling further laser-spectroscopic investigations of this promising HCI.     

Behavior of a charged particle in a schwarzschild field

The influence of the De Witt self-action force on the motion of and electromagnetic emission from a charged particle in a Schwarzschild field is considered. It is shown that a charged particle in a Schwarzschild field is equivalent to a neutral particle of the same mass in a certain Reissner-Nordstrom field. A relationship is found between the power of the electromagnetic emission from an accelerated charge and the power of the thermal emission generated in a reference frame with the same acceleration at the event horizon. The quantum-mechanical problem of the motion of and emission from a charge in the field of a minihole is considered. Wave functions, the energy spectrum, and the widths of quasi-stationary levels are found with allowance for the De Witt self-action force. It is shown that the latter is important for large charges, when the solution becomes oscillatory. "Brainstorm" Little Science and Technology Enterprise. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 75–82, July, 1998.     

Antihydrogen production in a combined trap

In this paper we study the properties of a Paul trap with a superimposed magnetic field (combined trap) and discuss the possibility of using this trap to simultaneously store positrons and antiprotons to form antihydrogen.     

Formation of ordered structures of charged macroparticles in a photoemission trap

The possibility of confining positively charged macroscopic dust particles in a unique photoemission trap was studied. The spatial distributions of the potentials for a cylindrical geometry of a phototrap were obtained (by the particles in a cell method) and the dynamics of the formation of ordered structures of dust particles in the potential field of the trap was studied (by the molecular-dynamics method). The dependence of the number of dust particles confined by a phototrap on the particle energies and sizes and the buffer-gas pressure were obtained.     

Continuous quantum measurements of a particle in a Paul trap

We calculate the propagator of a particle caught in a Paul trap and subject to the continuous quantum measurement of its position. The probabilities of the measurement outputs, the possible trajectories of the particle, are also found. This enables us to propose a series of experiments that would allow us to compare the predictions of one of the models that describe the interaction between a measured quantum system and measuring device, namely the so-called restricted path-integral formalism, with the experiment.     

Anisotropic equipartition state in a charged particle beam

The purpose of this Letter is to conjecture a characterization of the anisotropic equipartition state. The anisotropic equipartition state is defined through a phase space density which is uniform on the invariant surface of ξ, where ξ is the ratio between the oscillation energies in the x- and y-directions. It is a version of the ergodic hypothesis where the invariant surface of ξ plays the role of the conserved energy. We show that the anisotropic equipartition state is characterized by the following properties: the development of an elliptical shape with increasing size along the x-direction, the presence of a coupling between transversal emittances, halo formation along a preferential direction, stationarity of the temperature and a growth of the entropy in the cascade form.     

Dynamics of a charged particle in a progressive plane wave

The dynamics of a charged particle in a relativistic strong electromagnetic plane wave propagating in a medium is studied. The problem is shown to be integrable when the wave propagates in vacuum. When it propagates in plasma, and when the full plasma response is considered, an exhaustive numerical work allows us to conclude that the problem is not integrable.     

Brownian motion of a charged particle in a magnetic field

We develop and numerically illustrate an exact solution of the multivariate, stochastic, differential equations that govern the velocity and position of a charged particle in a plane normal to a uniform, stationary, magnetic field. The equations self-consistently incorporate the Lorentz force into an Ornstein-Uhlenbeck collision model. Properties of the solution in the infinite dissipation limit are explored and the spectral energy density function is found     

光阱中布朗粒子动力学分析

通过对光阱中的布朗粒子进行动力学方程求解,由解的结果分析得到观测系统的性能要求．结果表明：光阱中布朗颗粒服从Boltzmann分布;对其运动的观测需要纳米量级的空间分辨率和毫秒量级的时间分辨率．     

Subharmonic excitation of the eigenmodes of charged particles in a Penning trap

When parametrically excited, a harmonic system reveals a nonlinear dynamical behaviour which is common to non-deterministic phenomena. The ion motion in a Penning trap -- which can be regarded as a system of harmonic oscillators -- offers the possibility to study anharmonic characteristics when perturbed by an external periodical driving force. In our experiment we excited an electron cloud stored in a Penning trap by applying an additional quadrupole r.f. field to the endcaps. We observed phenomena such as individual and center-of-mass oscillations of an electron cloud and fractional frequencies, so-called subharmonics, to the axial oscillation. The latter show a characteristic threshold behaviour. This phenomenon can be explained with the existence of a damping mechanism affecting the electron cloud; a minimum value of the excitation amplitude is required to overcome the damping. We could theoretically explain the observed phenomenon by numerically calculating the solutions of the damped differential Mathieu equation. This numerical analysis accounts for the fact that for a weak damping of the harmonic system we observed an even-odd-staggering of the the different orders of the subharmonics in the axial excitation spectrum.Received: 22 September 2003, Published online: 2 December 2003PACS: 52.27.Jt Nonneutral plasmas - 82.80.Qx Ion cyclotron resonance mass spectrometry     

On the non-radiating motion of a charged particle

The most general class of the electric and magnetic fields such that a charged particle moving in this field will not radiate is obtained. Apart from suitably orientated constant fields, it includes some special varying (but steady) fields.