Three-body forces and the trinucleons
International Nuclear Information System (INIS)
Friar, J.L.
1987-01-01
Three-body forces are discussed in the context of classical, atomic, solid-state and nuclear physics. The basic theoretical ingredients used in the construction of such forces are reviewed. Experimental evidence for three-nucleon forces and an overview of the three-nucleon bound states are presented. 53 refs., 9 figs
Three-body forces: a status report
International Nuclear Information System (INIS)
Coon, S.A.
1976-01-01
Real three-body forces due to meson exchange are distinguished from effective three-body interactions of a nuclear Hamiltonian. The long-range part of the real three-body force is proportional to the off-mass-shell sup(PI)N scattering amplitude. Its contribution to the binding energy of nuclear matter is quite dependent upon the treatment of correlations (due to the two-body potential) in the three-body wave function. A recent improvemrnt in the amplitude implies a very small contribution. But, a recent improvement in the treatment of correlations implies a large contribution. Work towards including both these improvements in a single calculation is in progress. (author)
Three-body ΛNN force due to Λ-Σ coupling
International Nuclear Information System (INIS)
Myint, Khin Swe; Akaishi, Yoshinori
2003-01-01
The ΛNN three - body force due to coherent Λ - Σ Coupling effect was derived from realistic Nijmegen model D potential. Repulsive and attractive three - body ΛNN forces were reconcilably accounted. For 5 He, within one - channel description, ΛNN force is largely repulsive and its origin comes from Pauli forbidden terms. Within two - channel description, attractive Pauli allowed terms exist and resulting three - body force is always attractive. Large attractive ΛNN force effect due to coherent Λ - Σ coupling effect is predicted in neutron - rich nuclei. The attractive coherent Λ - Σ coupling effect is largely enhanced at high density neutron matter. The attractive three - body ΛNN force effect is essential dynamics of Λ - Σ coupling while the repulsive Nogami three - body effect arises from Pauli forbidden diagrams. (Y. Kazumata)
Three-body unitary transformations, three-body forces, and trinucleon bound state properties
International Nuclear Information System (INIS)
Haftel, M.I.
1976-01-01
A three-body unitary transformation method for the study of three-body forces is presented. Starting with a three-body Hamiltonian with two-body forces, unitary transformations are introduced to generate Hamiltonians that have both two- and three-body forces. For cases of physical interest, the two-body forces of the altered Hamiltonians are phase equivalent (for two-body scattering) to the original and the three-body force vanishes when any interparticle distance is large. Specific examples are presented. Applications for studying the possible role of three-body forces in accounting for trinucleon bound state properties are examined. Calculations of the 3 He and 3 H charge form factors and Coulomb energy difference with hyperspherical radial transformations and with conventional N-N potentials are performed. The form factor calculations demonstrate how the proposed method can help obtain improved agreement with experiment by the introduction of appropriate three-body forces. Calculations of the Coulomb energy difference confirm previous estimates concerning charge symmetry breaking in the N-N interaction
Three-Body Nuclear Forces from a Matrix Model
Hashimoto, Koji
2010-01-01
We compute three-body nuclear forces at short distances by using the nuclear matrix model of holographic QCD proposed in our previous paper with P. Yi. We find that the three-body forces at short distances are repulsive for (a) aligned three neutrons with averaged spins, and (b) aligned proton-proton-neutron / proton-neutron-neutron. These indicate that in dense states of neutrons such as cores of neutron stars, or in Helium-3 / tritium nucleus, the repulsive forces are larger than the ones estimated from two-body forces only.
International Nuclear Information System (INIS)
Barford, Thomas; Birse, Michael C
2005-01-01
A distorted-wave version of the renormalization group is applied to scattering by an inverse-square potential and to three-body systems. In attractive three-body systems, the short-distance wavefunction satisfies a Schroedinger equation with an attractive inverse-square potential, as shown by Efimov. The resulting oscillatory behaviour controls the renormalization of the three-body interactions, with the renormalization-group flow tending to a limit cycle as the cut-off is lowered. The approach used here leads to single-valued potentials with discontinuities as the bound states are cut off. The perturbations around the cycle start with a marginal term whose effect is simply to change the phase of the short-distance oscillations, or the self-adjoint extension of the singular Hamiltonian. The full power counting in terms of the energy and two-body scattering length is constructed for short-range three-body forces
Three-body scattering problem in the fixed center approximation: The case of attraction
Energy Technology Data Exchange (ETDEWEB)
Kudryavtsev, Alexander E. [National Research Center Kurchatov Institute, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Gani, Vakhid A. [National Research Center Kurchatov Institute, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Romanov, Alexander I. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)
2016-12-15
We study the scattering of a light particle on a bound pair of heavy particles (e.g., the deuteron) within the fixed center approximation in the case of light-heavy attraction, solving the integral equation for the three-body Green's function both in the coordinate and in the momentum space. The results for the three-body scattering amplitude appear to be ambiguous -they depend on a single real parameter. This parameter may be fixed by a three-body input, e.g., the three-body scattering length. We also solve the integral equation for the three-body Green function in the momentum space, introducing a finite cut-off. We show that all three approaches are equivalent. We also discuss how our approach to the problem matches with the introduction of three-body contact interaction as done by other authors. (orig.)
Three-body force in the three-nucleon system
International Nuclear Information System (INIS)
Gibson, B.F.
1986-01-01
A brief summary of the symposium is presented. Three-nucleon force models are discussed, including the two-pion exchange potential, NN-ΔN coupled-channels model, and phenomenological parametrization. Relevant experimental data and model calculations are discussed including form factors, binding energies, charge radii, and charge density for 3 H and 3 He. A calculation of the EMC effect for 3 He is also made using Sasakawa's wave function and compared to experimental data obtained at SLAC. The paper ends with discussions of proton-deuteron scattering, investigations at intermediate energies, and QCD efforts to understand the three-body problem
Effect of three-body forces on the phase behavior of charged colloids
International Nuclear Information System (INIS)
Wu, J. Z.; Bratko, D.; Blanch, H. W.; Prausnitz, J. M.
2000-01-01
Statistical-thermodynamic theory for predicting the phase behavior of a colloidal solution requires the pair interaction potential between colloidal particles in solution. In practice, it is necessary to assume pairwise additivity for the potential of mean force between colloidal particles, but little is known concerning the validity of this assumption. This paper concerns interaction between small charged colloids, such as surfactant micelles or globular proteins, in electrolyte solutions and the multibody effect on phase behavior. Monte Carlo simulations for isolated colloidal triplets in equilateral configurations show that, while the three-body force is repulsive when the three particles are near contact, it becomes short-ranged attractive at further separations, contrary to a previous study where the triplet force is attractive at all separations. The three-body force arises mainly from hard-sphere collisions between colloids and small ions; it is most significant in solutions of monovalent salt at low concentration where charged colloids experience strong electrostatic interactions. To illustrate the effect of three-body forces on the phase behavior of charged colloids, we calculated the densities of coexisting phases using van der Waals-type theories for colloidal solutions and for crystals. For the conditions investigated in this work, even though the magnitude of the three-body force may be as large as 10% of the total force at small separations, three-body forces do not have a major effect on the densities of binary coexisting phases. However, coexisting densities calculated using Derjaguin-Landau-Verwey-Overbeek theory are much different from those calculated using our simulated potential of mean force. (c) 2000 American Institute of Physics
Three-body forces in p-shell nuclei
International Nuclear Information System (INIS)
Hees, A.G.M. van; Booten, J.G.L.; Glaudemans, P.W.M.
1990-01-01
Within the (0 + 1)ℎω shell-model space for p-shell nuclei we found that a schematic three-body interaction in addition to a translationally invariant two-body interaction leads to a strongly improved description of energy levels. The present three-body interaction is related to the Δ-isobar intermediate-state model of the two-pion exchange three-nucleon interaction. (orig.)
Folding model analysis of Λ binding energies and three-body ΛNN force
International Nuclear Information System (INIS)
Mian, M.; Rahman Khan, M.Z.
1988-02-01
Working within the framework of the folding model, we analyze the Λ binding energy data of light hypernuclei with effective two-body ΛN plus three-body ΛNN interaction. The two-body density for the core nucleus required for evaluating the three-body force contribution is obtained in terms of the centre of mass pair correlation. It is found that except for Λ 5 He the data are fairly well explained. The three-body force seems to account for the density dependence of the effective two-body ΛN interaction proposed earlier. (author). 13 refs, 2 tabs
Influence of effective three-body force on the spectroscopy of 19O
International Nuclear Information System (INIS)
Haung, W.; Song, H.; Wang, Z.; Kuo, T.T.S.
1983-01-01
The purpose of the present paper is to investigate the influence of effective three-body force on the spectroscopy of 19 O. The model space was chosen as the configuration space which consists of the j-j coupling states of three valence neutrons in the s-d shell. The effective interaction including two- and three-body forces was then derived in the framework of the folded diagram method (FDM). Besides two traditional three-body terms, there is another kind of three-body force, the folded one constructed with two two-body diagrams, in FDM. The G-matrix elements of soft core Reid force were used in the numerical calculations. In the case of lacking the G-matrix elements, we adopted the matrix elements of M-3Y force as the equivalents. The results show that the influence of the effective three-body forces on the spectrum of 19 O is not of importance, but the part coming from the folded three-body term is worth noting
Study on 16O in the alpha particle model using three-body forces
International Nuclear Information System (INIS)
Agrello, D.A.
1979-01-01
A study of the ground state of 16 O is made using an alpha particle model, all without internal structure, interacting through two-and three-body forces. Some nuclear properties of 16 O, such as binding energy and gaps, are also studied. (L.C.) [pt
Effect of three-body forces on the lattice dynamics of noble metals
Indian Academy of Sciences (India)
A simple method to generate an effective electron–ion interaction pseudopotential from the energy wave number characteristic obtained by ﬁrst principles calculations has been suggested. This effective potential has been used, in third order perturbation, to study the effect of three-body forces on the lattice dynamics of ...
Analytical equation of state with three-body forces: Application to noble gases
International Nuclear Information System (INIS)
Río, Fernando del; Díaz-Herrera, Enrique; Guzmán, Orlando; Moreno-Razo, José Antonio; Ramos, J. Eloy
2013-01-01
We developed an explicit equation of state (EOS) for small non polar molecules by means of an effective two-body potential. The average effect of three-body forces was incorporated as a perturbation, which results in rescaled values for the parameters of the two-body potential. These values replace the original ones in the EOS corresponding to the two-body interaction. We applied this procedure to the heavier noble gases and used a modified Kihara function with an effective Axilrod-Teller-Muto (ATM) term to represent the two- and three-body forces. We also performed molecular dynamics simulations with two- and three-body forces. There was good agreement between predicted, simulated, and experimental thermodynamic properties of neon, argon, krypton, and xenon, up to twice the critical density and up to five times the critical temperature. In order to achieve 1% accuracy of the pressure at liquid densities, the EOS must incorporate the effect of ATM forces. The ATM factor in the rescaled two-body energy is most important at temperatures around and lower than the critical one. Nonetheless, the rescaling of two-body diameter cannot be neglected at liquid-like densities even at high temperature. This methodology can be extended straightforwardly to deal with other two- and three-body potentials. It could also be used for other nonpolar substances where a spherical two-body potential is still a reasonable coarse-grain approximation
The Tucson-Melbourne Three-Body Force in a Translationally-Invariant Harmonic Oscillator Basis
Marsden, David; Navratil, Petr; Barrett, Bruce
2000-09-01
A translationally-invariant three-body basis set has been employed in shell model calculations on ^3H and ^3He including the Tucson-Melbourne form of the real nuclear three-body force. The basis consists of harmonic oscillators in Jacobi coordinates, explicitly avoiding the centre of mass drift problem in the calculations. The derivation of the three-body matrix elements and the results of large basis effective interaction shell model calculations will be presented. J. L. Friar, B. F. Gibson, G. L. Payne and S. A. Coon; Few Body Systems 5, 13 (1988) P. Navratil, G.P. Kamuntavicius and B.R. Barrett; Phys. Rev. C. 61, 044001 (2000)
Three-body forces for electrons by the S-matrix method
International Nuclear Information System (INIS)
Margaritelli, R.
1989-01-01
A electromagnetic three-body potential between eletrons is derived by the S-matrix method. This potential can be compared up to a certain point with other electromagnetic potentials (obtained by other methods) encountered in the literature. However, since the potential derived here is far more complete than others, this turns direct comparison with the potentials found in the literature somewhat difficult. These calculations allow a better understanding of the S-matrix method as applied to problems which involve the calculations of three-body nuclear forces (these calculations are performed in order to understand the 3 He form factor). Furthermore, these results enable us to decide between two discrepant works which derive the two-pion exchange three-body potential, both by the S-matrix method. (author) [pt
The three-body forces with two δ excitation and N+d scattering
International Nuclear Information System (INIS)
Uzu, Eizo; Koike, Yasuro; Yamaguchi, Masahiro; Kamada, Hiroyuki
2005-01-01
The differential cross section of 250 MeV N+d scattering was different from the results of Faddeev calculation. The possibility of δ excitation of two nucleons of deuteron in the initial state is considered and the degree of freedom of δδ excitation is applied to improve the three-body force effects. The system consisted of two nucleons, nucleon and δ particle, and two δparticles is called by NN, Nδ and δδ system, respectively. The first calculation was carried out by using AV14 potential as ordinary nuclear force and AV28 as interaction with Nδ and δδ as three-body. The results of calculation for 250 and 135 MeV N+d scattering showed no effect on the differential cross section but the large effect on the tensor resolving power. (S.Y.)
The baryonic spectrum in a constituent quark model including a three-body force
International Nuclear Information System (INIS)
Desplanques, B.; Gignoux, C.; Silvestre-Brac, B.; Gonzalez, P.; Navarro, J.; Noguera, S.
1992-01-01
We analyze, within a non-relativistic quark model, the low energy part of the baryonic spectrum in the octet and decuplet flavour representations. The relevance of a strong Coulomb potential is emphasized in order to explain its general features. The addition of a three-body force allows to solve the 'Roper puzzle', giving a consistent explanation to its relative position in the spectrum. (orig.)
International Nuclear Information System (INIS)
Zuo Wei; Lu Guangcheng; Li Zenghua; Luo Peiyan; Chinese Academy of Sciences, Beijing
2005-01-01
The finite temperature Brueckner-Hartree-Fock (FTBHF) approach is extended by introducing a microscopic three-body force. Within the extended approach, the three-body force effects on the equation of state of hot nuclear matter and its temperature dependence have been investigated. The critical properties of the liquid-gas phase transition of hot nuclear matter have been calculated. It is shown that the three-body force provides a repulsive contribution to the equation of state of hot nuclear matter. The repulsive effect of the three-body force becomes more pronounced as the density and temperature increase and consequently inclusion of the three-body force contribution in the calculation reduces the predicted critical temperature from about 16 MeV to about 13 MeV. By separating the contribution originated from the 2σ-exchange process coupled to the virtual excitation of a nucleon-antinucleon pair from the full three-body force, the connection between the three-body force effect and the relativistic correction from the Dirac-Brueckner-Hartree-Fock has been explored. It turns out that the contribution of the 2σ-N(N-bar) part is more repulsive than that of the full three-body force and the calculated critical temperature is about 11 MeV if only the 2σ-N(N-bar) component of the three-body force is included which is lower than the value obtained in the case of including the full three-body force and is close to the value predicted by the Dirac-Brueckner-Hartree-Fock (DBHF) approach. Our result provides a reasonable explanation for the discrepancy between the values of critical temperature predicted from the FTBHF approach including the three-body force and the DBHF approach. (authors)
Three-body correlations and conditional forces in suspensions of active hard disks
Härtel, Andreas; Richard, David; Speck, Thomas
2018-01-01
Self-propelled Brownian particles show rich out-of-equilibrium physics, for instance, the motility-induced phase separation (MIPS). While decades of studying the structure of liquids have established a deep understanding of passive systems, not much is known about correlations in active suspensions. In this work we derive an approximate analytic theory for three-body correlations and forces in systems of active Brownian disks starting from the many-body Smoluchowski equation. We use our theory to predict the conditional forces that act on a tagged particle and their dependence on the propulsion speed of self-propelled disks. We identify preferred directions of these forces in relation to the direction of propulsion and the positions of the surrounding particles. We further relate our theory to the effective swimming speed of the active disks, which is relevant for the physics of MIPS. To test and validate our theory, we additionally run particle-resolved computer simulations, for which we explicitly calculate the three-body forces. In this context, we discuss the modeling of active Brownian swimmers with nearly hard interaction potentials. We find very good agreement between our simulations and numerical solutions of our theory, especially for the nonequilibrium pair-distribution function. For our analytical results, we carefully discuss their range of validity in the context of the different levels of approximation we applied. This discussion allows us to study the individual contribution of particles to three-body forces and to the emerging structure. Thus, our work sheds light on the collective behavior, provides the basis for further studies of correlations in active suspensions, and makes a step towards an emerging liquid state theory.
Three-body forces in nuclear matter from intermediate Δ-states in three-nucleon clusters
International Nuclear Information System (INIS)
Kouki, T.; Smulter, L.E.W.; Green, A.M.
1976-10-01
The three-body force contribution in nuclear matter is treated as a three-nucleon cluster, in which one of the nucleons becomes, in an intermediate state, a Δ(1236). All exchange diagrams are calculated and found to significantly reduce the energy per particle from the direct graph. This is contrary to earlier estimates of the exchanges, using more approximate approaches. The resulting attractive contribution is rather small, -1.1 MeV at ksub(F)=1.4 fm -1 , but the roughly linear density dependence has a crucial effect on the saturation properties. The sensitivity of the results to the correlations used, and to the two-body force spin structure, is displayed. The energy per particle from clusters with three intermediate Δ's is also estimated. (author)
On contribution of three-body forces to Nd interaction at intermediate energies
International Nuclear Information System (INIS)
Uzikov, Yu.N.
2001-01-01
Available data on large-angle nucleon-deuteron elastic scattering Nd → dN below the pion threshold give a signal for three-body forces. There is a problem of separation of possible subtle aspects of these forces from off-shell effects in two-nucleon potentials. By considering the main mechanisms of the process Nd → dN, we show qualitatively that in the quasi-binary reaction N + d → (NN) + N with the final spin singlet NN-pair in the S-state the relative contribution of the 3N forces differs substantially from the elastic channel. It gives a new testing ground for the problem in question
Role of three-body forces in lattice dynamics of neodymium antimonide
International Nuclear Information System (INIS)
Gupta, H.N.; Kanti Chandra
1979-01-01
Recently the experimental phonon-dispersion curves of neodymium antimonide (NdSb) have been reported by Wakabayashi and Furrer (1976). These results have been analysed using an extended three-body force shell model (ESTM) in its nearest-neighbour version which provides a very good agreement for acoustic- and a reasonably good agreement for optical-branches of dispersion curves. This shows clearly the effect of three-body forces in this solid. The lack in degree of agreement in the optical branches may be ascribed to the presence of (i) zero Lyddane-Sachs-Teller (LST) splitting of zone-centre optical vibration frequencies (ωsub(Lo) and ωsub(To)) (ii) some anomalous wiggles in those branches. While the former is explained by setting Lundquist's effective charge parameter (esub(L)) equal to zero in the theory of ESTM, the later is expected to be explained satisfactorily by including free-electron screening effects in the theoretical framework of ESTM. (auth.)
Derivation of a pion-rho exchange three-body force and application to the trinucleon system
International Nuclear Information System (INIS)
Robillota, M.R.; Isidro Filho, M.P.
1982-12-01
The pion-rho exchange three-body force is derived by means of Lagrangians which are approximately invariant under chiral and gauge transformations. The leading contribution to the potential arises from a seagull diagram, which corresponds to forces that are dominantly repulsive and comparable to those due to the exchange of two pions. The qualitative features of the results are analysed by means of plots of the energy of the trinucleon system. (Author) [pt
Derivation of a pion-RHO exchange three-body force and application to the trinucleon system
International Nuclear Information System (INIS)
Robilotta, M.R.; Isidro Filho, M.P.
1984-01-01
The pion-rho exchange three-body force is derived by means of lagrangians which are approximately invariant under chiral and gauge transformations. The leading contribution to the potential arises from a seagull diagram, which corresponds to forces that are dominantly repulsive and comparable to those due to the exchange of two pions. The qualitative features of our results are analysed by means of plots of the energy of the trinucleon system. (orig.)
Messina, Riccardo; Antezza, Mauro
2014-05-01
We study the Casimir-Lifshitz force and the radiative heat transfer in a system consisting of three bodies held at three independent temperatures and immersed in a thermal environment, the whole system being in a stationary configuration out of thermal equilibrium. The theory we develop is valid for arbitrary bodies, i.e., for any set of temperatures, dielectric, and geometrical properties, and describes each body by means of its scattering operators. For the three-body system we provide a closed-form unified expression of the radiative heat transfer and of the Casimir-Lifshitz force (both in and out of thermal equilibrium). This expression is thus first applied to the case of three planar parallel slabs. In this context we discuss the nonadditivity of the force at thermal equilibrium, as well as the equilibrium temperature of the intermediate slab as a function of its position between two external slabs having different temperatures. Finally, we consider the force acting on an atom inside a planar cavity. We show that, differently from the equilibrium configuration, the absence of thermal equilibrium admits one or more positions of minima for the atomic potential. While the corresponding atomic potential depths are very small for typical ground-state atoms, they may become particularly relevant for Rydberg atoms, becoming a promising tool to produce an atomic trap.
Role of attractive forces in tapping tip force microscopy
DEFF Research Database (Denmark)
Kyhle, Anders; Sørensen, Alexis Hammer; Bohr, Jakob
1997-01-01
We present experimental and numerical results demonstrating the drastic influence of attractive forces on the behaviour of the atomic force microscope when operated in the resonant tapping tip mode in an ambient environment. It is often assumed that tapping is related to repulsive interaction...
Shukla-Eliasson attractive force: Revisited
Akbari-Moghanjoughi, M.; Akbari-Moghanjoughi
2013-04-01
By investigating the dielectric response of the Fermi-Dirac plasma in the linear limit and evaluating the electrostatic potential around the positive stationary test charge, we find that the Shukla-Eliasson attractive force is present for the plasma density range expected in the interiors of large planets for a wide range of plasma atomic number. This research, which is based on the generalized electron Fermi-momentum, further confirms the existence of the newly discovered Lennard-Jones-like attractive potential and its inevitable role in plasma crystallization in the cores of planets. Moreover, it is observed that the characteristics of the attractive potential are strongly sensitive to the variation of plasma density and composition. Current research can also have applications in the study of strong laser-matter interactions and inertially confined plasmas.
Fluids with highly directional attractive forces. III. Multiple attraction sites
International Nuclear Information System (INIS)
Wertheim, M.S.
1986-01-01
The authors derive a reformulation of statistical thermodynamics for fluids of molecules which interact by highly directional attraction. The molecular model consists of a repulsive core and several sites of very short-ranged attraction. The authors explore the relationship between graph cancellation in the fugacity expansion and three types of steric incompatibility between repulsive and attractive interactions involving several molecules. The steric effects are used to best advantage in a limited regrouping of bonds. This controls the density parameters which appear when articulation points are eliminated in the graphical representation. Each density parameter is a singlet density for a species consisting of molecules with a specified set of sites bonded. The densities satisfy subsidiary conditions of internal consistency. These conditions are equivalent to a minimization of the Helmholtz free energy A. Graphical expressions for A and for the pressure are derived. Analogs of the s-particle direct correlation functions and of the Ornstein-Zernike equation are found
Effects of repulsive three-body force in 12C + 12C scattering at 100A MeV
Directory of Open Access Journals (Sweden)
W.W. Qu
2015-12-01
Full Text Available The angular distribution of 12C + 12C scattering at an incident energy of 100A MeV has been measured. The elastic and inelastic scatterings in 12C to the excitation energies of up to ∼45 MeV were measured simultaneously for the first time with the high-resolution Grand Raiden spectrometer at the Research Center for Nuclear Physics (RCNP. The angular distributions of the elastic scattering to the ground state (01+ and inelastic scattering to the 4.44 MeV (21+ excited state were precisely obtained in the angular range of 1.0°–7.5° with a step of 0.1°. Additionally, the angular distribution was obtained for the sum of the cross sections for excitation energies above the 4.44 MeV state up to 11 MeV, which includes the 7.65 MeV (02+, 9.64 MeV (31−, and 10.30 MeV (22+ states, in addition to probably the simultaneous excitation of the 4.44 MeV state in the projectile and the target nuclei. Those combined data provide a means to study the effects of channel coupling on the elastic cross section. The observed angular distributions are compared with theoretical calculations based on three double-folding models with complex G-matrix interactions, the CEG07b, MPa, and ESC models. The importance of three-body repulsive forces included in the CEG07b and MPa models will be discussed.
Attractive and repulsive quantum forces from dimensionality of space
DEFF Research Database (Denmark)
Bialynicki-Birula, I.; Cirone, M.A.; Dahl, Jens Peder
2002-01-01
Two particles of identical mass attract and repel each other even when there exist no classical external forces and their average relative momentum vanishes. This quantum force depends crucially on the number of dimensions of space.......Two particles of identical mass attract and repel each other even when there exist no classical external forces and their average relative momentum vanishes. This quantum force depends crucially on the number of dimensions of space....
Effects of solute--solvent attractive forces on hydrophobic correlations
International Nuclear Information System (INIS)
Pratt, L.R.; Chandler, D.
1980-01-01
A theory is presented for the effect of slowly varying attractive forces on correlations between nonpolar solutes in dilute aqueous solution. We find that hydrophobic correlations are sensitive to relatively long range slowly varying interactions. Thus, it is possible to make qualitative changes in these correlations by introducing small changes in the attractive forces. Several model calculations are presented to illustrate these facts. The contributions of the Lennard-Jones attractive forces to the computer simulation results of Pangali, Rao, and Berne are calculated. For this case it is found that the potential of mean force between spherical nonpolar solutes is hardly affected by inclusion of attractive forces. However, the osmotic second virial coefficient is dominated by the contributions of the attractive forces. For spherical solutes which provide a reasonable model for the methane molecule, inclusion of attractive forces produces a qualitative change in the methane--methane potential of mean force. The connection between these effects of slowly varying attractive forces and the enthalpic part of Ben-Naim's deltaA/sup H/I is discussed
International Nuclear Information System (INIS)
Musielak, Z E; Quarles, B
2014-01-01
The three-body problem, which describes three masses interacting through Newtonian gravity without any restrictions imposed on the initial positions and velocities of these masses, has attracted the attention of many scientists for more than 300 years. In this paper, we present a review of the three-body problem in the context of both historical and modern developments. We describe the general and restricted (circular and elliptic) three-body problems, different analytical and numerical methods of finding solutions, methods for performing stability analysis and searching for periodic orbits and resonances. We apply the results to some interesting problems of celestial mechanics. We also provide a brief presentation of the general and restricted relativistic three-body problems, and discuss their astronomical applications. (review article)
The similarity of attractive and repulsive forces on a lattice
Mirahmadi, Marjan-S.; Fatollahi, Amir H.; Khorrami, Mohammad
2015-07-01
On a lattice, as the momentum space is compact, the kinetic energy is bounded not only from below but also from above. It is shown that this somehow removes the distinction between repulsive and attractive forces. In particular, it is seen that a region with attractive force would appear forbidden for states with energies higher than a certain value, while repulsive forces could develop bound-states. An explicit transformation is introduced which transforms the spectrum of a system corresponding to a repulsive force, to that of a similar system corresponding to an attractive force. Explicit numerical examples are presented for discrete energies of bound-states of a particle experiencing repulsive force by a piecewise constant potential. Finally, the parameters of a specific one-dimensional (1D) translationally invariant system on continuum are tuned so that the energy of the system resembles the kinetic energy of a system on a 1D lattice. In particular, the parameters are tuned so that while the width of the first energy band and its position are kept finite, the gap between the first energy band and the next energy band goes to infinity, so that effectively only the first energy band is relevant.
Fluids with highly directional attractive forces. IV. Equilibrium polymerization
International Nuclear Information System (INIS)
Wertheim, M.S.
1986-01-01
The author investigates approximation methods for systems of molecules interacting by core repulsion and highly directional attraction due to several attraction sites. The force model chosen imitates a chemical bond by providing for bond saturation when binding occurs. The dense fluid is an equilibrium mixture of s-mers with mutual repulsion. The author uses a previously derived reformulation of statistical thermodynamics in which the particle species are monomeric units with a specified set of attraction sites bonded. Thermodynamic perturbation theory (TPT) and integral equations of two types are derived. The use of TPT is illustrated by explicit calculation for a molecular model with two attraction sites capable of forming chain and ring polymers. Successes and defects of TPT are discussed. The integral equations for pair correlations between particles of specified bonding include calculation of self-consistent densities of species. Methods of calculating thermodynamic properties from the solutions of integral equations are given
Energy Technology Data Exchange (ETDEWEB)
Penninckx-Sans, A.
1995-07-10
The attractive forces effect is particularly interesting at the proximity of a critical point. In a liquid system, there are two kinds of attractive forces in presence : the forces bound to the solution volume and those generated by the presence of the solution surface or by a solution interface. In the first case, the attractive forces are the more important as the system is in a critical field. For this study, the selected example is a polymer solution in a two solvents mixture. A formulation in terms of way integrals as part of statistical physics has lead us to find again some known results on the polymer chain conformation in the presence of two solvents (collapse of the polymer on itself) far from the critical point and to extend these results to the critical field. In the case of attractive forces created by the surface in some critical systems (polymer of infinite size in solution and binary mixture near the de mixture point), the adsorption profile created by the attraction of one specie by the surface, follows a scale law. The optical methods usually used for the study of these systems do not give characteristic sign of concentration profile in power law. In the case where the interaction potential between radiation and matter is attractive, the reflectivity gives a separate mark of the existence of the scale law in the form of a resonance. After some theoretical forecasts, the author has used this method on the binary mixture methanol-cyclohexane in order to reveal experimentally a reflectivity pseudo-discontinuity and then the existence of the power law in the critical adsorption profile. (O.L.). 69 refs., 60 tabs.
Directory of Open Access Journals (Sweden)
P. P. Hallan
2008-01-01
Full Text Available The effect of perturbations in Coriolis and cetrifugal forces on the nonlinear stability of the equilibrium point of the Robe's (1977 restricted circular three-body problem has been studied when the density parameter K is zero. By applying Kolmogorov-Arnold-Moser (KAM theory, it has been found that the equilibrium point is stable for all mass ratios μ in the range of linear stability 8/9+(2/3((43/25ϵ1−(10/3ϵ<μ<1, where ϵ and ϵ1 are, respectively, the perturbations in Coriolis and centrifugal forces, except for five mass ratios μ1=0.93711086−1.12983217ϵ+1.50202694ϵ1, μ2 = 0.9672922−0.5542091ϵ+ 1.2443968ϵ1, μ3=0.9459503−0.70458206ϵ+ 1.28436549ϵ1, μ4=0.9660792−0.30152273ϵ + 1.11684064ϵ1, μ5=0.893981−2.37971679ϵ + 1.22385421ϵ1, where the theory is not applicable.
International Nuclear Information System (INIS)
Amado, R.D.
1975-01-01
An overview of the formal theory of the three-body problem as it has developed in the past twelve years is given. The formal structure of the theory, some of the techniques that have developed for handling the theory, and some results on how general quantum mechanical principles structure the results, are presented. The discussion is held entirely in the context of non-relativistic quantum mechanics with short-range forces. In this presentation the main outline of the theory is stressed, often at the expense of mathematical rigour [pt
The self-consistent field model for Fermi systems with account of three-body interactions
Directory of Open Access Journals (Sweden)
Yu.M. Poluektov
2015-12-01
Full Text Available On the basis of a microscopic model of self-consistent field, the thermodynamics of the many-particle Fermi system at finite temperatures with account of three-body interactions is built and the quasiparticle equations of motion are obtained. It is shown that the delta-like three-body interaction gives no contribution into the self-consistent field, and the description of three-body forces requires their nonlocality to be taken into account. The spatially uniform system is considered in detail, and on the basis of the developed microscopic approach general formulas are derived for the fermion's effective mass and the system's equation of state with account of contribution from three-body forces. The effective mass and pressure are numerically calculated for the potential of "semi-transparent sphere" type at zero temperature. Expansions of the effective mass and pressure in powers of density are obtained. It is shown that, with account of only pair forces, the interaction of repulsive character reduces the quasiparticle effective mass relative to the mass of a free particle, and the attractive interaction raises the effective mass. The question of thermodynamic stability of the Fermi system is considered and the three-body repulsive interaction is shown to extend the region of stability of the system with the interparticle pair attraction. The quasiparticle energy spectrum is calculated with account of three-body forces.
Attractive and Repulsive Forces on Particles in Oscillatory Flow
Agarwal, Siddhansh; Rallabandi, Bhargav; Raju, David; Thameem, Raqeeb; Hilgenfeldt, Sascha
2016-11-01
A large class of oscillating flows gives rise to rectified streaming motion of the fluid. It has recently been shown that particle transport in such flows, excited by bubbles oscillating at ultrasound frequencies, leads to differential displacement and efficient sorting of microparticles by size. We derive a general expression for the instantaneous radial force experienced by a small spherical particle in the vicinity of an oscillating interface, and generalize the radial projection of the Maxey-Riley equation to include this effect. Varying relevant system parameters, we show that the net effect on the particle can be either an attraction to or a repulsion from the bubble surface, depending in particular on the particle size and the particle/fluid density contrast. We demonstrate that these predictions are in agreement with a variety of experiments.
Coherent Destruction of Tunneling of Bosons with Effective Three-Body Interactions
International Nuclear Information System (INIS)
Niu Zhen-Xia; Yu Zi-Fa; Xue Ju-Kui
2015-01-01
The tunneling dynamics of dilute boson gases with three-body interactions in a periodically driven double wells are investigated both theoretically and numerically. In our findings, when the system is with only repulsive two-body interactions or only three-body interactions, the tunneling will be suppressed; while in the case of the coupling between two- and three-body interactions, the tunneling can be either suppressed or enhanced. Particularly, when attractive three-body interactions are twice large as repulsive two-body interactions, CDT occurs at isolated points of driving force, which is similar to the linear case. Considering different interaction, the system can experience different transformation from coherent tunneling to coherent destruction of tunneling (CDT). The quasi-energy of the system as the function of the periodically driving force shows a triangular structure, which provides a deep insight into the tunneling dynamics of the system. (paper)
Role of attractive forces in determining the equilibrium structure and dynamics of simple liquids
DEFF Research Database (Denmark)
Toxværd, Søren
2015-01-01
Molecular Dynamics simulations of a Lennard-Jones system with different range of attraction show that the attractive forces modify the radial distribution of the particles. For condensed liquids only, the forces within the the first coordination shell (FCS) are important, but for gases and moderate...... condensed fluids, even the attractive forces outside the FCS play a role. The changes in the distribution caused by neglecting the attractive forces, lead to a too high pressure. The weak long-range attractions damp the dynamics and the diffusion of the particles in gas-, super critical fluid- and in liquid...
Laws of attraction: from perceptual forces to conceptual similarity.
Ziemkiewicz, Caroline; Kosara, Robert
2010-01-01
Many of the pressing questions in information visualization deal with how exactly a user reads a collection of visual marks as information about relationships between entities. Previous research has suggested that people see parts of a visualization as objects, and may metaphorically interpret apparent physical relationships between these objects as suggestive of data relationships. We explored this hypothesis in detail in a series of user experiments. Inspired by the concept of implied dynamics in psychology, we first studied whether perceived gravity acting on a mark in a scatterplot can lead to errors in a participant's recall of the mark's position. The results of this study suggested that such position errors exist, but may be more strongly influenced by attraction between marks. We hypothesized that such apparent attraction may be influenced by elements used to suggest relationship between objects, such as connecting lines, grouping elements, and visual similarity. We further studied what visual elements are most likely to cause this attraction effect, and whether the elements that best predicted attraction errors were also those which suggested conceptual relationships most strongly. Our findings show a correlation between attraction errors and intuitions about relatedness, pointing towards a possible mechanism by which the perception of visual marks becomes an interpretation of data relationships.
Attractive forces in microporous carbon electrodes for capacitive deionization
Biesheuvel, P.M.; Porada, S.; Levi, M.; Bazant, M.Z.
2014-01-01
The recently developed modified Donnan (mD) model provides a simple and useful description of the electrical double layer in microporous carbon electrodes, suitable for incorporation in porous electrode theory. By postulating an attractive excess chemical potential for each ion in the micropores
International Nuclear Information System (INIS)
Yang, W M; Chao, X X; Bian, X B; Liu, P; Feng, Y; Zhang, P X; Zhou, L
2003-01-01
The levitation forces between a single-domain YBCO bulk and several magnets of different sizes have been measured at 77 K to investigate the effect of the magnet size on the levitation force. It is found that the levitation force reaches a largest (peak) value when the size of the magnet approaches that of the superconductor when the other conditions are fixed. The absolute maximum attractive force (in the field-cooled state) increases with the increasing of the magnet size, and is saturated when the magnet size approaches that of the superconductor. The maximum attractive force in the field-cooled (FC) state is much higher than that of the maximum attractive force in the zero field-cooled (ZFC) state. The results indicate that the effects of magnetic field distribution on the levitation force have to be considered during the designing and manufacturing of superconducting devices
Marchal, Christian
1990-01-01
Recent research on the theory of perturbations, the analytical approach and the quantitative analysis of the three-body problem have reached a high degree of perfection. The use of electronics has aided developments in quantitative analysis and has helped to disclose the extreme complexity of the set of solutions. This accelerated progress has given new orientation and impetus to the qualitative analysis that is so complementary to the quantitative analysis. The book begins with the various formulations of the three-body problem, the main classical results and the important questions and conje
Microscopic Theory for the Role of Attractive Forces in the Dynamics of Supercooled Liquids.
Dell, Zachary E; Schweizer, Kenneth S
2015-11-13
We formulate a microscopic, no adjustable parameter, theory of activated relaxation in supercooled liquids directly in terms of the repulsive and attractive forces within the framework of pair correlations. Under isochoric conditions, attractive forces can nonperturbatively modify slow dynamics, but at high enough density their influence vanishes. Under isobaric conditions, attractive forces play a minor role. High temperature apparent Arrhenius behavior and density-temperature scaling are predicted. Our results are consistent with recent isochoric simulations and isobaric experiments on a deeply supercooled molecular liquid. The approach can be generalized to treat colloidal gelation and glass melting, and other soft matter slow dynamics problems.
Coulomb effects in deuteron stripping reactions as a three-body problem
International Nuclear Information System (INIS)
Osman, A.
1981-08-01
Deuteron stripping nuclear reactions are reconsidered as a three-body problem. The Coulomb effects between the proton and the target nucleus are investigated. The mathematical formalism introduces three-body integral equations which can be exactly calculated for such simple models. These coupled integral equations suitably include the Coulomb effects due to replusive or attractive Coulomb potential. Numerical calculations of the differential cross-sections of the reactions 28 Si(d,p) 29 Si and 40 Ca(d,p) 41 Ca are carried out showing the importance of the Coulomb effects. The angular distributions of these reactions are theoretically calculated and fitted to the experimental data. From this fitting, reasonable spectroscopic factors are obtained. Inclusion of Coulomb force in the three-body model are found to improve the results by a percentage of about 6.826%. (author)
Indian Academy of Sciences (India)
. We have used the CD-Bonn potential-based realistic CWG [10] and the empirical ..... In another experiment, delayed γ-ray cascades, originating from the decay of isomeric .... 7/2 partition contributing ≃79–80% in SMPN/CWG3M calculations.
Attractive non-DLVO forces induced by adsorption of monovalent organic ions.
Smith, Alexander M; Maroni, Plinio; Borkovec, Michal
2017-12-20
Direct force measurements between negatively charged colloidal particles were carried out using an atomic force microscope (AFM) in aqueous solutions containing monovalent organic cations, namely tetraphenylarsonium (Ph 4 As + ), 1-hexyl-3-methylimidazolium (HMIM + ), and 1-octyl-3-methylimidazolium (OMIM + ). These ions adsorb to the particle surface, and induce a charge reversal. The forces become attractive at the charge neutralization point, but they are stronger than van der Waals forces. This additional and unexpected attraction decays exponentially with a decay length of a few nanometers, and is strikingly similar to the one previously observed in the presence of multivalent ions. This attractive force probably originates from coupled spontaneous charge fluctuations on the respective surfaces as initially suggested by Kirkwood and Shumaker.
International Nuclear Information System (INIS)
Qiu Kang; Tang Jun; Luo Jin-Ming; Ma Jun
2013-01-01
The cytosolic calcium system is inhomogenous because of the discrete and random distribution of ion channels on the ER membrane. It is well known that the spiral tip can be pinned by the heterogenous area, and the field can detach the spiral from the heterogeneity. We use the adventive field to counteract the attractive force exerting on the calcium spiral wave by the heterogeneity, then the strength of the adventive field is used to quantify the attractive force indirectly. Two factors determining the attractive force are studied. It is found that: (1) the attractive force sharply increases with size of the heterogeneity for small-size heterogeneity, whereas the force increases to a saturated value for large-size heterogeneity; (2) for large-size heterogeneity, the force almost remains constant unless the level of the heterogeneity vanishes, the force decreases to zero linearly and sharply, and for small-size heterogeneity, the force decreases successively with the level of the heterogeneity. Furthermore, it is found that the forces exist only when the spiral tip is very close to the heterogenous area. Our study may shed some light on the control or suppression of the calcium spiral wave
Evaluation of the attractive force of different types of new-generation magnetic attachment systems.
Akin, Hakan; Coskun, M Emre; Akin, E Gulsah; Ozdemir, A Kemal
2011-03-01
Rare earth magnets have been used in prosthodontics, but their tendency for corrosion in the oral cavity and insufficient attractive forces limit long-term clinical application. The purpose of this study was to evaluate the attractive force of different types of new-generation magnetic attachment systems. The attractive force of the neodymium-iron-boron (Nd-Fe-B) and samarium-cobalt (Sm-Co) magnetic attachment systems, including closed-field (Hilop and Hicorex) and open-field (Dyna and Steco) systems, was measured in a universal testing machine (n=5). The data were statistically evaluated with 1-way ANOVA and post hoc Tukey-Kramer multiple comparison test (α=.05). The closed-field systems exhibited greater (Pattractive force than the open-field systems. Moreover, there was a statistically significant difference in attractive force between Nd-Fe-B and Sm-Co magnets (Pattractive force was found with the Hilop system (9.2 N), and the lowest force was found with the Steco system (2.3 N). The new generation of Nd-Fe-B closed-field magnets, along with improved technology, provides sufficient denture retention for clinical application. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.
Light-induced attractive force between two metal bodies separated by a subwavelength slit
International Nuclear Information System (INIS)
Nesterov, Vladimir; Frumin, Leonid
2011-01-01
A novel light-induced attractive force which acts as a force with negative light pressure has been revealed. The force arises by the interaction of plasmon polaritons which are excited at the surface of metal when a transverse magnetic mode propagates through a subwavelength slit between two metal bodies. The estimation of the repulsive force acting on the metal walls of the slit in the case of subwavelength TE mode propagation along the slit is presented. The explicit analytical expressions of light-induced forces between two macroscopic metal bodies or films separated by a subwavelength slit have been derived. These forces could be used to manipulate metallic macro-, micro- and nano-objects in vacuum or in a dielectric medium. Estimations of these light-induced forces show that the forces are sufficient for measurements and practical applications
A study on the changes in attractive force of magnetic attachments for overdenture.
Leem, Han-Wool; Cho, In-Ho; Lee, Jong-Hyuk; Choi, Yu-Sung
2016-02-01
Although magnetic attachment is used frequently for overdenture, it is reported that attractive force can be decreased by abrasion and corrosion. The purpose of this study was to establish the clinical basis about considerations and long term prognosis of overdenture using magnetic attachments by investigating the change in attractive force of magnetic attachment applied to the patients. Among the patients treated with overdenture using magnetic attachments in Dankook University Dental Hospital, attractive force records of 61 magnetic attachments of 20 subjects who re-visited from July 2013 to June 2014 were analyzed. Dental magnet tester (Aichi Micro Intelligent Co., Aichi, Japan) was used for measurement. The magnetic attachments used in this study were Magfit IP-B Flat, Magfit DX400, Magfit DX600 and Magfit DX800 (Aichi Steel Co., Aichi, Japan) filled with Neodymium (NdFeB), a rare-earth magnet. Reduction ratio of attractive force had no significant correlation with conditional variables to which attachments were applied, and was higher when the maintenance period was longer (Pattractive force was significantly higher in the subject group in which attachments were used over 9 years than within 9 years (PAttractive force of magnetic attachment is maintained regardless of conditional variables and reduction ratio increased as the maintenance period became longer. Further study on adhesive material, attachment method and design improvement to prevent detachment of magnetic attachment is needed.
Molecular Theory and the Effects of Solute Attractive Forces on Hydrophobic Interactions.
Chaudhari, Mangesh I; Rempe, Susan B; Asthagiri, D; Tan, L; Pratt, L R
2016-03-03
The role of solute attractive forces on hydrophobic interactions is studied by coordinated development of theory and simulation results for Ar atoms in water. We present a concise derivation of the local molecular field (LMF) theory for the effects of solute attractive forces on hydrophobic interactions, a derivation that clarifies the close relation of LMF theory to the EXP approximation applied to this problem long ago. The simulation results show that change from purely repulsive atomic solute interactions to include realistic attractive interactions diminishes the strength of hydrophobic bonds. For the Ar-Ar rdfs considered pointwise, the numerical results for the effects of solute attractive forces on hydrophobic interactions are opposite in sign and larger in magnitude than predicted by LMF theory. That comparison is discussed from the point of view of quasichemical theory, and it is suggested that the first reason for this difference is the incomplete evaluation within LMF theory of the hydration energy of the Ar pair. With a recent suggestion for the system-size extrapolation of the required correlation function integrals, the Ar-Ar rdfs permit evaluation of osmotic second virial coefficients B2. Those B2's also show that incorporation of attractive interactions leads to more positive (repulsive) values. With attractive interactions in play, B2 can change from positive to negative values with increasing temperatures. This is consistent with the puzzling suggestions of decades ago that B2 ≈ 0 for intermediate cases of temperature or solute size. In all cases here, B2 becomes more attractive with increasing temperature.
Precise numerical results for limit cycles in the quantum three-body problem
International Nuclear Information System (INIS)
Mohr, R.F.; Furnstahl, R.J.; Hammer, H.-W.; Perry, R.J.; Wilson, K.G.
2006-01-01
The study of the three-body problem with short-range attractive two-body forces has a rich history going back to the 1930s. Recent applications of effective field theory methods to atomic and nuclear physics have produced a much improved understanding of this problem, and we elucidate some of the issues using renormalization group ideas applied to precise nonperturbative calculations. These calculations provide 11-12 digits of precision for the binding energies in the infinite cutoff limit. The method starts with this limit as an approximation to an effective theory and allows cutoff dependence to be systematically computed as an expansion in powers of inverse cutoffs and logarithms of the cutoff. Renormalization of three-body bound states requires a short range three-body interaction, with a coupling that is governed by a precisely mapped limit cycle of the renormalization group. Additional three-body irrelevant interactions must be determined to control subleading dependence on the cutoff and this control is essential for an effective field theory since the continuum limit is not likely to match physical systems (e.g., few-nucleon bound and scattering states at low energy). Leading order calculations precise to 11-12 digits allow clear identification of subleading corrections, but these corrections have not been computed
Three-body calculation of Be double-hypernuclei
Indian Academy of Sciences (India)
Energy levels and bond energy of the double- hypernucleus are calculated by considering two- and three-cluster interactions. Interactions between constituent particles are contact interactions for reproducing the low binding energy of nuclei. The effective action is constructed to involve three-body forces. In this paper ...
International Nuclear Information System (INIS)
George, S.M.; Harris, C.B.
1982-01-01
The dependence of inhomogeneous vibrational linewidth broadening on attractive forces form slowly varying local liquid number densities is examined. The recently developed Schweizer--Chandler theory of vibrational dephasing is used to compute absolute inhomogeneous broadening linewidths. The computed linewidths are compared to measured inhomogeneous broadening linewidths determined using picosecond vibrational dephasing experiments. There is a similarity between correlations of the Schweizer--Chandler and George--Auweter--Harris predicted inhomogeneous broadening linewidths and the measured inhomogeneous broadening linewidths. For the methyl stretches under investigation, this correspondence suggests that the width of the number density distribution in the liquid determines the relative inhomogeneous broadening magnitudes
Fokker-type dynamics with three-body correlations
International Nuclear Information System (INIS)
Salas, A.; Sanchez-Ron, J.M.
1981-01-01
Dynamical systems of N point particles without internal degrees of freedom are studied. Their equations of motion are derived from a Fokker-type variational principle with n-body correlations (n = 2,3,...,N), with special emphasis on the case n = 3. The distinction between n-body correlation and n-body effective force is analyzed in detail, with the help of an example. Maximal sets of independent three-body Poincare-invariant scalars are given. An example of three-body correlation formally similar to the usual two-body long-range scalar correlation is given and discussed. (author)
A wormlike chain model of forced desorption of a polymer adsorbed on an attractive wall
International Nuclear Information System (INIS)
Lam, Pui-Man; Zhen, Yi
2014-01-01
Forced desorption of a semiflexible polymer chain on a solid substrate is theoretically investigated. The pulling force versus displacement is studied for varying adsorption energy ε and persistence length P. It is found that the relationships between pulling force and cantilever displacement show a series of characteristic force spikes at different persistence lengths P. These force spikes become more pronounced but the average magnitude of this force decreases as P grows. Our results are of relevance to the forced desorption of DNA on an attractive wall in single-molecule pulling experiments. (paper)
Lee, Dominic J O'
2015-04-15
Dual mechanical braiding experiments provide a useful tool with which to investigate the nature of interactions between rod-like molecules, for instance actin and DNA. In conditions close to molecular condensation, one would expect an appearance of a local minimum in the interaction potential between the two molecules. We investigate this situation, introducing an attractive component into the interaction potential, using a model developed for describing such experiments. We consider both attractive interactions that do not depend on molecular structure and those which depend on a DNA-like helix structure. In braiding experiments, an attractive term may lead to certain effects. A local minimum may cause molecules to collapse from a loosely braided configuration into a tight one, occurring at a critical value of the moment applied about the axis of the braid. For a fixed number of braid pitches, this may lead to coexistence between the two braiding states, tight and loose. Coexistence implies certain proportions of the braid are in each state, their relative size depending on the number of braid pitches. This manifests itself as a linear dependence in numerically calculated quantities as functions of the number of braid pitches. Also, in the collapsed state, the braid radius stays roughly constant. Furthermore, if the attractive interaction is helix dependent, the left-right handed braid symmetry is broken. For a DNA like charge distribution, using the Kornyshev-Leikin interaction model, our results suggest that significant braid collapse and coexistence only occurs for left handed braids. Regardless of the interaction model, the study highlights the possible qualitative physics of braid collapse and coexistence; and the role helix specific forces might play, if important. The model could be used to connect other microscopic theories of interaction with braiding experiments.
International Nuclear Information System (INIS)
Lee, Dominic J
2015-01-01
Dual mechanical braiding experiments provide a useful tool with which to investigate the nature of interactions between rod-like molecules, for instance actin and DNA. In conditions close to molecular condensation, one would expect an appearance of a local minimum in the interaction potential between the two molecules. We investigate this situation, introducing an attractive component into the interaction potential, using a model developed for describing such experiments. We consider both attractive interactions that do not depend on molecular structure and those which depend on a DNA-like helix structure. In braiding experiments, an attractive term may lead to certain effects. A local minimum may cause molecules to collapse from a loosely braided configuration into a tight one, occurring at a critical value of the moment applied about the axis of the braid. For a fixed number of braid pitches, this may lead to coexistence between the two braiding states, tight and loose. Coexistence implies certain proportions of the braid are in each state, their relative size depending on the number of braid pitches. This manifests itself as a linear dependence in numerically calculated quantities as functions of the number of braid pitches. Also, in the collapsed state, the braid radius stays roughly constant. Furthermore, if the attractive interaction is helix dependent, the left-right handed braid symmetry is broken. For a DNA like charge distribution, using the Kornyshev–Leikin interaction model, our results suggest that significant braid collapse and coexistence only occurs for left handed braids. Regardless of the interaction model, the study highlights the possible qualitative physics of braid collapse and coexistence; and the role helix specific forces might play, if important. The model could be used to connect other microscopic theories of interaction with braiding experiments. (paper)
Sun, Zhelin; Wang, Deli; Xiang, Jie
2014-11-25
Spontaneous attractions between free-standing nanostructures have often caused adhesion or stiction that affects a wide range of nanoscale devices, particularly nano/microelectromechanical systems. Previous understandings of the attraction mechanisms have included capillary force, van der Waals/Casimir forces, and surface polar charges. However, none of these mechanisms universally applies to simple semiconductor structures such as silicon nanowire arrays that often exhibit bunching or adhesions. Here we propose a simple capacitive force model to quantitatively study the universal spontaneous attraction that often causes stiction among semiconductor or metallic nanostructures such as vertical nanowire arrays with inevitably nonuniform size variations due to fabrication. When nanostructures are uniform in size, they share the same substrate potential. The presence of slight size differences will break the symmetry in the capacitive network formed between the nanowires, substrate, and their environment, giving rise to electrostatic attraction forces due to the relative potential difference between neighboring wires. Our model is experimentally verified using arrays of vertical silicon nanowire pairs with varied spacing, diameter, and size differences. Threshold nanowire spacing, diameter, or size difference between the nearest neighbors has been identified beyond which the nanowires start to exhibit spontaneous attraction that leads to bridging when electrostatic forces overcome elastic restoration forces. This work illustrates a universal understanding of spontaneous attraction that will impact the design, fabrication, and reliable operation of nanoscale devices and systems.
Three-body unitarity with isobars revisited
Energy Technology Data Exchange (ETDEWEB)
Mai, M.; Hu, B. [The George Washington University, Washington, DC (United States); Doering, M. [The George Washington University, Washington, DC (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Pilloni, A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Szczepaniak, A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Indiana University, Center for Exploration of Energy and Matter, Bloomington, IN (United States); Indiana University, Physics Department, Bloomington, IN (United States)
2017-09-15
The particle exchange model of hadron interactions can be used to describe three-body scattering under the isobar assumption. In this study we start from the 3 → 3 scattering amplitude for spinless particles, which contains an isobar-spectator scattering amplitude. Using a Bethe-Salpeter Ansatz for the latter, we derive a relativistic three-dimensional scattering equation that manifestly fulfills three-body unitarity and two-body unitarity for the sub-amplitudes. This property holds for energies above breakup and also in the presence of resonances in the sub-amplitudes. (orig.)
Lavine method applied to three body problems
International Nuclear Information System (INIS)
Mourre, Eric.
1975-09-01
The methods presently proposed for the three body problem in quantum mechanics, using the Faddeev approach for proving the asymptotic completeness, come up against the presence of new singularities when the potentials considered v(α)(x(α)) for two-particle interactions decay less rapidly than /x(α)/ -2 ; and also when trials are made for solving the problem with a representation space whose dimension for a particle is lower than three. A method is given that allows the mathematical approach to be extended to three body problem, in spite of singularities. Applications are given [fr
Canonical three-body angular basis
International Nuclear Information System (INIS)
Matveenko, A.V.
2001-01-01
Three-body problems are basic for the quantum mechanics of molecular, atomic, or nuclear systems. We demonstrate that their variational solution for rotational states can be greatly simplified. A special choice of coordinates (hyperspherical) and of the kinematics (body-fixed coordinate frame) allows one to choose basis functions in a form that makes the angular coupling trivial. (author)
Bonitz, M.; Pehlke, E.; Schoof, T.
2013-03-01
This is the last of a series of three papers. In the first [Phys. Rev. E10.1103/PhysRevE.87.033105 87, 033105 (2013)], the same authors presented a critical analysis of the prediction of “novel attractive forces” between protons in dense hydrogen put forward by Shukla and Eliasson in a recent Letter [Phys. Rev. Lett.10.1103/PhysRevLett.108.165007 108, 165007 (2012)]. Based on ab initio density functional theory (DFT) calculations and general considerations, it was shown that no such force exists. In the second of the three papers [Phys. Rev. E10.1103/PhysRevE.87.037101 87, 037101 (2013)], Shukla, Eliasson, and Akbari-Moghanjoughi (SEA) rejected this analysis. SEA did not discuss our arguments but claimed that the discrepancy between their quantum hydrodynamic model (QHD) and DFT is due to a failure of the latter. It is the purpose of the present Reply to demonstrate that this claim is incorrect because DFT is more accurate than QHD, by construction.
Dobrivojević, Gordana
2013-01-01
Aims: The aim of this article is to come to the conclusion whether Porter’s five forces model can be adjusted for the purpose of assessing competitive environment of the tourist destination, in order to attract Tourism Foreign Direct Investments (TFDI), and use it as such as an alternative method for comprehension and enhancement of competitive advantage. Study design: Research paper. Methodology: The research relies on the well-known Porter’s five forces, which the author adjusted and applie...
Phelan, Angie; Petocz, Peter; Walsh, William; Darendeliler, M Ali
2012-11-01
The demand for clear sequential aligner therapy has increased dramatically in recent years. An improved system utilising small neodymium-iron-boron (NdFeB) magnetic attachments has been proposed to enhance appliance capabilities. The aim of the investigation was to analyse the force system diagrams produced by small attracting NdFeB magnets to determine, 1) whether the force levels were sufficient to induce tooth movement, 2) the effect of magnet morphology on force characteristics and, 3) the most appropriate magnet dimensions that could be utilised for this application. Twenty-nine NdFeB rectangular magnets of varying dimensions were tested. A Mach-1 universal testing machine (Biosyntech Inc, Quebec, Canada) was used to measure the attractive force of pairs of magnets. Measurements commenced with a magnetic pair in contact and subsequently vertically separated a distance of 10 mm at a speed of 12 mm/minute. For all magnetic configurations four repeat measurements were performed on five magnetic pairs of the same size. The force-distance diagrams for all magnet configurations demonstrated a dramatic decrease in force with increasing magnet separation. Rather than a suggested inverse square law, the experimental data followed an inverse fourth law when an offset determined by a regression analysis was applied to the distance. For the majority of magnets, insignificant forces were attained beyond 2 mm of separation. Magnets with large pole face areas and longer magnetic axes provided the greatest force. A select range of magnet configurations exhibited suitable and reliable attractive forces and therefore could be advocated for prescribed clinical application.
Cann, Arnie; And Others
1981-01-01
Undergraduates evaluated the qualifications of an attractive, average, or unattractive male or female applicant. Ratings of specific qualifications preceded or followed an overall and hiring decision rating. The order variable influenced ratings of specific qualifications but not the overall or hiring decision. Male and attractive applicants were…
Three-Body Antikaon-Nucleon Systems
Czech Academy of Sciences Publication Activity Database
Shevchenko, Nina V.
2017-01-01
Roč. 58, č. 1 (2017), č. článku UNSP 6. ISSN 0177-7963 R&D Projects: GA ČR(CZ) GA15-04301S Institutional support: RVO:61389005 Keywords : three-body * antikaon-nucleon * K p interactions Subject RIV: BE - Theoretical Physics OBOR OECD: Atom ic, molecular and chemical physics (physics of atom s and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 0.877, year: 2016
The role of atomic level steric effects and attractive forces in protein folding.
Lammert, Heiko; Wolynes, Peter G; Onuchic, José N
2012-02-01
Protein folding into tertiary structures is controlled by an interplay of attractive contact interactions and steric effects. We investigate the balance between these contributions using structure-based models using an all-atom representation of the structure combined with a coarse-grained contact potential. Tertiary contact interactions between atoms are collected into a single broad attractive well between the C(β) atoms between each residue pair in a native contact. Through the width of these contact potentials we control their tolerance for deviations from the ideal structure and the spatial range of attractive interactions. In the compact native state dominant packing constraints limit the effects of a coarse-grained contact potential. During folding, however, the broad attractive potentials allow an early collapse that starts before the native local structure is completely adopted. As a consequence the folding transition is broadened and the free energy barrier is decreased. Eventually two-state folding behavior is lost completely for systems with very broad attractive potentials. The stabilization of native-like residue interactions in non-perfect geometries early in the folding process frequently leads to structural traps. Global mirror images are a notable example. These traps are penalized by the details of the repulsive interactions only after further collapse. Successful folding to the native state requires simultaneous guidance from both attractive and repulsive interactions. Copyright © 2011 Wiley Periodicals, Inc.
Three-body Supersymmetric Top Decays
Belyaev, A; Lola, S; Belyaev, Alexander; Ellis, John; Lola, Smaragda
2000-01-01
We discuss three-body supersymmetric top decays, in schemes both with andwithout R-parity conservation, assuming that sfermion masses are larger thanm_t. We find that MSSM top decays into chargino/neutralino pairs have a strongkinematic suppression in the region of the supersymmetric parameter spaceconsistent with the LEP limits, with a decay width =< 10^{-5} GeV. MSSM topdecays into neutralino pairs have less kinematical suppression, but require aflavour-changing vertex, and are likely to have a smaller rate. On the otherhand, R-violating decays to single charginos, neutralinos and conventionalfermions can be larger for values of the R-violating couplings still permittedby other upper limits. The cascade decays of the charginos and neutralinos maylead to spectacular signals with explicit lepton-number violation, such aslike-sign lepton events.
Fuentes-Herrera, M; Moreno-Razo, J A; Guzmán, O; López-Lemus, J; Ibarra-Tandi, B
2016-06-07
Molecular simulations in the canonical and isothermal-isobaric ensembles were performed to study the effect of varying the shape of the intermolecular potential on the phase diagram, critical, and interfacial properties of model fluids. The molecular interactions were modeled by the Approximate Non-Conformal (ANC) theory potentials. Unlike the Lennard-Jones or Morse potentials, the ANC interactions incorporate parameters (called softnesses) that modulate the steepness of the potential in their repulsive and attractive parts independently. This feature allowed us to separate unambiguously the role of each region of the potential on setting the thermophysical properties. In particular, we found positive linear correlation between all critical coordinates and the attractive and repulsive softness, except for the critical density and the attractive softness which are negatively correlated. Moreover, we found that the physical properties related to phase coexistence (such as span of the liquid phase between the critical and triple points, variations in the P-T vaporization curve, interface width, and surface tension) are more sensitive to changes in the attractive softness than to the repulsive one. Understanding the different roles of attractive and repulsive forces on phase coexistence may contribute to developing more accurate models of liquids and their mixtures.
Three-body forces mandated by Poincare invariance
International Nuclear Information System (INIS)
Coester, F.
1986-01-01
Poincare invariant models for the three-nucleon system are examined which have the same heuristic relation to field theories as the nonrelativistic nuclear models. The generators of the infinitesimal dynamical transformations can be obtained as functions of the kinematic generators, the invariant mass operator of the interacting system, and additional operators. These additional operators are the components of the Newton-Wigner position operator in the instant form, and the transverse components of the spin in the front form. The relativistic dynamics of Poincare transformations is examined, and then these concepts are applied to two-nucleon systems. The transition to a fully interacting three-nucleon system is made
薮野, 浩司; 大和田, 竜太郎; 青島, 伸治; Hiroshi, YABUNO; Ryotaro, OOWADA; Nobuharu, AOSHIMA; 筑波大学; 筑波大学院; 筑波大学
1998-01-01
This paper presents the limitation of the magnetic circuit method. The force between magnetic bodies can be approximated accurately by the magnetic circuit method. Therefore this method has been used widely for the estimation of magnetic force. However this method is limited by the magnetic leakage and can be not used in the case when the gap between the magnetic bodies is wide. It is very important to clarify the limitation of the magnetic circuit method. In this research, the force of an el...
Studies of the nuclear three-body system with three dimensional Faddeev calculations
Liu, Hang
A three-body system consists of either a bound state of three particles with definite binding energy or a beam of single particles scattered from a target, where two of the particles are bound. Of the particles are nucleons, the interactions between them are strong and short ranged. A theoretical framework for studying the dynamics of a nuclear three-body system is the Faddeev scheme. In this work the equation for three-body scattering and the bound state are formulated in momentum space, and directly solved in terms of vector variables. For three identical bosons the Faddeev equation for scattering is a three- dimensional inhomogeneous integral equation in five variables, and is solved by Padé summation. The equation for the bound state is a homogeneous one in three variables, and is solved by a Lanczos' type method. The corresponding algorithms are presented, and their numerical feasibility is demonstrated. Elastic as well as inelastic scattering processes in the intermediate energy regime up to 1 GeV incident energy are studied for the first within a Faddeev scheme. The two-body force employed is of Malfliet-Tjon type. Specific emphasis is placed on studying the convergence of the multiple scattering series given by the Faddeev equations. For the bound state, a three-body force of Fujita- Miyazawa type is incorporated in addition to the two-body force. The effects of this three-body force on the bound state properties are investigated.
Algebraic diagrammatic construction formalism with three-body interactions
Raimondi, Francesco; Barbieri, Carlo
2018-05-01
Background: Self-consistent Green's function theory has recently been extended to the basic formalism needed to account for three-body interactions [Carbone, Cipollone, Barbieri, Rios, and Polls, Phys. Rev. C 88, 054326 (2013), 10.1103/PhysRevC.88.054326]. The contribution of three-nucleon forces has so far been included in ab initio calculations on nuclear matter and finite nuclei only as averaged two-nucleon forces. Purpose: We derive the working equations for all possible two- and three-nucleon terms that enter the expansion of the self-energy up to the third order, thus including the interaction-irreducible (i.e., not averaged) diagrams with three-nucleon forces that have been previously neglected. Methods: We employ the algebraic diagrammatic construction up to the third order as an organization scheme for generating a nonperturbative self-energy, in which ring (particle-hole) and ladder (particle-particle) diagrams are resummed to all orders. Results: We derive expressions of the static and dynamic self-energy up to the third order, by taking into account the set of diagrams required when either the skeleton or nonskeleton expansions of the single-particle propagator are assumed. A hierarchy of importance among different diagrams is revealed, and a particular emphasis is given to a third-order diagram [see Fig. 2(c)] that is expected to play a significant role among those featuring an interaction-irreducible three-nucleon force. Conclusion: A consistent formalism to resum at infinite order correlations induced by three-nucleon forces in the self-consistent Green's function theory is now available and ready to be implemented in the many-body solvers.
Shukla, P. K.; Eliasson, B.; Akbari-Moghanjoughi, M.
2013-03-01
In a recent paper, Bonitz, Pehlke, and Schoof [Phys. Rev. E10.1103/PhysRevE.87.033105 87, 033105 (2013)], hereafter referred to as BPS, have raised some points against the Shukla-Eliasson attractive potential [P. K. Shukla and B. Eliasson, Phys. Rev. Lett.0031-900710.1103/PhysRevLett.108.165007 108, 165007 (2012); P. K. Shukla and B. Eliasson, Phys. Rev. Lett.0031-900710.1103/PhysRevLett.108.219902 108, 219902(E) (2012); P. K. Shukla and B. Eliasson, Phys. Rev. Lett.10.1103/PhysRevLett.109.019901 109, 019901(E) (2012)], hereafter referred to as SEAP, around a stationary test charge in a quantum plasma. Our objective here is to discuss the insufficiency of the BPS reasoning concerning the applicability of the linearized quantum hydrodynamic theory, as well as to point out the shortcomings in BPS’s arguments and to suggest how to salvage BPS’s density functional theory and simulations, which have failed to produce results that correctly match with that of Shukla and Eliasson.
Long-range attractive forces extending from the alumina’s nanolayer surface in aqueous solutions
Directory of Open Access Journals (Sweden)
Leonid A. Kaledin
2015-07-01
Full Text Available Aluminum oxide-hydroxide nanolayer with a thickness of approximately 1.2 nm is electroadhesively deposited onto silicious support material with large surface area of about 50 m2/g, forming a highly electropositive composite of boehmite nanolayer in the form of monocrystalline oxide/hydroxide (α-Al2O3·H2O on the second electronegative solid. The composite can be viewed as a sphere with a rough surface and charge density of approximately 0.08 C/m2. This creates a significant electric field with negligible screening (ka ≪ 1 in the region close to the surface of the nanocomposite. This field attracts nano- and micron-sized particles from as far as 200 μm in a few seconds, many orders of magnitude greater than conventional Derjaguin–Landau–Verwey–Overbeek (DLVO theory, which predicts only nanometer-scale effects arising from the presence of the surface. The strong electric field on the surface is then able to retain small particles such as viruses, atomically thin sheets of graphene oxide, RNA, DNA, proteins, dyes as well as heavy metals such as cobalt, arsenic, and lead. Alumina’s nanolayer surface can be further functionalized by adding other sub-micron or nano-sized particles to target a specific contaminant. An example is shown where alumina nanolayer is coated with nano-sized iron monohydrate to yield an arsenic sorbent that shows high sorption capacity.
International Nuclear Information System (INIS)
Danilova, N P
2015-01-01
From the Editorial Board. In a brief followup to the talk by E I Kats on 'Van der Waals, Casimir, and Lifshitz forces in soft matter' (see pp. 892 – 896 of this issue) at the E M Lifshitz centennial session of the Physical Sciences Division of the Russian Academy of Sciences, an interesting and instructive story was told by Nina Petrovna Danilova (Department of Low Temperature Physics and Superconductivity, Faculty of Physics, Moscow State University) of how E M Lifshitz was enlisted to explain I I Abrikosova's and B V Derjaguin's experimental results. The Editorial Board of Uspekhi Fizicheskikh Nauk (UFN) [Physics-Uspekhi] journal found the story appropriate to be published in the 'Letters to the Editor' section of UFN in a jubilee selection of works marking the centennial of E M Lifshitz' birth. (letters to the editors)
Itoh, Satoru G; Okumura, Hisashi
2013-03-30
We propose a new type of the Hamiltonian replica-exchange method (REM) for molecular dynamics (MD) and Monte Carlo simulations, which we refer to as the Coulomb REM (CREM). In this method, electrostatic charge parameters in the Coulomb interactions are exchanged among replicas while temperatures are exchanged in the usual REM. By varying the atom charges, the CREM overcomes free-energy barriers and realizes more efficient sampling in the conformational space than the REM. Furthermore, this method requires only a smaller number of replicas because only the atom charges of solute molecules are used as exchanged parameters. We performed Coulomb replica-exchange MD simulations of an alanine dipeptide in explicit water solvent and compared the results with those of the conventional canonical, replica exchange, and van der Waals REMs. Two force fields of AMBER parm99 and AMBER parm99SB were used. As a result, the CREM sampled all local-minimum free-energy states more frequently than the other methods for both force fields. Moreover, the Coulomb, van der Waals, and usual REMs were applied to a fragment of an amyloid-β peptide (Aβ) in explicit water solvent to compare the sampling efficiency of these methods for a larger system. The CREM sampled structures of the Aβ fragment more efficiently than the other methods. We obtained β-helix, α-helix, 3(10)-helix, β-hairpin, and β-sheet structures as stable structures and deduced pathways of conformational transitions among these structures from a free-energy landscape. Copyright © 2012 Wiley Periodicals, Inc.
Azadi, Mehdi; Nguyen, Anh V; Yakubov, Gleb E
2015-02-17
Interfacial gas enrichment of dissolved gases (IGE) has been shown to cover hydrophobic solid surfaces in water. The atomic force microscopy (AFM) data has recently been supported by molecular dynamics simulation. It was demonstrated that IGE is responsible for the unexpected stability and large contact angle of gaseous nanobubbles at the hydrophobic solid-water interface. Here we provide further evidence of the significant effect of IGE on an attractive force between hydrophobic solid surfaces in water. The force in the presence of dissolved gas, i.e., in aerated and nonaerated NaCl solutions (up to 4 M), was measured by the AFM colloidal probe technique. The effect of nanobubble bridging on the attractive force was minimized or eliminated by measuring forces on the first approach of the AFM probe toward the flat hydrophobic surface and by using high salt concentrations to reduce gas solubility. Our results confirm the presence of three types of forces, two of which are long-range attractive forces of capillary bridging origin as caused by either surface nanobubbles or gap-induced cavitation. The third type is a short-range attractive force observed in the absence of interfacial nanobubbles that is attributed to the IGE in the form of a dense gas layer (DGL) at hydrophobic surfaces. Such a force was found to increase with increasing gas saturation and to decrease with decreasing gas solubility.
Universality in low energy three-body systems
International Nuclear Information System (INIS)
Amorim, A.E.A.; Tomio, L; Frederico, T.
1997-01-01
The renormalizability of the quantum theory of non-relativistic three-body system with zero range interaction, warranties that all the low-energy three-body properties are well defined and the low-energy two-body and only one three-body physical information are known. Considering this observation, we have shown that the conditions for the occurrence of Efimov states can be easily reached with any model of short range potential where the three-body ground state and the corresponding binding energy of the subsystems are kept fixed. This approach was applied to the recently discovered halo nuclei. (author)
The three body problem with energy dependent potentials
International Nuclear Information System (INIS)
Kim, Y.E.; McKay, C.M.; McKellar, B.H.J.
1975-10-01
It is shown how to generalize the three body equations of Faddeev, and of Karlsson and Zeiger, to include the case when the two body potential is energy dependent. Such generalizations will prove useful in the three nucleon problem and in three body models of nuclear reactions. (author)
A simple coordinate space approach to three-body problems ...
Indian Academy of Sciences (India)
We show how to treat the dynamics of an asymmetric three-body system consisting of one heavy and two identical light particles in a simple coordinate space variational approach. The method is constructive and gives an efﬁcient way of resolving a three-body system to an effective two-body system. It is illustrated by ...
Assessment of mechanical and three-body abrasive wear peculiarity ...
Indian Academy of Sciences (India)
The three-body abrasive wear characteristic of fabricated composites has been assessed under different operating conditions. For this, the three-body abrasion test is done on dry abrasion test rig (TR-50)and analysed using Taguchi's experimental design scheme and analysis of variance. The results obtained from these ...
Three-body interactions and the Landau levels using Nikiforov ...
Indian Academy of Sciences (India)
In this article, the eigenvalues for the three-body interactions on the line and the Landau levels in the presence of topological defects have been regenerated by the Nikiforov–Uvarov (NU) method. Two exhaustive lists of such exactly solvable potentials are given. Keywords. Nikiforov–Uvarov (NU) method; three-body ...
Approximate Coulomb effects in the three-body scattering problem
International Nuclear Information System (INIS)
Haftel, M.I.; Zankel, H.
1981-01-01
From the momentum space Faddeev equations we derive approximate expressions which describe the Coulomb-nuclear interference in the three-body elastic scattering, rearrangement, and breakup problems and apply the formalism to p-d elastic scattering. The approximations treat the Coulomb interference as mainly a two-body effect, but we allow for the charge distribution of the deuteron in the p-d calculations. Real and imaginary parts of the Coulomb correction to the elastic scattering phase shifts are described in terms of on-shell quantities only. In the case of pure Coulomb breakup we recover the distorted-wave Born approximation result. Comparing the derived approximation with the full Faddeev p-d elastic scattering calculation, which includes the Coulomb force, we obtain good qualitative agreement in S and P waves, but disagreement in repulsive higher partial waves. The on-shell approximation investigated is found to be superior to other current approximations. The calculated differential cross sections at 10 MeV raise the question of whether there is a significant Coulomb-nuclear interference at backward angles
Three-body segment musculoskeletal model of the upper limb
Directory of Open Access Journals (Sweden)
Valdmanová L.
2013-06-01
Full Text Available The main aim is to create a computational three-body segment model of an upper limb of a human body for determination of muscle forces generated to keep a given loaded upper limb position. The model consists of three segments representing arm, forearm, hand and of all major muscles connected to the segments. Muscle origins and insertions determination corresponds to a real anatomy. Muscle behaviour is defined according to the Hill-type muscle model consisting of contractile and viscoelastic element. The upper limb is presented by a system of three rigid bars connected by rotational joints. The whole limb is fixed to the frame in the shoulder joint. A static balance problem is solved by principle of virtual work. The system of equation describing the musculoskeletal system is overdetermined because more muscles than necessary contribute to get the concrete upper limb position. Hence the mathematical problem is solved by an optimization method searching the least energetically-consuming solution. The upper limb computational model is verified by electromyography of the biceps brachii muscle.
Diffusion Monte Carlo calculation of three-body systems
International Nuclear Information System (INIS)
Lu Mengjiao; Lin Qihu; Ren Zhongzhou
2012-01-01
The application of the diffusion Monte Carlo algorithm in three-body systems is studied. We develop a program and use it to calculate the property of various three-body systems. Regular Coulomb systems such as atoms, molecules, and ions are investigated. The calculation is then extended to exotic systems where electrons are replaced by muons. Some nuclei with neutron halos are also calculated as three-body systems consisting of a core and two external nucleons. Our results agree well with experiments and others' work. (authors)
Scattering Length Scaling Laws for Ultracold Three-Body Collisions
International Nuclear Information System (INIS)
D'Incao, J.P.; Esry, B.D.
2005-01-01
We present a simple and unifying picture that provides the energy and scattering length dependence for all inelastic three-body collision rates in the ultracold regime for three-body systems with short-range two-body interactions. Here, we present the scaling laws for vibrational relaxation, three-body recombination, and collision-induced dissociation for systems that support s-wave two-body collisions. These systems include three identical bosons, two identical bosons, and two identical fermions. Our approach reproduces all previous results, predicts several others, and gives the general form of the scaling laws in all cases
Chervanyov, A I
2016-12-28
By making use of the polymer reference interaction site model, we analytically study the effect of attractive interactions between polymers on the effective forces acting between colloids immersed in a polymer system. The performed theoretical analysis has no restrictions with respect to the polymer density and relative sizes of the colloids and polymers. The polymer mediated (PM) potential acting between colloids is shown to significantly depend on the strength and range of the polymer-polymer interactions. In the nano-particle limit, where the colloid radius is much smaller than the polymer gyration radius, the presence of attractive polymer-polymer interactions causes only quantitative changes to the PM potential. In the opposite limit of relatively large colloids, the polymer-polymer interactions revert the sign of the total effective force acting between colloids so that this force becomes attractive at sufficiently large polymer densities. With the objective to study an intricate interplay between the attractive PM forces and steric repulsion in different polymer density regimes, we calculate the second virial coefficient B of the total effective potential acting between colloids. The dependence of B on the polymer density is discussed in detail, revealing several novel features of the PM interactions caused by the presence of attractive polymer-polymer interactions.
Assessment of mechanical and three-body abrasive wear peculiarity ...
Indian Academy of Sciences (India)
directional fabric reinforcement offers a unique solution for ... showed good performance to the three-body abrasive wear. .... plied by the Pioneer Chemical Company, Delhi, India. ..... Theoretical and measured densities of composites, along.
Three-body molecular description of 9Be
International Nuclear Information System (INIS)
Revai, J.; Matveenko, A.V.
1979-01-01
The low lying spectrum of the 9 Be nucleus is calculated in the α+α+n three-body model. The molecular approach to this three-body problem based on the exact evalution of the two-center wave functions for separable n-α potentials is considered in detail. The numerical results are obtained in the generalized Born-Oppenheimer approximation which preserves total angular momentum and parity
Three-body vertices with two-body techniques
International Nuclear Information System (INIS)
Mitra, A.N.; Sharma, V.K.
1976-01-01
It has long been recognized that vertex functions for few particle systems provide a convenient medium for the analysis of reactions in the language of Feynman diagrams, analogously to elementary particle processes. The development of three-particle theory during the last decade has provided considerably more impetus for the use of the language of three-body vertex functions through the possibility of their 'exact' evaluations with only two-body input. While three-body vertices are probably superfluous for the description of only three-body processes (for which exact amplitudes are already available) their practical usefulness often extends to reactions involving more than three-particle systems (for which 'exact' amplitudes are still a distant goal), as long as such systems can be meaningfully described in terms of not more than three particles playing the active role. This paper investigates a simplified construction of three-body vertices. This must check against their standard definition as overlap integral. Unfortunately this definition involves a non-trivial normalization of three-body wave functions with realistic NN potentials, and has little practical scope for extension beyond A=3. (Auth.)
Shukla, P. K.; Eliasson, B.; Akbari-Moghanjoughi, M.
2013-01-01
In a paper on arXiv, Bonitz et al (2012 arXiv:1205.4922v1 [physics.plasm-ph]) (hereafter referred to as BPS) erroneously attributed the qualitative discrepancy between their density functional theory (DFT) simulation results with the analytical discovery of the Shukla-Eliasson (SE) attractive force which brings ions closer to the failure of the linearized quantum hydrodynamic theory. In this paper, we describe the underlying physics of the novel SE attractive force and its validity, as well as discuss some of the key features of the well-established quantum hydrodynamic theory and working mechanisms for DFT simulations, in addition to giving some critical notes on the falsified and misleading conclusions presented by BPS in their dubious paper. Furthermore, we also present a mass-density value for possible 4He metallic plasma lattice formation under the SE force.
International Nuclear Information System (INIS)
Shukla, P K; Eliasson, B; Akbari-Moghanjoughi, M
2013-01-01
In a paper on arXiv, Bonitz et al (2012 arXiv:1205.4922v1 [physics.plasm-ph]) (hereafter referred to as BPS) erroneously attributed the qualitative discrepancy between their density functional theory (DFT) simulation results with the analytical discovery of the Shukla-Eliasson (SE) attractive force which brings ions closer to the failure of the linearized quantum hydrodynamic theory. In this paper, we describe the underlying physics of the novel SE attractive force and its validity, as well as discuss some of the key features of the well-established quantum hydrodynamic theory and working mechanisms for DFT simulations, in addition to giving some critical notes on the falsified and misleading conclusions presented by BPS in their dubious paper. Furthermore, we also present a mass-density value for possible 4 He metallic plasma lattice formation under the SE force.
Spectral sum rules for the three-body problem
International Nuclear Information System (INIS)
Bolle, D.; Osborn, T.A.
1982-01-01
This paper derives a number of sum rules for nonrelativistic three-body scattering. These rules are valid for any finite region μ in the six-dimensional coordinate space. They relate energy moments of the trace of the onshell time-delay operator to the energy-weighted probability for finding the three-body bound-state wave functions in the region μ. If μ is all of the six-dimensional space, the global form of the sum rules is obtained. In this form the rules constitute higher-order Levinson's theorems for the three-body problem. Finally, the sum rules are extended to allow the energy momtns have complex powers
Analytical treatment of Coriolis coupling for three-body systems
Energy Technology Data Exchange (ETDEWEB)
Poirier, Bill
2005-01-31
In a previous article [J. Chem. Phys. 108 (1998) 5216], an efficient method was presented for performing 'exact' quantum calculations for the three-body rovibrational Hamiltonian, within the helicity-conserving approximation. This approach makes use of a certain three-body ''effective potential,'' enabling the same bend angle basis set to be employed for all values of the rotational quantum numbers, J, K and M. In the present work, the method is extended to incorporate Coriolis coupling, for which the relevant matrix elements are derived exactly. These can be used to solve the full three-body rovibrational problem, in the standard Jacobi coordinate vector embedding. Generalization of the method for coupled kinetic energy operators arising from other coordinate systems, embeddings, and/or system sizes, is also discussed.
Gravitational waves from periodic three-body systems.
Dmitrašinović, V; Suvakov, Milovan; Hudomal, Ana
2014-09-05
Three bodies moving in a periodic orbit under the influence of Newtonian gravity ought to emit gravitational waves. We have calculated the gravitational radiation quadrupolar waveforms and the corresponding luminosities for the 13+11 recently discovered three-body periodic orbits in Newtonian gravity. These waves clearly allow one to distinguish between their sources: all 13+11 orbits have different waveforms and their luminosities (evaluated at the same orbit energy and body mass) vary by up to 13 orders of magnitude in the mean, and up to 20 orders of magnitude for the peak values.
Efimov resonances in atomic three-body systems
International Nuclear Information System (INIS)
Mezei, J. Zs.; Papp, Z.
2006-01-01
In a recent work [Phys. Rev. Lett. 94, 143201 (2005)], we reported an accumulation of three-body resonant states attached to n=2 and higher two-body thresholds. A more careful investigation revealed that there are resonances of the same kind above the n=1 threshold as well. This suggests that the resonances attached to the thresholds are Efimov resonances
The three-body problem from Pythagoras to Hawking
Valtonen, Mauri; Kholshevnikov, Konstantin; Mylläri, Aleksandr; Orlov, Victor; Tanikawa, Kiyotaka
2016-01-01
This book, written for a general readership, reviews and explains the three-body problem in historical context reaching to latest developments in computational physics and gravitation theory. The three-body problem is one of the oldest problems in science and it is most relevant even in today’s physics and astronomy. The long history of the problem from Pythagoras to Hawking parallels the evolution of ideas about our physical universe, with a particular emphasis on understanding gravity and how it operates between astronomical bodies. The oldest astronomical three-body problem is the question how and when the moon and the sun line up with the earth to produce eclipses. Once the universal gravitation was discovered by Newton, it became immediately a problem to understand why these three-bodies form a stable system, in spite of the pull exerted from one to the other. In fact, it was a big question whether this system is stable at all in the long run. Leading mathematicians attacked this problem over more than...
The three-body problem and equivariant Riemannian geometry
Alvarez-Ramírez, M.; García, A.; Meléndez, J.; Reyes-Victoria, J. G.
2017-08-01
We study the planar three-body problem with 1/r2 potential using the Jacobi-Maupertuis metric, making appropriate reductions by Riemannian submersions. We give a different proof of the Gaussian curvature's sign and the completeness of the space reported by Montgomery [Ergodic Theory Dyn. Syst. 25, 921-947 (2005)]. Moreover, we characterize the geodesics contained in great circles.
Modified Strum functions method in the nuclear three body problem
International Nuclear Information System (INIS)
Nasyrov, M.; Abdurakhmanov, A.; Yunusova, M.
1997-01-01
Fadeev-Hahn equations in the nuclear three-body problem were solved by modified Sturm functions method. Numerical calculations were carried out the square well potential. It was shown that the convergence of the method is high and the binding energy value is in agreement with experimental one (A.A.D.)
Poincaré and the three body problem
Barrow-Green, June
1997-01-01
The idea of chaos figures prominently in mathematics today. It arose in the work of one of the greatest mathematicians of the late 19th century, Henri Poincaré, on a problem in celestial mechanics: the three body problem. This ancient problem-to describe the paths of three bodies in mutual gravitational interaction-is one of those which is simple to pose but impossible to solve precisely. Poincaré's famous memoir on the three body problem arose from his entry in the competition celebrating the 60th birthday of King Oscar of Sweden and Norway. His essay won the prize and was set up in print as a paper in Acta Mathematica when it was found to contain a deep and critical error. In correcting this error Poincaré discovered mathematical chaos, as is now clear from Barrow-Green's pioneering study of a copy of the original memoir annotated by Poincaré himself, recently discovered in the Institut Mittag-Leffler in Stockholm. Poincaré and the Three Body Problem opens with a discussion of the development of the th...
Three-body interactions and the Landau levels using Nikiforov
Indian Academy of Sciences (India)
In this article, the eigenvalues for the three-body interactions on the line and the Landau levels in the presence of topological defects have been regenerated by the Nikiforov–Uvarov (NU) method. Two exhaustive lists of such exactly solvable potentials are given.
Optimization of the variational basis in the three body problem
International Nuclear Information System (INIS)
Simenog, I.V.; Pushkash, O.M.; Bestuzheva, A.B.
1995-01-01
The procedure of variational oscillator basis optimization is proposed to the calculation the energy spectra of three body systems. The hierarchy of basis functions is derived and energies of ground and excited states for three gravitating particles is obtained with high accuracy. 12 refs
Bonitz, M.; Pehlke, E.; Schoof, T.
2013-11-01
In a recent paper (Shukla et al 2013 Phys. Scr. 87 018202) the authors criticized our analysis of the screened proton potential in dense hydrogen that was based on ab initio density functional theory (DFT) simulations (Bonitz et al 2013 Phys. Rev. E 87 037102). In particular, they attributed the absence of the Shukla-Eliasson attractive force between protons in the DFT simulations to a failure of DFT. Here we discuss in detail their arguments and show that their conclusions are incorrect.
International Nuclear Information System (INIS)
Papp, Z.; Plessas, W.
1996-01-01
We demonstrate the feasibility and efficiency of the Coulomb-Sturmian separable expansion method for generating accurate solutions of the Faddeev equations. Results obtained with this method are reported for several benchmark cases of bosonic and fermionic three-body systems. Correct bound-state results in agreement with the ones established in the literature are achieved for short-range interactions. We outline the formalism for the treatment of three-body Coulomb systems and present a bound-state calculation for a three-boson system interacting via Coulomb plus short-range forces. The corresponding result is in good agreement with the answer from a recent stochastic-variational-method calculation. copyright 1996 The American Physical Society
Exact calculation of three-body contact interaction to second order
International Nuclear Information System (INIS)
Kaiser, N.
2012-01-01
For a system of fermions with a three-body contact interaction the second-order contributions to the energy per particle anti E(k f ) are calculated exactly. The three-particle scattering amplitude in the medium is derived in closed analytical form from the corresponding two-loop rescattering diagram. We compare the (genuine) second-order three-body contribution to anti E(k f )∝k f 10 with the second-order term due to the density-dependent effective two-body interaction, and find that the latter term dominates. The results of the present study are of interest for nuclear many-body calculations where chiral three-nucleon forces are treated beyond leading order via a density-dependent effective two-body interaction. (orig.)
Three-body unitarity in the finite volume
Energy Technology Data Exchange (ETDEWEB)
Mai, M. [The George Washington University, Washington, DC (United States); Doering, M. [The George Washington University, Washington, DC (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
2017-12-15
The physical interpretation of lattice QCD simulations, performed in a small volume, requires an extrapolation to the infinite volume. A method is proposed to perform such an extrapolation for three interacting particles at energies above threshold. For this, a recently formulated relativistic 3 → 3 amplitude based on the isobar formulation is adapted to the finite volume. The guiding principle is two- and three-body unitarity that imposes the imaginary parts of the amplitude in the infinite volume. In turn, these imaginary parts dictate the leading power-law finite-volume effects. It is demonstrated that finite-volume poles arising from the singular interaction, from the external two-body sub-amplitudes, and from the disconnected topology cancel exactly leaving only the genuine three-body eigenvalues. The corresponding quantization condition is derived for the case of three identical scalar-isoscalar particles and its numerical implementation is demonstrated. (orig.)
The scattering matrix element of the three body reactive collision
International Nuclear Information System (INIS)
Morsy, M.W.; Hilal, A.A.; El-Sabagh, M.A.
1980-08-01
The optical model approximation has been applied to a previously derived set of coupled equations representing the dynamics of the three-body reactive scattering. The Schroedinger equation obtained describing the scattering problem has then been solved by inserting the effective mass approximation. The asymptotic requirements for both the entrance and exit channels, respectively, have been supplied to give the scattering matrix element of the reactive collision. (author)
Nuclear three-body problem and energy-dependent potentials
International Nuclear Information System (INIS)
Abdurakhmanov, A.; Akhmadkhodzhaev, B.; Zubarev, A.L.; Irgaziev, B.F.
1985-01-01
Energy-dependent potentials in the three-body problem are being considered. Three-particle equations for the case of pairing energy-dependent potentials are generalized and the problems related to this ambiguous generalization are investigated. In terms of the equations obtained the tritium binding energy and vertex coupling constants (Tdn) and (Tdν) are evaluated. The binding energy and, especially, coupling constants are shown to be sensitive to a shape of the energy-dependent potential
Three-body decays: structure, decay mechanism and fragment properties
International Nuclear Information System (INIS)
Alvarez-Rodriguez, R.; Jensen, A.S.; Fedorov, D.V.; Fynbo, H.O.U.; Kirsebom, O.S.; Garrido, E.
2009-01-01
We discuss the three-body decay mechanisms of many-body resonances. R-matrix sequential description is compared with full Faddeev computation. The role of the angular momentum and boson symmetries is also studied. As an illustration we show the computed ?-particle energy distribution after the decay of 12 C(1 + ) resonance at 12.7 MeV. This article is based on the presentation by R. Alvarez-Rodriguez at the Fifth Workshop on Critical Stability, Erice, Sicily. (author)
Structures of two-dimensional three-body systems
International Nuclear Information System (INIS)
Ruan, W.Y.; Liu, Y.Y.; Bao, C.G.
1996-01-01
Features of the structure of L = 0 states of a two-dimensional three-body model system have been investigated. Three types of permutation symmetry of the spatial part, namely symmetric, antisymmetric, and mixed, have been considered. A comparison has been made between the two-dimensional system and the corresponding three-dimensional one. The effect of symmetry on microscopic structures is emphasized. (author)
Continuum capture in the three-body problem
International Nuclear Information System (INIS)
Sellin, I.A.
1980-01-01
The three-body problem, especially the problem of electron capture to the continuum in heavy particle collisions is reviewed. Major topics covered include: second born-induced asymmetry in electron capture to the continuum; historical context, links to other tests of atomic scattering theory; experiments characterizing the velocity distribution of ECC electrons; other atomic physics tests of high velocity Born expansions; atom capture; capture by positrons; and pion capture to the continuum
Very massive runaway stars from three-body encounters
Gvaramadze, Vasilii V.; Gualandris, Alessia
2011-01-01
Very massive stars preferentially reside in the cores of their parent clusters and form binary or multiple systems. We study the role of tight very massive binaries in the origin of the field population of very massive stars. We performed numerical simulations of dynamical encounters between single (massive) stars and a very massive binary with parameters similar to those of the most massive known Galactic binaries, WR 20a and NGC 3603-A1. We found that these three-body encounters could be responsible for the origin of high peculiar velocities (≥70 km s-1) observed for some very massive (≥60-70 M⊙) runaway stars in the Milky Way and the Large Magellanic Cloud (e.g. λ Cep, BD+43°3654, Sk -67°22, BI 237, 30 Dor 016), which can hardly be explained within the framework of the binary-supernova scenario. The production of high-velocity massive stars via three-body encounters is accompanied by the recoil of the binary in the opposite direction to the ejected star. We show that the relative position of the very massive binary R145 and the runaway early B-type star Sk-69°206 on the sky is consistent with the possibility that both objects were ejected from the central cluster, R136, of the star-forming region 30 Doradus via the same dynamical event - a three-body encounter.
Local Momenta and a Three-Body Gauge
Schillaci, Michael Jay
2000-06-01
Here I discuss position-dependent, phlocal momentum which depend upon the logarithmic gradient of a continuum Coulomb pair. These momenta have become increasingly important in the modeling of three-body scattering phenomena, while their precise mathematical and physical nature has remained unexplored. These momenta are analytic at all values of the radial separation, except possibly at zero, and can be used to illustrate why the reigning 3C wavefunction works so well in describing many phlight-atom ion processes. I calculate the contributions for several subsystems, and explain the schillaci/threebody/ momentum.html>asymmetric results achieved by Wiese(L.M. Wiese phet al.), PRL 25, 4982 (1997)., on the breakup of the (H_3^+) ion - a massive three-body system. I propose that the local momentum herein formulated become part of a three-body gauge constraint. When applied, a non-vanishing, position-dependent phase will modulate the resulting transition amplitude. The size of this modulation depends critically upon the system.
International Nuclear Information System (INIS)
Wamba, Etienne; Mohamadou, Alidou; Ekogo, Thierry B.; Atangana, Jacque; Kofane, Timoleon C.
2011-01-01
The parametric modulational instability for a discrete nonlinear Schrödinger equation with a cubic–quintic nonlinearity is analyzed. This model describes the dynamics of BECs, with both two- and three-body interatomic interactions trapped in an optical lattice. We identify and discuss the salient features of the three-body interaction in the parametric modulational instability. It is shown that the three-body interaction term can both, shift as well as narrow the window of parametric instability, and also change the behavior of a modulationally stable and parametrically unstable BEC with attractive two-body interaction. We explore this instability through the multiple-scale analysis and identify it numerically. The effect of the three body losses have also been investigated. -- Highlights: ► The parametric MI for the 1D GPE with a cubic–quintic nonlinearity is analyzed. ► The two- and three-body recombination and time-dependent scattering length is considered. ► We generate bright matter waves soliton through MI.
Photofragment translational spectroscopy of three body dissociations and free radicals
Energy Technology Data Exchange (ETDEWEB)
North, Simon William [Univ. of California, Berkeley, CA (United States)
1995-04-01
This dissertation describes several three-body dissociations and the photodissociation of methyl radicals studied using photofragment translational spectroscopy. The first chapter provides an introduction to three body dissociation, examines current experimental methodology, and includes a discussion on the treatment of photofragment translational spectroscopy data arising from three-body fragmentation. The ultraviolet photodissociation of azomethane into two methyl radicals and nitrogen is discussed in chapter 2. Chapter 3 describes the photodissociation of acetone at 248 nm and 193 nm. At 248 nm the translational energy release from the initial C-C bond cleavage matches the exit barrier height and a comparison with results at 266 nm suggests that
Scalar three body decays and signals for new physics
International Nuclear Information System (INIS)
Adhikari, R.; Mukhopadhyaya, B.
1994-07-01
If massive invisible particles are pair-produced in a three-body decay, then the energy distribution of the other (visible) product is sensitive to the mass of the invisible pair. We use this fact in the context of a Higgs boson decaying into (i) a Z-boson and two massive neutrinos of a fourth generation, and (ii) a Z and two lightest supersymmetric particles in the minimal supersymmetric standard model. We discuss how the Z-energy spectrum in each case can reflect the values of the parameters of such models. (author). 18 refs, 3 figs
LHCb: Can LHCb Study Three Body Decays with Neutrals?
Fawcett, W
2013-01-01
In this poster we present the first attempt to use a new method to measure CP violation in Dalitz plots. This method is unbinned, model independent and has a greater sensitivity than binned methods. Preliminary studies have been made using the three body decays $D^0 \\rightarrow K_\\rm{S}^0 \\pi^+ \\pi^-$ and $D^0 \\rightarrow \\pi^+ \\pi^- \\pi^0$, which is especially challenging since there is one neutral particle in each of the final states. An attempt to visualise where CP violation occurs in Dalitz plots is also presented.
Atomic Color Superfluid via Three-Body Loss
International Nuclear Information System (INIS)
Kantian, A.; Diehl, S.; Zoller, P.; Daley, A. J.; Dalmonte, M.; Hofstetter, W.
2009-01-01
Large three-body loss rates in a three-component Fermi gas confined in an optical lattice can dynamically prevent atoms from tunneling so as to occupy a lattice site with three atoms. This effective constraint not only suppresses the occurrence of actual loss events, but stabilizes BCS-pairing phases by suppressing the formation of trions. We study the effect of the constraint on the many-body physics using bosonization and density matrix renormalization group techniques, and also investigate the full dissipative dynamics including loss for the example of 6 Li.
Quasi-Three Body Systems: Properties and Scattering
International Nuclear Information System (INIS)
Amusia, M. Ya.
2017-01-01
We investigate systems of three mutually interacting particles with masses m e , m μ , M that obey the following inequality m e ≪ m μ ≪ M. Then the three-body problem reduces to the two-body scattering or structure of m e in the field of the pseudo-nucleus m μ M. We calculate analytically the properties of considered systems, such as the scattering cross-sections, hyperfine splitting, Auger decay of exited states and Lamb shifts, presenting them as expansions in powers of the parameter β=m e /m μ ≪1. (author)
Three-body cluster state in 11B
International Nuclear Information System (INIS)
Kawabata, T.; Akimune, H.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Hara, K.; Hatanaka, K.; Itoh, M.; Kanada-En'yo, Y.; Kishi, S.; Nakanishi, K.; Sakaguchi, H.; Shimbara, Y.; Tamii, A.; Terashima, S.; Uchida, M.; Wakasa, T.; Yasuda, Y.; Yoshida, H.P.; Yosoi, M.
2007-01-01
The cluster structures of the excited states in 11 B are studied by analyzing the isoscalar monopole and quadrupole strengths in the 11 B(d,d ' ) reaction at E d =200 MeV. The excitation strengths are compared with the predictions by the shell-model and antisymmetrized molecular-dynamics (AMD) calculations. It is found that the large monopole strength for the 3/2 3 - state at E x =8.56 MeV is well described by the AMD calculation and is an evidence for a developed three-body 2α+t cluster structure
The three-body problem in quantum mechanics
International Nuclear Information System (INIS)
Antunes, A.C.B.
1973-01-01
Different methods used in the analysis of the scattering of an elementary particle by a system of two bound particles are compared. All particles are considered spinless and distinguishable from each other. Two approaches are used in the treatment of the problem. In the first method we build an effective - potential which accounts for the interaction of the incident particle with the bound system. The second approach consists in treating the target as a system of two particles, whose momentum distribution is given by the bound state wavefunction. The three body system is then treated by the techniques of the multiple scattering series and of Glauber theory. (author)
Kalampounias, Angelos G.; Papatheodorou, George N.
2018-06-01
Temperature dependent Raman spectra of boric oxide have been measured in a temperature range covering the glassy, supercooled and liquid state. The shift of the isotropic band assigned to boroxol rings relative to the anisotropic component upon heating the glass is measured and attributed to the Raman non-coincidence effect. The measured shift is associated with the competition between attraction and repulsion forces with increasing temperature. The relation of dephasing and orientational relaxation times to the non-coincidence effect of the condensed phases has been examined. We discuss our results in the framework of the current phenomenological status of the field in an attempt to separate the attraction and repulsion contributions corresponding to the observed non-coincidence effect.
New results on order and spacing of levels for two- and three-body systems
International Nuclear Information System (INIS)
Grosse, H.; Martin, A.; Richard, J.M.; Taxil, P.
1987-01-01
The authors propose sufficient conditions on the potential binding a two-body system to compare; the energy of a state with angular momentum iota+1 to the average of the energies of the neighbouring states with angular momentum iota, the spacings of the successive iota = O excitations. Applications to quarkonium physics are given. The authors also find a condition giving the sign of the parameter Δ controlling the pattern of levels obtained by perturbing the lowest positive parity excitation of a three-body system bound by harmonic oscillator two body forces
Mitri, F. G.
2017-11-01
The acoustic radiation forces arising on a pair of sound impenetrable cylindrical particles of arbitrary cross-sections are derived. Plane progressive, standing or quasi-standing waves with an arbitrary incidence angle are considered. Multiple scattering effects are described using the multipole expansion formalism and the addition theorem of cylindrical wave functions. An effective incident acoustic field on a particular object is determined, and used with the scattered field to derive closed-form analytical expressions for the radiation force vector components. The mathematical expressions for the radiation force components are exact, and have been formulated in partial-wave series expansions in cylindrical coordinates involving the angle of incidence, the reflection coefficient forming the progressive or the (quasi)standing wave field, the addition theorem, and the expansion coefficients. Numerical examples illustrate the analysis for two rigid circular cross-sections immersed in a non-viscous fluid. Computations for the dimensionless radiation force functions are performed with emphasis on varying the angle of incidence, the interparticle distance, the sizes of the particles as well as the characteristics of the incident field. Depending on the interparticle distance and angle of incidence, one of the particles yields neutrality; it experiences no force and becomes unresponsive (i.e., ;invisible;) to the linear momentum transfer of the effective incident field due to multiple scattering cancellation effects. Moreover, attractive or repulsive forces between the two particles may arise depending on the interparticle distance, the angle of incidence and size parameters of the particles. This study provides a complete analytical method and computations for the axial and transverse radiation force components in multiple acoustic scattering encompassing the cases of plane progressive, standing or quasi-standing waves of arbitrary incidence by a pair of scatterers
Native Frames: Disentangling Sequential from Concerted Three-Body Fragmentation
Rajput, Jyoti; Severt, T.; Berry, Ben; Jochim, Bethany; Feizollah, Peyman; Kaderiya, Balram; Zohrabi, M.; Ablikim, U.; Ziaee, Farzaneh; Raju P., Kanaka; Rolles, D.; Rudenko, A.; Carnes, K. D.; Esry, B. D.; Ben-Itzhak, I.
2018-03-01
A key question concerning the three-body fragmentation of polyatomic molecules is the distinction of sequential and concerted mechanisms, i.e., the stepwise or simultaneous cleavage of bonds. Using laser-driven fragmentation of OCS into O++C++S+ and employing coincidence momentum imaging, we demonstrate a novel method that enables the clear separation of sequential and concerted breakup. The separation is accomplished by analyzing the three-body fragmentation in the native frame associated with each step and taking advantage of the rotation of the intermediate molecular fragment, CO2 + or CS2 + , before its unimolecular dissociation. This native-frame method works for any projectile (electrons, ions, or photons), provides details on each step of the sequential breakup, and enables the retrieval of the relevant spectra for sequential and concerted breakup separately. Specifically, this allows the determination of the branching ratio of all these processes in OCS3 + breakup. Moreover, we find that the first step of sequential breakup is tightly aligned along the laser polarization and identify the likely electronic states of the intermediate dication that undergo unimolecular dissociation in the second step. Finally, the separated concerted breakup spectra show clearly that the central carbon atom is preferentially ejected perpendicular to the laser field.
Covariant equations for the three-body bound state
International Nuclear Information System (INIS)
Stadler, A.; Gross, F.; Frank, M.
1997-01-01
The covariant spectator (or Gross) equations for the bound state of three identical spin 1/2 particles, in which two of the three interacting particles are always on shell, are developed and reduced to a form suitable for numerical solution. The equations are first written in operator form and compared to the Bethe-Salpeter equation, then expanded into plane wave momentum states, and finally expanded into partial waves using the three-body helicity formalism first introduced by Wick. In order to solve the equations, the two-body scattering amplitudes must be boosted from the overall three-body rest frame to their individual two-body rest frames, and all effects which arise from these boosts, including Wigner rotations and p-spin decomposition of the shell-particle, are treated exactly. In their final form, the equations reduce to a coupled set of Faddeev-like double integral equations with additional channels arising from the negative p-spin states of the off-shell particle
International Nuclear Information System (INIS)
Bonitz, M; Pehlke, E; Schoof, T
2013-01-01
In a recent paper (Shukla et al 2013 Phys. Scr. 87 018202) the authors criticized our analysis of the screened proton potential in dense hydrogen that was based on ab initio density functional theory (DFT) simulations (Bonitz et al 2013 Phys. Rev. E 87 037102). In particular, they attributed the absence of the Shukla–Eliasson attractive force between protons in the DFT simulations to a failure of DFT. Here we discuss in detail their arguments and show that their conclusions are incorrect. (comment)
Nuclear structure with unitarily transformed two-body plus phenomenological three-body interactions
Energy Technology Data Exchange (ETDEWEB)
Guenther, Anneke
2011-02-02
The importance of three-nucleon forces for a variety of nuclear structure phenomena is apparent in various investigations. This thesis provides a first step towards the inclusion of realistic three-nucleon forces by studying simple phenomenological threebody interactions. The Unitary Correlation Operator Method (UCOM) and the Similarity Renormalization Group (SRG) provide two different approaches to derive soft phase-shift equivalent nucleon-nucleon (NN) interactions via unitary transformations. Although their motivations are quite different the NN interactions obtained with the two methods exhibit some similarities. The application of the UCOM- or SRG-transformed Argonne V18 potential in the Hartree-Fock (HF) approximation and including the second-order energy corrections emerging from many-body perturbation theory (MBPT) reveals that the systematics of experimental ground-state energies can be reproduced by some of the interactions considering a series of closed-shell nuclei across the whole nuclear chart. However, charge radii are systematically underestimated, especially for intermediate and heavy nuclei. This discrepancy to experimental data is expected to result from neglected three-nucleon interactions. As first ansatz for a three-nucleon force, we consider a finite-range three-body interaction of Gaussian shape. Its influence on ground-state energies and charge radii is discussed in detail on the basis of HF plus MBPT calculations and shows a significant improvement in the description of experimental data. As the handling of the Gaussian three-body interaction is time-extensive, we show that it can be replaced by a regularized three-body contact interaction exhibiting a very similar behavior. An extensive study characterizes its properties in detail and confirms the improvements with respect to nuclear properties. To take into account information of an exact numerical solution of the nuclear eigenvalue problem, the No-Core Shell Model is applied to
Three-body continuum states on a Lagrange mesh
International Nuclear Information System (INIS)
Descouvemont, P.; Tursunov, E.; Baye, D.
2006-01-01
Three-body continuum states are investigated with the hyperspherical method on a Lagrange mesh. The R-matrix theory is used to treat the asymptotic behaviour of scattering wave functions. The formalism is developed for neutral as well as for charged systems. We point out some specificities of continuum states in the hyperspherical method. The collision matrix can be determined with a good accuracy by using propagation techniques. The method is applied to the 6 He (=α+n+n) and 6 Be (=α+p+p) systems, as well as to 14 Be (=Be12+n+n). For 6 He, we essentially recover results of the literature. Application to 14 Be suggests the existence of an excited 2 + state below threshold. The calculated B(E2) value should make this state observable with Coulomb excitation experiments
Three-body recombination of cold fermionic atoms
International Nuclear Information System (INIS)
Suno, H; Esry, B D; Greene, Chris H
2003-01-01
Recombination of identical, spin-polarized fermions in cold three-body collisions is investigated. We parametrize the mechanisms for recombination in terms of the 'scattering volume' V p and another length scale r 0 . Model two-body interactions were used within the framework of the adiabatic hyperspherical representation. We examine the recombination rate K 3 as a function of the collision energy E for various values of V p . Not only do we consider the dominant J Π = 1 + case, but also the next-leading order contributions from J Π = 1 - and 3 - . We discuss the behaviour near a two-body resonance and the expected universality of fermionic recombination. Comparisons with boson recombination are considered in detail
Generating families in the restricted three-body problem
Hénon, Michel
The classical restricted three-body problem is of fundamental importance because of its applications in astronomy and space navigation, and also as a simple model of a non-integrable Hamiltonian dynamical system. A central role is played by periodic orbits, of which many have been computed numerically. This is the second volume of an attempt to explain and organize the material through a systematic study of generating families, the limits of families of periodic orbits when the mass ratio of the two main bodies becomes vanishingly small. We use quantitative analysis in the vicinity of bifurcations of types 1 and 2. In most cases the junctions between branches can now be determined. A first-order approximation of families of periodic orbits in the vicinity of a bifurcation is also obtained. This book is intended for scientists and students interested in the restricted problem, in its applications to astronomy and space research, and in the theory of dynamical systems.
Three body mechanisms in hadron collisions. The A = 3 system
International Nuclear Information System (INIS)
Frascaria, R.
1988-01-01
Three-body mechanisms in hadron collisions, and the role of the A = 3 system are reviewed, and the excitation functions of the proton deuteron system in interactions at energies up to 2.9 GeV are discussed. Meson productions at large angles reveal structures due to the mesonic degrees of freedom in the interaction of the proton with the deuteron, exciting n * isobars in intermediate states. Propagation in the nuclei does not seem to change the properties of these isobars. The meson double scattering mechanism provides a way to understand coherent meson production in pd capture. It is difficult to say whether this coherent process corresponds to eigenstates of the A = 3 system. The sharing of the momentum transfer between the three nucleons renders impossible the observation of high momentum components in coherent proton captures. The possible contribution of the electromagnetic probe in hadron physics with a multi GeV electron accelerator is mentioned
Relativistic three-body effects in black hole coalescence
International Nuclear Information System (INIS)
Campanelli, Manuela; Dettwyler, Miranda; Lousto, Carlos O.; Hannam, Mark
2006-01-01
Three-body interactions are expected to be common in globular clusters and in galactic cores hosting supermassive black holes. We consider an equal-mass binary black hole system in the presence of a third black hole. Using numerically generated binary black hole initial data sets, and first and second-order post-Newtonian (1PN and 2PN) techniques, we find that the presence of the third black hole has non-negligible relativistic effects on the location of the binary's innermost stable circular orbit (ISCO), and that these effects arise at 2PN order. For a stellar-mass black hole binary in orbit about a supermassive black hole, the massive black hole has stabilizing effects on the orbiting binary, leading to an increase in merger time and a decrease of the terminal orbital frequency, and an amplification of the gravitational radiation emitted from the binary system by up to 6%
Three-body problem in the ground-state representation
International Nuclear Information System (INIS)
Gonzalez, A.
1993-01-01
The ground-state probability density of a three-body system is used to construct a classical potential U whose minimum coincides exactly with the ground-state energy. The spectrum of excited states may approximately be obtained by imposing quasiclassical quantization conditions over the classical motion in U. We show nontrivial one-dimensional models in which either this quantization condition is exact or considerably improves the usual semiclassical quantization. For three-dimensional problems, the small-oscillation frequencies in states with total angular momentum L = 0 are computed. These frequencies could represent an improvement over the frequencies of triatomic molecules computed with the use of ordinary quasiclassics for the motion of the nuclei in the molecular term. By providing a semiclassical description of the first excited quantum states, the sketched approach rises some interesting questions such as, for example, the relevance (once again) of classical chaos to quantum mechanics
Three body dynamics and its applications to exoplanets
Musielak, Zdzislaw
2017-01-01
This brief book provides an overview of the gravitational orbital evolution of few-body systems, in particular those consisting of three bodies. The authors present the historical context that begins with the origin of the problem as defined by Newton, which was followed up by Euler, Lagrange, Laplace, and many others. Additionally, they consider the modern works from the 20th and 21st centuries that describe the development of powerful analytical methods by Poincare and others. The development of numerical tools, including modern symplectic methods, are presented as they pertain to the identification of short-term chaos and long term integrations of the orbits of many astronomical architectures such as stellar triples, planets in binaries, and single stars that host multiple exoplanets. The book includes some of the latest discoveries from the Kepler and now K2 missions, as well as applications to exoplanets discovered via the radial velocity method. Specifically, the authors give a unique perspective in rel...
Unitary three-body calculation of nucleon-nucleon scattering
International Nuclear Information System (INIS)
Tanabe, H.; Ohta, K.
1986-07-01
We calculate nucleon-nucleon elastic scattering phase parameters based on a unitary, relativistic, pion-exchange model. The results are highly dependent on the off-shell amplitudes of πN scattering. The isobar-dominated model for the P 33 interaction leads to too small pion production rates owing to its strong suppression of off-shell pions. We propose to expand the idea of the Δ-isobar model in such a manner as to incorporate a background (non-pole) interaction. The two-potential model, which was first applied to the P 11 partial wave by Mizutani and Koltun, is applied also to the P 33 wave. Our phenomenological model for πN interaction in the P 33 partial wave differs from the conventional model only in its off-shell extrapolation, and has two different variants for the πN → Δ vertex. The three-body approach of Kloet and Silbar is extended such that the background interactions can be included straightfowardly. We make detailed comparisons of the new model with the conventional one and find that our model adequately reproduces the 1 D 2 phase parameters as well as those of peripheral partial waves. We also find that the longitudinal total cross section difference Δσ L (pp → NNπ) comes closer to the data compared to Kloet and Silbar. We discuss about the backward pion propagation in the three-body calculation, and the Pauli-principle violating states for the background P 11 interaction. (author)
Three-body model of deuteron breakup and stripping, II
International Nuclear Information System (INIS)
Austern, N.; Vincent, C.M.; Farrell, J.P. Jr.
1978-01-01
A previously investigated three-body model of the deuteron-nucleus system, limited to relative angular momentum l=0 for the two active nucleons, is reevaluated. Full attention is given to self-consistency between elastic and breakup channels. Introduction of the reaction of breakup on the elastic channel now reduces the elastic reflection coefficients in low partial waves by nearly a factor of 2 and causes substantial shifts in phase. Breakup amplitudes in low partial waves are also greatly reduced. As before, the breakup part of the wavefunction contains a broad specteum of n-p continuum states. The breakup part of the wavefunction at zero n-p separation is localized at small radii, within and just outside the target nucleus, where it is comparable in magnitude with the projected elastic channel wavefunction. As a result, the projected elastic channel wavefuntion is a poor approximation to the full wavefunction at n-p coincidence. Deuteron stripping theories that use the projected elastic wavefunction in a truncated distorted waves Born series must correspondingly be quite misleading. To investigate deuteron stripping further, the exact result of the coupled channels calculation is compared with several standard approximate models. Although there is a close qualitative resemblance among the results of all the approaches, the best single approximation to the coupled channels result is found from the familiar phenomenological approach, in which a local optical potential is fitted to the elastic scattering ''observed'' in the coupled channels calculation. The coupled channels results are also used to analyze the approximations in the Johnson-Soper method. Several formal aspects of the three-body model are discussed
2015-10-25
Graduation Requirements Advisors: Dr . Gregory F. Intoccia and Dr . Patricia Lessane Maxwell Air Force Base, Alabama 25 October 2015 DISTRIBUTION A...support while I was diverting much of my free time and attention to this graduate program. I appreciate my research advisors Dr . Greg Intoccia and Dr ...underutilized USAJOBS, the federal government job search engine, as compare to LinkedIn , Career Builders and Monster. Only 8.8 percent of the
Three-body calculation of Be double- hypernuclei
Indian Academy of Sciences (India)
an intermediate sigma; and hyperon–nucleon–nucleon forces that may be relatively more important than three-nucleon forces, depending on whether sigmas are kept explicitly. So far, several cluster models have been proposed to estimate the ground-state bind- ing energies of double- species [1–6]. Recently,.
Silva Lopez, Carlos; Nieto Faza, Olalla; De Proft, Frank; Kolocouris, Antonios
2016-11-15
The interactions of axial substituents in monosubstituted cyclohexane rings are studied in this work using an array of different computational techniques. Additionally, the anomalous axial preference for some bulky substituents is related to stabilizing dispersion interactions. We find that the C-H ax ···Y ax contacts for various substituents with distances ranging from 2 to ∼5 Å may include attractive dispersion forces that can affect the conformational equilibrium; these forces co-exist with Pauli repulsive forces effected by Y ax group due to van der Waals sphere penetration. At distances between 2 and 3 Å stabilizing electron transfer interactions were calculated and the combination of natural bond orbital and QTAIM analysis showed that, in certain cases, Y ax = t Bu, C ax -O or C ax = O or S ax = O or C ax = S this interaction can be characterized as an improper H-bond. DFT-D3 and non-covalent interactions calculations (NCIs) in cyclohexane derivatives with Y ax = SiOR 3 including H Yax ···H cy surfaces at distances ranging between 4 and 6 Å suggest that dispersion has a clear effect on the experimentally observed stabilization of the axial conformer. NCIs computed from the reduced density gradient help to visually identify and analyze these interactions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Free time minimizers for the three-body problem
Moeckel, Richard; Montgomery, Richard; Sánchez Morgado, Héctor
2018-03-01
Free time minimizers of the action (called "semi-static" solutions by Mañe in International congress on dynamical systems in Montevideo (a tribute to Ricardo Mañé), vol 362, pp 120-131, 1996) play a central role in the theory of weak KAM solutions to the Hamilton-Jacobi equation (Fathi in Weak KAM Theorem in Lagrangian Dynamics Preliminary Version Number 10, 2017). We prove that any solution to Newton's three-body problem which is asymptotic to Lagrange's parabolic homothetic solution is eventually a free time minimizer. Conversely, we prove that every free time minimizer tends to Lagrange's solution, provided the mass ratios lie in a certain large open set of mass ratios. We were inspired by the work of Da Luz and Maderna (Math Proc Camb Philos Soc 156:209-227, 1980) which showed that every free time minimizer for the N-body problem is parabolic and therefore must be asymptotic to the set of central configurations. We exclude being asymptotic to Euler's central configurations by a second variation argument. Central configurations correspond to rest points for the McGehee blown-up dynamics. The large open set of mass ratios are those for which the linearized dynamics at each Euler rest point has a complex eigenvalue.
Global regularization method for planar restricted three-body problem
Directory of Open Access Journals (Sweden)
Sharaf M.A.
2015-01-01
Full Text Available In this paper, global regularization method for planar restricted three-body problem is purposed by using the transformation z = x+iy = ν cos n(u+iv, where i = √−1, 0 < ν ≤ 1 and n is a positive integer. The method is developed analytically and computationally. For the analytical developments, analytical solutions in power series of the pseudotime τ are obtained for positions and velocities (u, v, u', v' and (x, y, x˙, y˙ in both regularized and physical planes respectively, the physical time t is also obtained as power series in τ. Moreover, relations between the coefficients of the power series are obtained for two consequent values of n. Also, we developed analytical solutions in power series form for the inverse problem of finding τ in terms of t. As typical examples, three symbolic expressions for the coefficients of the power series were developed in terms of initial values. As to the computational developments, the global regularized equations of motion are developed together with their initial values in forms suitable for digital computations using any differential equations solver. On the other hand, for numerical evolutions of power series, an efficient method depending on the continued fraction theory is provided.
Analytic scattering theory of quantum mechanical three-body systems
International Nuclear Information System (INIS)
Balslev, Erik
1980-01-01
We consider a three-body Schroedinger operator H=H 0 +V in L 2 (Rsup(2n)), where V=Σ Vsub(α) and each Vsub(α) is a dilation-analytic two-body interaction decreasing faster than rsup(-β), where β>1 for negative energies and β>2 for positive energies. Together with H we consider the associated self-adjoint analytic family of operator given in momentum space by H(z)=z 2 H 0 +V(z), /Arg z/ 0 , H). The local inverse wave operators are constructed and asymptotic completeness proved. The full S-matrix S(μ) and for phi not equal to 0 the channel S-matrices are expressed in terms of boundary values of the resolvent. It is proved that the function is an analytic continuation into the lower half-plane of the diagonal element with poles at most at resolvent resonances and, under some reasonable assumptions, precisely at these resonances
EJECTION AND CAPTURE DYNAMICS IN RESTRICTED THREE-BODY ENCOUNTERS
International Nuclear Information System (INIS)
Kobayashi, Shiho; Hainick, Yanir; Sari, Re'em; Rossi, Elena M.
2012-01-01
We study the tidal disruption of binaries by a massive point mass (e.g., the black hole at the Galactic center), and we discuss how the ejection and capture preference between unequal-mass binary members depends on which orbit they approach the massive object. We show that the restricted three-body approximation provides a simple and clear description of the dynamics. The orbit of a binary with mass m around a massive object M should be almost parabolic with an eccentricity of |1 – e| ∼ 1/3 1/3 times the binary rotation velocity, it would be abruptly disrupted, and the energy change at the encounter can be evaluated in a simple disruption model. We evaluate the probability distributions for the ejection and capture of circular binary members and for the final energies. In principle, for any hyperbolic (elliptic) orbit, the heavier member has more chance to be ejected (captured), because it carries a larger fraction of the orbital energy. However, if the orbital energy is close to zero, the difference between the two members becomes small, and there is practically no ejection and capture preferences. The preference becomes significant when the orbital energy is comparable to the typical energy change at the encounter. We discuss its implications to hypervelocity stars and irregular satellites around giant planets.
Energy Analysis in the Elliptic Restricted Three-body Problem
Qi, Yi; de Ruiter, Anton
2018-05-01
The gravity assist or flyby is investigated by analyzing the inertial energy of a test particle in the elliptic restricted three-body problem (ERTBP), where two primary bodies are moving in elliptic orbits. Firstly, the expression of the derivation of energy is obtained and discussed. Then, the approximate expressions of energy change in a circular neighborhood of the smaller primary are derived. Numerical computation indicates that the obtained expressions can be applied to study the flyby problem of the nine planets and the Moon in the solar system. Parameters related to the flyby are discussed analytically and numerically. The optimal conditions, including the position and time of the periapsis, for a flyby orbit are found to make a maximum energy gain or loss. Finally, the mechanical process of a flyby orbit is uncovered by an approximate expression in the ERTBP. Numerical computations testify that our analytical results well approximate the mechanical process of flyby orbits obtained by the numerical simulation in the ERTBP. Compared with the previous research established in the patched-conic method and numerical calculation, our analytical investigations based on a more elaborate derivation get more original results.
Shell structure of the A = 6 ground states from three-body dynamics
International Nuclear Information System (INIS)
Lehman, D.R.; Parke, W.C.
1983-01-01
Three-body (αNN) models of the 6 He and 6 Li ground states are used to investigate their shell structure. Three models for each nucleus are considered: simple, full (nn), and full (np) for 6 He, and simple, full (0%), and full (4%) for 6 Li. The full models in both cases are obtained by including the S/sub 1/2/, P/sub 1/2/, and P/sub 3/2/ partial waves of the αN interaction, whereas the simple model truncates to only the strongly resonant P/sub 3/2/ wave. The 6 He full models distinguish between use of the nn or np parameters for the 1 S 0 NN interaction, while the 6 Li full models have either a pure 3 S 1 NN interaction (0%) or a 3 S 1 - 3 D 1 interaction that leads to a 4% d-wave component in the deuteron (4%). These models are used to calculate the probabilities of the orbital components of the wave functions, the configuration-space single-particle orbital densities, and the configuration-space two-particle wave function amplitudes in j-j coupling with the nucleon coordinates referred to the alpha particle as the ''core'' or ''center of force.'' The results are then compared with those from phenomenological and realistic-interaction shell models. Major findings of the comparison are the following: None of the shell models considered have a distribution of orbital probabilities across shells like that predicted by three-body models; the orbital rms radii from three-body models indicate an ordering of the orbits within shells, i.e., p/sub 1/2/ outside p/sub 3/2/, unlike oscillator shell models with a single oscillator parameter where the p-shell orbitals have the same shape; and, as expected, three-body orbital densities decay at large radial distances as exponentials rather than the too compact Gaussian falling off of oscillator shell models
Three-body halo nuclei in an effective theory framework
Energy Technology Data Exchange (ETDEWEB)
Canham, David L.
2009-05-20
The universal properties and structure of halo nuclei composed of two neutrons (2n) and a core are investigated within an effective quantum mechanics framework. We construct an effective interaction potential that exploits the separation of scales in halo nuclei and treat the nucleus as an effective three-body system, which to leading order is described by the large S-wave scattering lengths in the underlying two-body subsystems. The uncertainty from higher orders in the expansion is quantified through theoretical error bands. First, we investigate the possibility to observe excited Efimov states in 2n halo nuclei. Based on the experimental data, {sup 20}C is the only halo nucleus candidate to possibly have an Efimov excited state, with an energy less than 7 keV below the scattering threshold. Second, we study the structure of {sup 20}C and other 2n halo nuclei. In particular, we calculate their matter density form factors, radii, and two-neutron opening angles. We then make a systematic improvement upon these calculations by extending the effective potential to the next-to-leading order. To this order, we require an additional two-body parameter, which we tune to the effective range of the interaction. In addition to range corrections to the 2n halo nuclei results, we show corrections to the Efimov effect in the three-boson system. Furthermore, we explore universality in the linear range corrections to the Efimov spectrum. Finally, we study the scattering of D{sup 0} and D{sup *0} mesons and their antiparticles off the X(3872) in an effective field theory for short-range interactions. We present results for the S-wave scattering amplitude, total interaction cross section and S-wave scattering length. (orig.)
Three Body Decays of D0 and DS Mesons
International Nuclear Information System (INIS)
Palano, Antimo
2001-01-01
New generation experiments are providing large data sets for charm physics with statistics which supersede most previous measurements. The Dalitz plot analyses of 3-body charm decays have been performed in the past but these new large and clean samples will allow high precision measurements that were never before possible. The Dalitz plot analysis of three-body decays is a relatively new technique in development for charm physics studies. This method of analysis is the most complete way of analyzing the data since it allows measurement of both decay amplitudes and phases. The final state is the result of the interference of all intermediate states. The significant results provided by these studies are: (1) Accurate measurements of branching fractions; (2) A study of Final State Interactions; (3) A study of CP violation in rates and decay amplitudes; and (4) New input to several old unsolved problems in light meson spectroscopy, in particular to the scalar mesons puzzle. Factorization models assume the weak decay amplitudes to be real. The fact that the observed amplitudes have a relative complex phase is a consequence of final state interaction. CP violation is expected to be small in charm decays (∼ 10 -3 ) [1]. Two amplitudes with different phases are needed: Ae iδA + Be iδB . In singly Cabibbo-suppressed decays penguin terms may provide a weak phase, while Final State Interactions provide a strong phase shift. Under CP the weak phases change sign but the strong ones do not. Any difference between D and (bar D) in the Dalitz plot would be evidence for CP violation. Throughout this paper charge conjugate modes, where not explicit, are implied
Three-body halo nuclei in an effective theory framework
International Nuclear Information System (INIS)
Canham, David L.
2009-01-01
The universal properties and structure of halo nuclei composed of two neutrons (2n) and a core are investigated within an effective quantum mechanics framework. We construct an effective interaction potential that exploits the separation of scales in halo nuclei and treat the nucleus as an effective three-body system, which to leading order is described by the large S-wave scattering lengths in the underlying two-body subsystems. The uncertainty from higher orders in the expansion is quantified through theoretical error bands. First, we investigate the possibility to observe excited Efimov states in 2n halo nuclei. Based on the experimental data, 20 C is the only halo nucleus candidate to possibly have an Efimov excited state, with an energy less than 7 keV below the scattering threshold. Second, we study the structure of 20 C and other 2n halo nuclei. In particular, we calculate their matter density form factors, radii, and two-neutron opening angles. We then make a systematic improvement upon these calculations by extending the effective potential to the next-to-leading order. To this order, we require an additional two-body parameter, which we tune to the effective range of the interaction. In addition to range corrections to the 2n halo nuclei results, we show corrections to the Efimov effect in the three-boson system. Furthermore, we explore universality in the linear range corrections to the Efimov spectrum. Finally, we study the scattering of D 0 and D *0 mesons and their antiparticles off the X(3872) in an effective field theory for short-range interactions. We present results for the S-wave scattering amplitude, total interaction cross section and S-wave scattering length. (orig.)
Universal Three-Body Physics in Ultracold KRb Mixtures
DEFF Research Database (Denmark)
Wacker, L. J.; Jørgensen, N. B.; Birkmose, Danny Matthiesen
2016-01-01
Ultracold atomic gases have recently become a driving force in few-body physics due to the observation of the Efimov effect. While initially observed in equal mass systems, one expects even richer few-body physics in the mass-imbalanced case. In previous experiments with ultracold mixtures of pot...
Directory of Open Access Journals (Sweden)
Stefan Thurner
Full Text Available Physical interactions between particles are the result of the exchange of gauge bosons. Human interactions are mediated by the exchange of messages, goods, money, promises, hostilities, etc. While in the physical world interactions and their associated forces have immediate dynamical consequences (Newton's laws the situation is not clear for human interactions. Here we quantify the relative acceleration between humans who interact through the exchange of messages, goods and hostilities in a massive multiplayer online game. For this game we have complete information about all interactions (exchange events between about 430,000 players, and about their trajectories (movements in the metric space of the game universe at any point in time. We use this information to derive "interaction potentials" for communication, trade and attacks and show that they are harmonic in nature. Individuals who exchange messages and trade goods generally attract each other and start to separate immediately after exchange events end. The form of the interaction potential for attacks mirrors the usual "hit-and-run" tactics of aggressive players. By measuring interaction intensities as a function of distance, velocity and acceleration, we show that "forces" between players are directly related to the number of exchange events. We find an approximate power-law decay of the likelihood for interactions as a function of distance, which is in accordance with previous real world empirical work. We show that the obtained potentials can be understood with a simple model assuming an exchange-driven force in combination with a distance-dependent exchange rate.
Three-Body Potentials in α-Particle Model of Light Nuclei
International Nuclear Information System (INIS)
Ishikawa, Souichi
2017-01-01
In three-body model calculations of atomic nuclei, e.g., the "1"2C nucleus as α-α-α system and the "9Be nucleus as α-α-n system, the Hamiltonians of the systems consisting of two- and three-body potentials are important inputs. However, our knowledge of three-body potentials is quite restricted. In this paper, I will examine a relation between α-α-α and α-α-n three-body potentials that is obtained in a simple cluster model picture, which gives a phenomenological constraint condition on the three-body potential models to be used. (author)
Nucleon-nucleon scattering length from three-body reactions
International Nuclear Information System (INIS)
Bodek, K.
1989-01-01
Experiments aimed at the measurement of the singlet scattering lengths 1 a np and 1 a nn of the NN-interaction in the presence of a heavy spectator are described. The values obtained are compared with the results of measurements of other reactions. The very good agreement of the experimental values of 1 a np from all breakup reactions and elastic scattering as well as agreement of the values of 1 a nn from breakup reactions and disagreement with the value from the π - d → nnγ reaction cast doubts on the hypothesis ascribing this discrepancy to a 3N-force. This result also suggests a stronger effect of a violation of the charge independence principle than previously accepted. 101 refs., 18 figs., 3 tabs. (author)
International Nuclear Information System (INIS)
Minesaki, Yukitaka
2013-01-01
For the restricted three-body problem, we propose an accurate orbital integration scheme that retains all conserved quantities of the two-body problem with two primaries and approximately preserves the Jacobi integral. The scheme is obtained by taking the limit as mass approaches zero in the discrete-time general three-body problem. For a long time interval, the proposed scheme precisely reproduces various periodic orbits that cannot be accurately computed by other generic integrators
Extended random-phase approximation with three-body ground-state correlations
International Nuclear Information System (INIS)
Tohyama, M.; Schuck, P.
2008-01-01
An extended random-phase approximation (ERPA) which contains the effects of ground-state correlations up to a three-body level is applied to an extended Lipkin model which contains an additional particle-scattering term. Three-body correlations in the ground state are necessary to preserve the hermiticity of the Hamiltonian matrix of ERPA. Two approximate forms of ERPA which neglect the three-body correlations are also applied to investigate the importance of three-body correlations. It is found that the ground-state energy is little affected by the inclusion of the three-body correlations. On the contrary, three-body correlations for the excited states can become quite important. (orig.)
Dynamics of Three-Body Correlations in Quenched Unitary Bose Gases
Colussi, V. E.; Corson, J. P.; D'Incao, J. P.
2018-03-01
We investigate dynamical three-body correlations in the Bose gas during the earliest stages of evolution after a quench to the unitary regime. The development of few-body correlations is theoretically observed by determining the two- and three-body contacts. We find that the growth of three-body correlations is gradual compared to two-body correlations. The three-body contact oscillates coherently, and we identify this as a signature of Efimov trimers. We show that the growth of three-body correlations depends nontrivially on parameters derived from both the density and Efimov physics. These results demonstrate the violation of scaling invariance of unitary bosonic systems via the appearance of log-periodic modulation of three-body correlations.
FaCE: a tool for Three Body Faddeev calculations with core excitation
Thompson, I. J.; Nunes, F. M.; Danilin, B. V.
2004-01-01
FaCE is a self contained programme, with namelist input, that solves the three body Faddeev equations. It enables the inclusion of excitation of one of the three bodies, whilst the other two remain inert. It is particularly useful for obtaining the binding energies and bound state structure compositions of light exotic nuclei treated as three-body systems, given the three effective two body interactions. A large variety of forms for these interactions may be defined, and supersymmetric transf...
Directory of Open Access Journals (Sweden)
Daniel Farrelly
2007-04-01
Full Text Available Explaining human cooperation continues to present a challenge because it goes beyond what is predicted by established theories of kinship and reciprocal altruism. Little attention has been paid to the sexual selection hypothesis that proposes that cooperation can act as a display that attracts mates. The costs of cooperating are then offset not by kinship or reciprocation but by increased mating success. Here we present results from a series of experiments which show that, as predicted by the sexual selection hypothesis, people preferentially direct cooperative behavior towards more attractive members of the opposite sex. Furthermore, cooperative behavior increases the perceived attractiveness of the cooperator. Economically costly behaviors can therefore bring benefits through mate choice and sexual selection should be regarded as an evolutionary mechanism capable of promoting cooperation.
Three-body forces, relativistic effects, isobars, and pions in nuclear systems
International Nuclear Information System (INIS)
Wiringa, R.B.
1983-01-01
Conventional microscopic calculations in nuclear physics start from a nonrelativistic Hamiltonian. The many-body Schroedinger equation is then solved to obtain the ground state energy, wave function, and expectation values of other quantities of interest. Such a procedure gives a qualitative description of nuclear saturation properties, but it is now well established that the simple H is quantitatively inadequate. For example, the light nuclei are underbound with too large a charge radius, while nuclear matter is overbound at far too high a density. This note reviews recent studies that go beyond the simple H. These include 1) the introduction of three-nucleon potentials, 2) estimates of relativistic effects, 3) the introduction of isobar degrees of freedom in the two-body potential, and 4) probing the influence of pion degrees of freedom on nuclear systems
Three-body Coulomb systems using generalized angular-momentum S states
Whitten, R. C.; Sims, J. S.
1974-01-01
An expansion of the three-body Coulomb potential in generalized angular-momentum eigenfunctions developed earlier by one of the authors is used to compute energy eigenvalues and eigenfunctions of bound S states of three-body Coulomb systems. The results for He, H(-), e(-)e(+)e(-), and pmu(-)p are compared with the results of other computational approaches.
DEFF Research Database (Denmark)
Jensen, Kim Ebensgaard
2012-01-01
The purpose of this paper is two-fold. Firstly, it presents an argument for usage-based inheritance models over complete inheritance models in construction grammar. It is argued that, with the principle of inductive language learning as their foundation, usage-based inheritance models allow...... for redundancies and incongruities in construction networks which enables linguists to take into account details of language use, which would otherwise not be facilitated in complete inheritance models. Secondly, making use of the method of collostructional analysis, the article offers a corpus-based description...... of the use of the Danish ihjel-construction which accounts for patterns of attraction of construction-verb attraction, patterns of productivity, and various types of subconstructions, including item- and item-class-based ones and metaphorical extensions. The description of the ihjel-construction should also...
Evolved chiral Hamiltonians at the three-body level and beyond
Energy Technology Data Exchange (ETDEWEB)
Calci, Angelo
2014-07-14
Based on the fundamental symmetries of QCD, chiral effective field theory (EFT) provides two- (NN), three- (3N), four- (4N), and many-nucleon interactions in a consistent and systematic scheme. Recent developments to construct chiral NN+3N interactions at different chiral orders and regularizations enable exciting nuclear structure investigations as well as a quantification of the fundamental uncertainties resulting from the chiral expansion and regularization. We present the complete toolchain to employ the present and future chiral NN, 3N, and 4N interactions in nuclear structure calculations and emphasize technical developments in the three- and four-body space, such as the similarity renormalization group (SRG), the frequency conversion, and the transformation to the JT-coupled scheme. We study the predictions of the chiral NN+3N interactions in ab initio nuclear structure calculations with the importance-truncated no-core shell model and coupled-cluster approach. We demonstrate that the inclusion of chiral 3N forces improves the overall agreement with experiment for excitation energies of p-shell nuclei and it qualitatively reproduces the systematics of nuclear binding energies throughout the nuclear chart up to heavy tin isotopes. In this context it is necessary to introduce truncations in the three-body model space and we carefully analyze their impact and confirm the reliability of the reported results. The SRG evolution induces many-nucleon forces that generally cannot be included in the calculations and constitute a major limitation for the applicability of SRG-evolved chiral forces. We study the origin and effect of the induced many-nucleon forces and propose a modification of the interaction, which suppresses the induced beyond-3N forces. This enables applications of the chiral interactions far beyond the mid-p shell. Furthermore, we test alternative formulations of SRG generators aiming to prevent the induced many-body forces from the outset. The
Three-body Coulomb breakup of 11Li in the complex scaling method
International Nuclear Information System (INIS)
Myo, Takayuki; Aoyama, Shigeyoshi; Kato, Kiyoshi; Ikeda, Kiyomi
2003-01-01
Coulomb breakup strengths of 11 Li into a three-body 9 Li+n+n system are studied in the complex scaling method. We decompose the transition strengths into the contributions from three-body resonances, two-body '' 10 Li+n'' and three-body '' 9 Li+n+n'' continuum states. In the calculated results, we cannot find the dipole resonances with a sharp decay width in 11 Li. There is a low energy enhancement in the breakup strength, which is produced by both the two- and three-body continuum states. The enhancement given by the three-body continuum states is found to have a strong connection to the halo structure of 11 Li. The calculated breakup strength distribution is compared with the experimental data from MSU, RIKEN and GSI
Effects of three-body interactions on the dynamics of entanglement in spin chains
International Nuclear Information System (INIS)
Shi Cuihua; Wu Yinzhong; Li Zhenya
2009-01-01
With the consideration of three-body interaction, dynamics of pairwise entanglement in spin chains is studied. The dependence of pairwise entanglement dynamics on the type of coupling, and distance between the spins is analyzed in a finite chain for different initial states. It is found that, for an Ising chain, three-body interactions are not in favor of preparing entanglement between the nearest neighbor spins, while three-body interactions are favorable for creating entanglement between remote spins from a separable initial state. For an isotropic Heisenberg chain, the pairwise concurrence will decrease when three-body interactions are considered both for a separable initial state and for a maximally entangled initial state, however, three-body interactions will retard the decay of the concurrence in an Ising chain when the initial state takes the maximally entangled state.
International Nuclear Information System (INIS)
Tolstikhin, Oleg I.; Namba, Chusei
2003-08-01
A program to solve the quantum-mechanical collinear three-body Coulomb problem is described and illustrated by calculations for a number of representative systems and processes. In the internal region, the Schroedinger equation is solved in hyperspherical coordinates using the slow/smooth variable discretization method. In asymptotic regions, the solution is obtained in Jacobi coordinates using the asymptotic package GAILIT from the CPC library. Only bound states and scattering processes below the three-body disintegration threshold are considered here; resonances and fragmentation processes will be discussed in subsequent parts of this series. (author)
Generalized separable expansion method of the two-body and the three-body scattering amplitudes
International Nuclear Information System (INIS)
Oryu, S.; Ishihara, T.
1976-01-01
A systematic method is proposed for obtaining new N-rank separable amplitudes of the two-body and the three-body equations. First of all, the authors start from the Amado equation which is modified from the three-body Faddeev equation by using the two-body Yamaguchi potential for the nucleon-nucleon interaction. It is well known that the Amado equation can be integrated on the real axis because the kernel has a logarithmic cut on the real axis. However, a separable three-body form factor which is regular on the real axis except for the cut has been found. (Auth.)
The d-α elastic scattering and the lithium-6 in a three-body model with separable interactions
International Nuclear Information System (INIS)
Charnomordic, Brigitte.
1976-01-01
This work consists in a three-body treatment of the six nucleon system. The model is constructed by considering two identical nucleons and a structureless alpha particle. Such a system can be described by the Faddeev-Lovelace equations. A partial antisymetrization is performed taking into account the identity of the nucleons. Pairwise interacting particles with nonlocal separable forces are introduced. Two-body potentials are chosen in each n-n and n-α partial wave. After an analysis of the existing separable interactions, new n-α and 1S0 parametrization are constructed. The sensitivity to the tensor force and the role of the N-α description are especially studied. The case of d-α elastic scattering is also discussed. The observables: differential cross-section, analyzing powers and transfer polarization coefficients are calculated and compared with experiments. The results show the ability of a three-body model with separable interactions in describing the main properties of the d-α elastic scattering and lithium-6 [fr
Sanders, Duncan A; Swift, Michael R; Bowley, R M; King, P J
2004-11-12
We present event-driven simulation results for single and multiple intruders in a vertically vibrated granular bed. Under our vibratory conditions, the mean vertical position of a single intruder is governed primarily by a buoyancylike effect. Multiple intruders also exhibit buoyancy governed behavior; however, multiple neutrally buoyant intruders cluster spontaneously and undergo horizontal segregation. These effects can be understood by considering the dynamics of two neutrally buoyant intruders. We have measured an attractive force between such intruders which has a range of five intruder diameters, and we provide a mechanistic explanation for the origins of this force.
Efimov Physics and the Three-Body Parameter within a Two-Channel Framework
DEFF Research Database (Denmark)
Sørensen, Peder Klokmose; V. Fedorov, D.; S. Jensen, A.
2012-01-01
scaling laws. We recover known results for broad Feshbach resonances with small effective range, whereas in the case of narrow resonances we find a distinct non-monotonic behavior of the threshold at which the lowest Efimov trimer merges with the three-body continuum. To address the issue of the physical...... origin of the three-body parameter we provide a physically clear model for the relation between three-body physics and typical two-body atom-atom interactions. Our results demonstrate that experimental information from narrow Feshbach resonances and/or mixed systems are of vital importance to pin down...... the relation of two- and three-body physics in atomic systems....
QED effects in high-Z atoms; three-body potentials
International Nuclear Information System (INIS)
Zygelman, B.
1983-01-01
Electromagnetic three-body potentials were first studied by Primakoff and Holstein. Later, Chamugan and Schweber rederived these potentials and pointed out that they might be important in highly relativistic systems, however, their formulation was basically nonrelativistic. Mittleman, in a series of papers, constructed configuration space equations that included three-body potentials. His derivation started from first principles i.e. QED, and the resulting three-body potentials are more general than the Primakoff-Holstein potentials. In this thesis the contribution to the binding energy of a simple high-Z ion from the three-body potentials is calculated. In addition, the nature and structure of these potentials in greater detail are studied. Some ambiguities that arise when the transition from Fock to configuration space is made are studied in detail
Multip: A Multi Purpose simulation Monte Carlo algorithm for two- and three-body reaction kinematics
Energy Technology Data Exchange (ETDEWEB)
Sgouros, O.; Soukeras, V.; Pakou, A. [The University of Ioannina, Department of Physics and HINP, Ioannina (Greece)
2017-08-15
An algorithm is proposed for the determination of inclusive or/and exclusive energy spectra for particles emitted either in two- or three-body reactions with emphasis in the dissociation of unstable particles. (orig.)
Three-body interactions in sociophysics and their role in coalition forming
Naumis, Gerardo G.; Samaniego-Steta, F.; del Castillo-Mussot, M.; Vázquez, G. J.
2007-06-01
An study of the effects of three-body interactions in the process of coalition formation is presented. In particular, we modify a spin glass model of bimodal propensities and also a Potts model in order to include a particular three-body Hamiltonian that reproduces the main features of the required interactions. The model can be used to study conflicts, political struggles, political parties, social networks, wars and organizational structures. As an application, we analyze a simplified model of the Iraq war.
Three-body approach to the nucleon-nucleus optical potential
International Nuclear Information System (INIS)
Tandy, P.C.; Redish, E.F.; Bolle, D.
1976-01-01
In the Watson single scattering theory of the optical potential it is customary to approximate the propagation by two-body Green functions in order to simplify calculations. The reaction mechanism being described, however, is decidedly three-body in character. The central difficulty in building three-body models for nucleon-nucleus elastic scattering is to find the proper way of imbedding the superposed three-body reaction mechanism in the many-body problem without introducing serious overcounting effects. One would also like an explicit description of the intermediate state processes responsible for absorption. In this paper a three-body approximation to the optical potential theory is presented which overcomes the overcounting problem and is capable of including the following effects: (1) the proper kinematics of the struck nucleon, (2) its binding potential, (3) the identity of target nucleons, and (4) realistic wave functions and spectroscopic factors. The three-body model for the optical potential can be extended using unitarity methods to yield a unified three-body-like model of elastic scattering, pickup, and single nucleon knockout. (Auth.)
Glazier, Samantha; Marano, Nadia; Eisen, Laura
2010-01-01
We describe how we use boiling-point trends of group IV-VII hydrides to introduce intermolecular forces in our first-year general chemistry classes. Starting with the idea that molecules in the liquid state are held together by some kind of force that must be overcome for boiling to take place, students use data analysis and critical reasoning to…
Three-body interactions and the elastic constants of hcp solid 4He
Barnes, Ashleigh L.; Hinde, Robert J.
2017-09-01
The effect of three-body interactions on the elastic properties of hexagonal close packed solid 4He is investigated using variational path integral (VPI) Monte Carlo simulations. The solid's nonzero elastic constants are calculated, at T = 0 K and for a range of molar volumes from 7.88 cm3/mol to 20.78 cm3/mol, from the bulk modulus and the three pure shear constants C0, C66, and C44. Three-body interactions are accounted for using our recently reported perturbative treatment based on the nonadditive three-body potential of Cencek et al. Previous studies have attempted to account for the effect of three-body interactions on the elastic properties of solid 4He; however, these calculations have treated zero point motions using either the Einstein or Debye approximations, which are insufficient in the molar volume range where solid 4He is characterized as a quantum solid. Our VPI calculations allow for a more accurate treatment of the zero point motions which include atomic correlation. From these calculations, we find that agreement with the experimental bulk modulus is significantly improved when three-body interactions are considered. In addition, three-body interactions result in non-negligible differences in the calculated pure shear constants and nonzero elastic constants, particularly at higher densities, where differences of up to 26.5% are observed when three-body interactions are included. We compare to the available experimental data and find that our results are generally in as good or better agreement with experiment as previous theoretical investigations.
2004-01-01
This image composite shows two of the Mars Exploration Rover Opportunity's magnets, the 'capture' magnet (upper portion of left panel) and the 'filter' magnet (lower portion of left panel). Scientists use these tools to study the origins of martian dust in the atmosphere. The left panel was taken by the rover's panoramic camera. The four panels to the right, taken by the microscopic imager, show close-up views of the two magnets. The bull's-eye appearance of the capture magnet is a result of alternating magnetic fields, which are used to increase overall magnetic force. The filter magnet lacks these alternating fields and consequently produces a weaker magnetic force. This weaker force selectively attracts only strong magnetic particles. Scientists were surprised by the large dark particles on the magnets because airborne particles are smaller in size. They theorize that these spots might be aggregates of small particles that clump together in a magnetic field.
A cluster expansion for bound three-alpha particles as a three-body problem
International Nuclear Information System (INIS)
Osman, A.
1981-08-01
A three-body model is proposed to study the nuclear bound states. The nucleus is described as a bound state of three clusters. A cluster expansion is introduced for the three cluster bound state problem. The present integral equations are treated by simple approximate solutions, which lead to effective potentials by using the present cluster expansion. The 12 C nucleus is described as a three-alpha particle bound state. The binding energy of 12 C is calculated numerically using the present cluster expansion as bound three-alpha clusters. The present three-body cluster expansion calculations are very near to the exact three-body calculations using separable potentials. The present theoretical calculations are in good agreement with the experimental measurements. (author)
A comprehensive treatment of electromagnetic interactions and the three-body spectator equations
Energy Technology Data Exchange (ETDEWEB)
Jiri Adam; Jay Van Orden
2004-10-01
We present a general derivation the three-body spectator (Gross) equations and the corresponding electromagnetic currents. As in previous paper on two-body systems, the wave equations and currents are derived from those for Bethe-Salpeter equation with the help of algebraic method using a concise matrix notation. The three-body interactions and currents introduced by the transition to the spectator approach are isolated and the matrix elements of the e.m. current are presented in detail for system of three indistinguishable particles, namely for elastic scattering and for two and three body break-up. The general expressions are reduced to the one-boson-exchange approximation to make contact with previous work. The method is general in that it does not rely on introduction of the electromagnetic interaction with the help of the minimal replacement. It would therefore work also for other external fields.
Tests of the discretized-continuum method in three-body dipole strengths
Energy Technology Data Exchange (ETDEWEB)
Pinilla, E.C., E-mail: epinilla@ulb.ac.be [Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Baye, D., E-mail: dbaye@ulb.ac.be [Physique Quantique, C.P. 165/82, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Descouvemont, P., E-mail: pdesc@ulb.ac.be [Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Horiuchi, W., E-mail: whoriuchi@riken.jp [RIKEN Nishina Center, Wako 351-0918 (Japan); Suzuki, Y., E-mail: suzuki@nt.sc.niigata-u.ac.jp [Department of Physics, Niigata University, Niigata 950-2181 (Japan); RIKEN Nishina Center, Wako 351-0918 (Japan)
2011-08-15
We investigate the {sup 6}He dipole distribution in a three-body {alpha}+n+n model. Two approaches are used to describe the three-body 1{sup -} continuum: the discretized-continuum method, where the scattering wave functions are approximated by square-integrable functions, and the R-matrix formalism, where their asymptotic behaviour is taken into account. We show that some ambiguity exists in the pseudostate method, owing to the smoothing technique, necessary to derive continuous distributions. We show evidence for the important role of the halo structure in the E1 dipole strength. We also address the treatment of Pauli forbidden states in the three-body wave functions.
Contact parameters in two dimensions for general three-body systems
DEFF Research Database (Denmark)
F. Bellotti, F.; Frederico, T.; T. Yamashita, M.
2014-01-01
a subsystem is composed of two identical non-interacting particles. We also show that the three-body contact parameter is negligible in the case of one non-interacting subsystem compared to the situation where all subsystem are bound. As example, we present results for mixtures of Lithium with two Cesium......We study the two dimensional three-body problem in the general case of three distinguishable particles interacting through zero-range potentials. The Faddeev decomposition is used to write the momentum-space wave function. We show that the large-momentum asymptotic spectator function has the same...... to obtain two- and three-body contact parameters. We specialize from the general cases to examples of two identical, interacting or non-interacting, particles. We find that the two-body contact parameter is not a universal constant in the general case and show that the universality is recovered when...
More than six hundred new families of Newtonian periodic planar collisionless three-body orbits
Li, XiaoMing; Liao, ShiJun
2017-12-01
The famous three-body problem can be traced back to Isaac Newton in the 1680s. In the 300 years since this "three-body problem" was first recognized, only three families of periodic solutions had been found, until 2013 when Šuvakov and Dmitrašinović [Phys. Rev. Lett. 110, 114301 (2013)] made a breakthrough to numerically find 13 new distinct periodic orbits, which belong to 11 new families of Newtonian planar three-body problem with equal mass and zero angular momentum. In this paper, we numerically obtain 695 families of Newtonian periodic planar collisionless orbits of three-body system with equal mass and zero angular momentum in case of initial conditions with isosceles collinear configuration, including the well-known figure-eight family found by Moore in 1993, the 11 families found by Šuvakov and Dmitrašinović in 2013, and more than 600 new families that have never been reported, to the best of our knowledge. With the definition of the average period T = T/L f, where L f is the length of the so-called "free group element", these 695 families suggest that there should exist the quasi Kepler's third law T* ≈ 2:433 ± 0:075 for the considered case, where T ≈ = T | E|3/2 is the scale-invariant average period and E is its total kinetic and potential energy, respectively. The movies of these 695 periodic orbits in the real space and the corresponding close curves on the "shape sphere" can be found via the website: http://numericaltank.sjtu.edu.cn/three-body/three-body.htm.
On the inherent self-excited macroscopic randomness of chaotic three-body system
Liao, Shijun; Li, Xiaoming
2014-01-01
What is the origin of macroscopic randomness (uncertainty)? This is one of the most fundamental open questions for human being. In this paper, 10000 samples of reliable (convergent), multiple-scale (from 1.0E-60 to 100) numerical simulations of a chaotic three-body system indicate that, without any external disturbance, the microscopic inherent uncertainty (in the level of 1.0E-60) due to physical fluctuation of initial positions of the three-body system enlarges exponentially into macroscopi...
Stability of the three-body Coulomb systems with J=1 in the oscillator representation
International Nuclear Information System (INIS)
Dinejkhan, M.D.; Efimov, G.V.
1995-01-01
The oscillator representation is applied to calculate the energy spectrum of three-body Coulomb systems with J total angular momentum. For the three-body Coulomb systems with J=1 and arbitrary masses the region of stability is determined. For the systems (A + A - e - ), (pe - C + ), (pB - e - ) and (D + e - e + ), the values for the critical masses of A-, B-, C- and D-particles are obtained: m A =2.22m e , m B =1.49m e , m C =2.11m e and m D =4.15m e . 18 refs., 1 fig., 3 tabs
Using Three-Body Recombination to Extract Electron Temperatures of Ultracold Plasmas
International Nuclear Information System (INIS)
Fletcher, R. S.; Zhang, X. L.; Rolston, S. L.
2007-01-01
Three-body recombination, an important collisional process in plasmas, increases dramatically at low electron temperatures, with an accepted scaling of T e -9/2 . We measure three-body recombination in an ultracold neutral xenon plasma by detecting recombination-created Rydberg atoms using a microwave-ionization technique. With the accepted theory (expected to be applicable for weakly coupled plasmas) and our measured rates, we extract the plasma temperatures, which are in reasonable agreement with previous measurements early in the plasma lifetime. The resulting electron temperatures indicate that the plasma continues to cool to temperatures below 1 K
A new method for calculating the hyperspherical functions for the quantum mechanics of three bodies
International Nuclear Information System (INIS)
Marsh, S.; Buck, B.
1982-01-01
Using the shift operators of Hughes (J. Phys. A.; 6:48 and 281 (1973)) for the group SU(3) in an O(3) basis, a simple method is developed to obtain the three-body hyperspherical functions of a definite symmetry for any angular momentum in a given SU(3) representation. (author)
Effect of three-body transformed Hamiltonian (H3) using full ...
Indian Academy of Sciences (India)
Home; Journals; Pramana – Journal of Physics; Volume 90; Issue 3 ... Research Article Volume 90 Issue 3 March 2018 Article ID 36 ... Valence universal multireference coupled cluster (VUMRCC) method via eigenvalue independent partitioning has been applied to estimate the effect of three-body transformed Hamiltonian ...
Correlation properties of a three-body bosonic mixture in a harmonic trap
DEFF Research Database (Denmark)
Barfknecht, R. E.; Salami Dehkharghani, Amin; Foerster, A.
2016-01-01
We make use of a simple pair correlated wave function approach to obtain results for the ground-state densities and momentum distribution of a one-dimensional three-body bosonic system with different interactions in a harmonic trap. For equal interactions this approach is able to reproduce the kn...
Stripping reactions in a three-body system. Comparison of DWBA and exact solutions
International Nuclear Information System (INIS)
Brinati, J.R.
1976-01-01
Stripping reactions 'a estados no continuo' are studied in a three particle system. Since the three-body problem has an exact treatment, comparison will be made between the exact solution and the DWBA model solution. This problem is more complex in the continuous case, as shown in the convergence problem of the standard DWBA amplitude radial integral
Efimov three-body states on top of a Fermi sea
DEFF Research Database (Denmark)
Nygaard, Nicolai Gayle; Zinner, Nikolaj Thomas
2014-01-01
The stabilization of Cooper pairs of bound electrons in the background of a Fermi sea is the origin of superconductivity and the paradigmatic example of the striking influence of many-body physics on few-body properties. In the quantum-mechanical three-body problem the famous Efimov effect yields...
Virtual states, halos and resonances in three-body atomic and nuclear systems
International Nuclear Information System (INIS)
Frederico, T.; Yamashita, M.T.; Tomio, L.
2009-01-01
By considering nuclear and ultracold trapped atomic systems, we review the trajectory of Efimov excited states in the complex plane by changing the two-body scattering lengths and one three-body scale. This article is based on the presentation by T. Frederico at the Fifth Workshop on Critical Stability, Erice, Sicily. (author)
Low-lying spectra in anharmonic three-body oscillators with a strong short-range
Czech Academy of Sciences Publication Activity Database
Znojil, Miloslav
2003-01-01
Roč. 36, č. 38 (2003), s. 9929-9941 ISSN 0305-4470 R&D Projects: GA AV ČR IAA1048302 Institutional research plan: CEZ:AV0Z1048901 Keywords : three-body Schrodinger equation * limit * large repulsion Subject RIV: BE - Theoretical Physics Impact factor: 1.357, year: 2003
Investigation of halo structure of He by hyperspherical three-body ...
Indian Academy of Sciences (India)
Abstract. Hyperspherical harmonics expansion method is applied to a three-body model of two neutron halo nuclei. Convergence of the expansion has been ensured. A repulsive part is introduced in the interaction between the core and the extra-core neutron, to simulate Pauli principle. Two neutron separation energy ...
Efimov trimers in a harmonic potential and universality in three-body recombination
Kokkelmans, S.J.J.M.F.; Portegies, J.W.; Gross, N.; Shotan, Z.; Khaykovich, L.
2009-01-01
We report on experimental evidence of universality in ultracold 7Li atoms’three-body recombination loss in the vicinity of a Feshbach resonance [1]. We observe a recombination minimum and an Efimov resonance in regions of positive and negative scattering lengths. Both observed features lie deeply
International Nuclear Information System (INIS)
Zaytsev, S A
2010-01-01
The possibility of using straight-line paths of integration in computing the integral representation of the three-body Coulomb Green's function is discussed. In our numerical examples two different kinds of integration contours in the complex energy planes are considered. It is demonstrated that straight-line paths, which cross the positive real axis, are suitable for numerical computation.
Three-body interactions in many-body effective field theory
International Nuclear Information System (INIS)
Furnstahl, R.J.
2004-01-01
This contribution is an advertisement for applying effective field theory (EFT) to many-body problems, including nuclei and cold atomic gases. Examples involving three-body interactions are used to illustrate how EFT's quantify and systematically eliminate model dependence, and how they make many-body calculations simpler and more powerful
Leigh, Nathan W. C.; Wegsman, Shalma
2018-05-01
We present a formalism for constructing schematic diagrams to depict chaotic three-body interactions in Newtonian gravity. This is done by decomposing each interaction into a series of discrete transformations in energy- and angular momentum-space. Each time a transformation is applied, the system changes state as the particles re-distribute their energy and angular momenta. These diagrams have the virtue of containing all of the quantitative information needed to fully characterize most bound or unbound interactions through time and space, including the total duration of the interaction, the initial and final stable states in addition to every intervening temporary meta-stable state. As shown via an illustrative example for the bound case, prolonged excursions of one of the particles, which by far dominates the computational cost of the simulations, are reduced to a single discrete transformation in energy- and angular momentum-space, thereby potentially mitigating any computational expense. We further generalize our formalism to sequences of (unbound) three-body interactions, as occur in dense stellar environments during binary hardening. Finally, we provide a method for dynamically evolving entire populations of binaries via three-body scattering interactions, using a purely analytic formalism. In principle, the techniques presented here are adaptable to other three-body problems that conserve energy and angular momentum.
LAGRANGE SOLUTIONS TO THE DISCRETE-TIME GENERAL THREE-BODY PROBLEM
International Nuclear Information System (INIS)
Minesaki, Yukitaka
2013-01-01
There is no known integrator that yields exact orbits for the general three-body problem (G3BP). It is difficult to verify whether a numerical procedure yields the correct solutions to the G3BP because doing so requires knowledge of all 11 conserved quantities, whereas only six are known. Without tracking all of the conserved quantities, it is possible to show that the discrete general three-body problem (d-G3BP) yields the correct orbits corresponding to Lagrange solutions of the G3BP. We show that the d-G3BP yields the correct solutions to the G3BP for two special cases: the equilateral triangle and collinear configurations. For the triangular solution, we use the fact that the solution to the three-body case is a superposition of the solutions to the three two-body cases, and we show that the three bodies maintain the same relative distances at all times. To obtain the collinear solution, we assume a specific permutation of the three bodies arranged along a straight rotating line, and we show that the d-G3BP maintains the same distance ratio between two bodies as in the G3BP. Proving that the d-G3BP solutions for these cases are equivalent to those of the G3BP makes it likely that the d-G3BP and G3BP solutions are equivalent in other cases. To our knowledge, this is the first work that proves the equivalence of the discrete solutions and the Lagrange orbits.
Tensor force and delta excitation for the structure of light nuclei
International Nuclear Information System (INIS)
Horii, K; Myo, T; Toki, H
2014-01-01
We treat explicitly Δ(1232) isobar degrees of freedom using a bare nucleon-nucleon interaction for few-body systems, where Δ excitations can be the origin of the three-body force via the pion exchange. We adopt the Argonne two-body potential including Δ, named as AV28 potential, and study the role of Δ explicitly in two-body and three-body systems. It was found that the additional Δ states generate strong tensor correlations caused by the transitions between N and Δ states, and change tensor matrix elements largely from the results with only nucleons. We studied the effects of three-body force in the triton and obtained 0.8 MeV attraction due to the intermediate Δ excitation. Due to the lack of the total binding energy for the triton in the delta model, we further studied carefully the effects of the delta excitation in various two body channels and compared with the nucleon only model in the AV14 potential. We modified slightly the AV28 potential in the singlet S channel so that we could reproduce the triton binding energy due to the appropriate amount of the three-body force effects
Three-body problem in quantum mechanics: Hyperspherical elliptic coordinates and harmonic basis sets
International Nuclear Information System (INIS)
Aquilanti, Vincenzo; Tonzani, Stefano
2004-01-01
Elliptic coordinates within the hyperspherical formalism for three-body problems were proposed some time ago [V. Aquilanti, S. Cavalli, and G. Grossi, J. Chem. Phys. 85, 1362 (1986)] and recently have also found application, for example, in chemical reaction theory [see O. I. Tolstikhin and H. Nakamura, J. Chem. Phys. 108, 8899 (1998)]. Here we consider their role in providing a smooth transition between the known 'symmetric' and 'asymmetric' parametrizations, and focus on the corresponding hyperspherical harmonics. These harmonics, which will be called hyperspherical elliptic, involve products of two associated Lame polynomials. We will provide an expansion of these new sets in a finite series of standard hyperspherical harmonics, producing a powerful tool for future applications in the field of scattering and bound-state quantum-mechanical three-body problems
Realizing all reduced syzygy sequences in the planar three-body problem
International Nuclear Information System (INIS)
Moeckel, Richard; Montgomery, Richard
2015-01-01
The configuration space of the planar three-body problem, reduced by rotations and with collisions excluded, has a rich topology which supports a large set of free homotopy classes. These classes have a simple description in terms of syzygy (or eclipse) sequences. Each homotopy class corresponds to a unique ‘reduced’ syzygy sequence. We prove that each reduced syzygy sequence is realized by a periodic solution of the rotation-reduced Newtonian planar three-body problem. The realizing solutions have small, nonzero angular momentum, repeatedly come very close to triple collision, and have lots of ‘stutters’—repeated syzygies of the same type, which cancel out up to homotopy. The heart of the proof stems from the work by one of us on symbolic dynamics arising out of the central configurations after the triple collision is blown up using McGehee's method. We end with a list of open problems. (paper)
Non-integrability of the Anisotropic Stormer Problem and the Isosceles Three-Body Problem
Nomikos, D. G.; Papageorgiou, V. G.
2009-02-01
We study the Anisotropic Stormer Problem (ASP) and the Isosceles Three-Body Problem (IP), from the viewpoint of integrability, using Morales-Ramis theory and its generalization. The study of their integrability presents particular interest since they model important physical phenomena. Both problems can be reduced with respect to the S1 symmetry. Almeida and Stuchi [M.A. Almeida, T.J. Stuchi, Non-integrability of the anisotropic Stormer problem with angular momentum, Physica D 189 (2004) 219-233] proved that the reduced ASP is non-integrable for almost all values of the parameters. In this paper we establish the non-integrability (in the extended Liouville sense) of the remaining cases. The IP is a special case of the three-body problem and it can be considered as a generalization of the Sitnikov problem. Here we prove that the complexified reduced IP does not admit an additional independent meromorphic first integral.
Efimov three-body states on top of a Fermi sea
International Nuclear Information System (INIS)
Nygaard, Nicolai Gayle; Zinner, Nikolaj Thomas
2014-01-01
The stabilization of Cooper pairs of bound electrons in the background of a Fermi sea is the origin of superconductivity and the paradigmatic example of the striking influence of many-body physics on few-body properties. In the quantum-mechanical three-body problem the famous Efimov effect yields unexpected scaling relations among a tower of universal states. These seemingly unrelated problems can now be studied in the same setup thanks to the success of ultracold atomic gas experiments. In light of the tremendous effect of a background Fermi sea on two-body properties, a natural question is whether a background can modify or even destroy the Efimov effect. Here we demonstrate how the generic problem of three interacting particles changes when one particle is embedded in a background Fermi sea, and show that Efimov scaling persists. It is found in a scaling that relates the three-body physics to the background density of fermionic particles
Lagrangian relative equilibria for a gyrostat in the three-body problem: bifurcations and stability
Energy Technology Data Exchange (ETDEWEB)
Guirao, Juan L G; Vera, Juan A, E-mail: juan.garcia@upct.e, E-mail: juanantonio.vera@upct.e [Departamento de Matematica Aplicada y EstadIstica, Universidad Politecnica de Cartagena, Hospital de Marina, 30203 Cartagena, Region de Murcia (Spain)
2010-05-14
In this paper we consider the non-canonical Hamiltonian dynamics of a gyrostat in the frame of the three-body problem. Using geometric/mechanic methods we study the approximate dynamics of the truncated Legendre series representation of the potential of an arbitrary order. Working in the reduced problem, we study the existence of relative equilibria that we refer to as Lagrange type following the analogy with the standard techniques. We provide necessary and sufficient conditions for the linear stability of Lagrangian relative equilibria if the gyrostat morphology form is close to a sphere. Thus, we generalize the classical results on equilibria of the three-body problem and many results on them obtained by the classic approach for the case of rigid bodies.
The motion and control of a complex three-body space tethered system
Shi, Gefei; Zhu, Zhanxia; Chen, Shiyu; Yuan, Jianping; Tang, Biwei
2017-11-01
This paper is mainly devoted to investigating the dynamics and stability control of a three body-tethered satellite system which contains a main satellite and two subsatellites connected by two straight, massless and inextensible tethers. Firstly, a detailed mathematical model is established in the central gravitational field. Then, the dynamic characteristics of the established system are investigated and analyzed. Based on the dynamic analysis, a novel sliding mode prediction model (SMPM) control strategy is proposed to suppress the motion of the built tethered system. The numerical results show that the proposed underactuated control law is highly effective in suppressing the attitude/libration motion of the underactuated three-body tethered system. Furthermore, cases of different target angles are also examined and analyzed. The simulation results reveal that even if the final equilibrium states differ from different selections of the target angles, the whole system can still be maintained in acceptable areas.
Incorporation of threshold phenomena in the three-body Coulomb continuum wavefunctions
International Nuclear Information System (INIS)
Berakdar, J.
1996-01-01
In this work a three-body Coulomb wavefunction for the description of two continuum electrons moving in the field of a nucleus is constructed such that the Wannier threshold law for double escape is reproduced and the asymptotic Coulomb boundary conditions as well as the Kato cusp conditions are satisfied. It is shown that the absolute value of the total cross section, as well as the spin asymmetry, are well described by the present approach. Further, the excess-energy sharing between the two escaping electrons is calculated and analysed in light of the Wannier theory predictions. This is the first time an analytical three-body wavefunction is presented which is asymptotically exact and capable of describing threshold phenomena. 37 refs., 3 figs
A method for solving a three-body problem with energy-dependent interactions
International Nuclear Information System (INIS)
Safronov, A.N.
1994-01-01
A method is proposed for solving a three-body problem with energy-dependent interactions. This method is based on introducing the dependence of scattering operators and state vectors on an additional external parameter. Effects caused by the energy dependence of the interaction operator are investigated by using the unitary condition for the amplitude of the 2 → 2 and 2 → 3 transitions. It is shown, in particular, that taking this dependence into account leads to a change in the relation between the asymptotic normalization factor of the wave function of the three-body bound state and the vertex constant of virtual dissociation (synthesis) of the system into two fragments. 15 refs
The annihilation diagram in three-body D-meson decay
International Nuclear Information System (INIS)
Donoghue, J.F.; Holstein, B.R.
1981-01-01
We discuss some features of three-body decays of the D meson cohich are puzzling from the standpoint of the annihilation diagram. As a result, we (1) provide an upper bound on the lifetime ratio of D's, tau + sub(D)/tau 0 sub(D) smaller than 2.5 +- 3.4 and (2) argue that the puzzles are resolved, even if somewhat inelegantly, if final state interactions generate the annihilation diagram. (orig.)
Relativistic three-body model of pion-deuton elasic scattering
International Nuclear Information System (INIS)
Giraud, Noel.
1978-01-01
The Aaron-Amado-Young equations for the relativistic three-body problem are derived following the Blauckenbecker - Sugar method. The angular momentum reduction is carried out using suitable relative momenta. The pion-deuteron elastic scattering is calculated using the equations in which relativistic kinematics are retained only for the pion. After a general study of the observables in the energy range 25 to 256 MeV, detailed calculations are performed at 142 MeV [fr
Asymptotic form of three-body (dtμ)+ and (ddμ)+ wave functions
International Nuclear Information System (INIS)
Kino, Y.; Shimamura, I.; Armour, E.A.G.; Kamimura, M.
1996-01-01
In order to investigate a discrepancy between existing literature values for the normalization constant in the asymptotic form of three-body wave functions for (DTμ) + , we report the results of a new calculation of the normalization constants for this system as well as the related system (DDμ) + . These were obtained by fitting to accurate variational wave functions with special care being taken to describe the long-range behavior. (orig.)
Application of Symplectic Algebraic Dynamics Algorithm to Circular Restricted Three-Body Problem
International Nuclear Information System (INIS)
Wei-Tao, Lu; Hua, Zhang; Shun-Jin, Wang
2008-01-01
Symplectic algebraic dynamics algorithm (SADA) for ordinary differential equations is applied to solve numerically the circular restricted three-body problem (CR3BP) in dynamical astronomy for both stable motion and chaotic motion. The result is compared with those of Runge–Kutta algorithm and symplectic algorithm under the fourth order, which shows that SADA has higher accuracy than the others in the long-term calculations of the CR3BP. (general)
Lu, Wei-Tao; Zhang, Hua; Wang, Shun-Jin
2008-07-01
Symplectic algebraic dynamics algorithm (SADA) for ordinary differential equations is applied to solve numerically the circular restricted three-body problem (CR3BP) in dynamical astronomy for both stable motion and chaotic motion. The result is compared with those of Runge-Kutta algorithm and symplectic algorithm under the fourth order, which shows that SADA has higher accuracy than the others in the long-term calculations of the CR3BP.
Three-body fragmentation of methane dications produced by slow A r8 + -ion impact
Zhang, Y.; Jiang, T.; Wei, L.; Luo, D.; Wang, X.; Yu, W.; Hutton, R.; Zou, Y.; Wei, B.
2018-02-01
The three-body fragmentation dynamics of CH4 2 + dications induced by single-electron capture of slow (3-keV/u) A r8 + ions is investigated. The experiment is performed on a newly built, highly charged ion collision platform which consists of an electron cyclotron resonance ion source and a cold target recoil ion momentum spectroscopy (COLTRIMS) setup. Using the COLTRIMS methodology, the complete kinematical information is determined for two three-body breakup channels, CH4 2 +→H++CH2 ++H and CH4 2 +→H2 ++C H++H . Then analyzing the complete kinematics with the Dalitz plot, very different fragmentation mechanisms (e.g., sequential and/or concerted pathway) are clearly identified for the two channels. To confirm the existence of some possible fragmentation pathways, we also simulate corresponding Dalitz plots employing a simple classical mechanical model. For the H++CH2 ++H channel, the dependence of the fragmentation pathway on its kinetic energy release is studied, which reflects the different nature of the corresponding states of CH4 2 + dications. Furthermore, the kinetic energy ratio of two ionic fragments is analyzed to infer the three-body fragmentation mechanism of CH4 2 + dications.
RESONANT POST-NEWTONIAN ECCENTRICITY EXCITATION IN HIERARCHICAL THREE-BODY SYSTEMS
Energy Technology Data Exchange (ETDEWEB)
Naoz, Smadar; Kocsis, Bence; Loeb, Abraham [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Yunes, Nicolas, E-mail: snaoz@cfa.harvard.edu [Department of Physics, Montana State University, Bozeman, MT 59718 (United States)
2013-08-20
We study the secular, hierarchical three-body problem to first-order in a post-Newtonian expansion of general relativity (GR). We expand the first-order post-Newtonian Hamiltonian to leading-order in the ratio of the semi-major axis of the two orbits. In addition to the well-known terms that correspond to the GR precession of the inner and outer orbits, we find a new secular post-Newtonian interaction term that can affect the long-term evolution of the triple. We explore the parameter space for highly inclined and eccentric systems, where the Kozai-Lidov mechanism can produce large-amplitude oscillations in the eccentricities. The standard lore, i.e., that GR effects suppress eccentricity, is only consistent with the parts of phase space where the GR timescales are several orders of magnitude shorter than the secular Newtonian one. In other parts of phase space, however, post-Newtonian corrections combined with the three-body ones can excite eccentricities. In particular, for systems where the GR timescale is comparable to the secular Newtonian timescales, the three-body interactions give rise to a resonant-like eccentricity excitation. Furthermore, for triples with a comparable-mass inner binary, where the eccentric Kozai-Lidov mechanism is suppressed, post-Newtonian corrections can further increase the eccentricity and lead to orbital flips even when the timescale of the former is much longer than the timescale of the secular Kozai-Lidov quadrupole perturbations.
Two-body and three-body correlations in Os-shell nuclei
International Nuclear Information System (INIS)
Halderson, D.W.
1974-01-01
It is well known that conventional Brueckner calculations with modern nucleon-nucleon potentials have failed to reproduce experimental saturation properties of finite nuclei. The intent was to determine whether the discrepancies are due to the methods of calculation or the nucleon-nucleon potentials. Brueckner procedures which include only two-body correlations were applied to Os-shell nuclei. Calculations were performed with and without the Hartree-Fock condition, with and without partial occupation probabilities, and with various propagators and Pauli correction techniques. Then the entire class of three-body correlations was calculated by matrix solution of the Bethe-Faddeev equations. The convergence necessary to validate this technique was achieved by constructing a set of basic functions which contain no center of mass excitations and yet are still properly antisymmetrized. The two-body calculations yielded typical Brueckner results. The nuclei were underbound or the radii were too small. However, the three-body calculations yielded reasonable radii and moderate overbinding for the Reid soft core and Hamada-Johnston potentials. Therefore, the Bethe-Faddeev formalism has been shown to be a reasonable approach to calculation of the three-body correlations in finite nuclei; and the results of []these calculations demonstrate that the underbinding and collapsed radii of two-body calculations were largely due to the uncalculated correlations. (auth)
Lyapunov vs. geometrical stability analysis of the Kepler and the restricted three body problems
International Nuclear Information System (INIS)
Yahalom, A.; Levitan, J.; Lewkowicz, M.; Horwitz, L.
2011-01-01
In this Letter we show that although the application of standard Lyapunov analysis predicts that completely integrable Kepler motion is unstable, the geometrical analysis of Horwitz et al. predicts the observed stability. This seems to us to provide evidence for both the incompleteness of the standard Lyapunov analysis and the strength of the geometrical analysis. Moreover, we apply this approach to the three body problem in which the third body is restricted to move on a circle of large radius which induces an adiabatic time dependent potential on the second body. This causes the second body to move in a very interesting and intricate but periodic trajectory; however, the standard Lyapunov analysis, as well as methods based on the parametric variation of curvature associated with the Jacobi metric, incorrectly predict chaotic behavior. The geometric approach predicts the correct stable motion in this case as well. - Highlights: → Lyapunov analysis predicts Kepler motion to be unstable. → Geometrical analysis predicts the observed stability. → Lyapunov analysis predicts chaotic behavior in restricted three body problem. → The geometric approach predicts the correct stable motion in restricted three body problem.
Stability and periodicity in the Sitnikov three-body problem when primaries are oblate spheroids
Rahman, M. A.; Garain, D. N.; Hassan, M. R.
2015-05-01
This paper deals with the effect of oblateness of the primaries of equal masses on the series solutions of the Sitnikov problem of three bodies. Effects of oblateness have also been shown on the stability of libration points and Poincare surface of section. Here series solutions have been developed with the help of iteration process of Green's function and by the Lindstedt-Poincare method. Following Murray and Dermott (Solar System Dynamics, Cambridge University Press, Cambridge, 1999) we have checked the stability of the equilibrium points in the Sitnikov problem. Periodicity and quasi-periodicity have been examined by drawing the Poincare surfaces of section using the mathematical software.
On the motion of classical three-body system with consideration of quantum fluctuations
Energy Technology Data Exchange (ETDEWEB)
Gevorkyan, A. S., E-mail: g-ashot@sci.am [NAS of RA, Institute for Informatics and Automation Problems (Armenia)
2017-03-15
We obtained the systemof stochastic differential equations which describes the classicalmotion of the three-body system under influence of quantum fluctuations. Using SDEs, for the joint probability distribution of the total momentum of bodies system were obtained the partial differential equation of the second order. It is shown, that the equation for the probability distribution is solved jointly by classical equations, which in turn are responsible for the topological peculiarities of tubes of quantum currents, transitions between asymptotic channels and, respectively for arising of quantum chaos.
Correlation properties of a three-body bosonic mixture in a harmonic trap
International Nuclear Information System (INIS)
Barfknecht, R E; Foerster, A; Dehkharghani, A S; Zinner, N T
2016-01-01
We make use of a simple pair correlated wave function approach to obtain results for the ground-state densities and momentum distribution of a one-dimensional three-body bosonic system with different interactions in a harmonic trap. For equal interactions this approach is able to reproduce the known analytical cases of zero and infinite repulsion. We show that our results for the correlations agree with the exact diagonalization in all interaction regimes and with analytical results for the strongly repulsive impurity. This method also enables us to access the more complicated cases of mixed interactions, and the probability densities of these systems are analyzed. (paper)
Explicit solution of the quantum three-body Calogero-Sutherland model
Perelomov, A.M.; Zaugg, P.
1998-01-01
Quantum integrable systems generalizing Calogero-Sutherland systems were introduced by Olshanetsky and Perelomov (1977). Recently, it was proved that for systems with trigonometric potential, the series in the product of two wave functions is a deformation of the Clebsch-Gordan series. This yields recursion relations for the wave functions of those systems. In this note, this approach is used to compute the explicit expressions for the three-body Calogero-Sutherland wave functions, which are the Jack polynomials. We conjecture that similar results are also valid for the more general two-parameters deformation introduced by Macdonald.
Continuous atom laser with Bose-Einstein condensates involving three-body interactions
Energy Technology Data Exchange (ETDEWEB)
Carpentier, A V; Michinel, H; Novoa, D [Area de Optica, Facultade de Ciencias de Ourense, Universidade de Vigo, As Lagoas s/n, Ourense, ES-32004 (Spain); Olivieri, D N, E-mail: avcarpentier@uvigo.e [Area de Linguaxes e sistemas informaticos, Escola Superior de EnxenerIa Informatica, Universidade de Vigo, As Lagoas s/n, Ourense, ES-32004 (Spain)
2010-05-28
We demonstrate, through numerical simulations, the emission of a coherent continuous matter wave of constant amplitude from a Bose-Einstein condensate in a shallow optical dipole trap. The process is achieved by spatial control of the variations of the scattering length along the trapping axis, including elastic three-body interactions due to dipole interactions. In our approach, the outcoupling mechanism is atomic interactions, and thus, the trap remains unaltered. We calculate analytically the parameters for the experimental implementation of this continuous wave atom laser.
Attractive evolutionary equilibria
Roorda, Berend; Joosten, Reinoud
2011-01-01
We present attractiveness, a refinement criterion for evolutionary equilibria. Equilibria surviving this criterion are robust to small perturbations of the underlying payoff system or the dynamics at hand. Furthermore, certain attractive equilibria are equivalent to others for certain evolutionary dynamics. For instance, each attractive evolutionarily stable strategy is an attractive evolutionarily stable equilibrium for certain barycentric ray-projection dynamics, and vice versa.
Attracting electromagnet for control rod
International Nuclear Information System (INIS)
Kato, Kazuo; Sasaki, Kotaro.
1989-01-01
Non-magnetic material plates with inherent resistivity of greater than 20 μΩ-cm and thickness of less than 3 mm are used for the end plates of attracting electromagnets for closed type control rods. By using such control rod attracting electromagnets, the scram releasing time can be shortened than usual. Since the armature attracting side of the electromagnet has to be sealed by a non-magnetic plate, a bronze plate of about 5 mm thickness has been used so far. Accordingly, non-magnetic plate is inserted to the electromagnet attracting face to increase air source length for improving to shorten the scram releasing time. This method, however, worsens the attracting property on one hand to require a great magnetomotive force. For overcoming these drawbacks, in the present invention, the material for tightly closing end plates in an electromagnet is changed from bronze plate to non-magnetic stainless steel SUS 303 or non-magnetic Monel metal and, in addition, the plate thickness is reduced to less than 5 mm thereby maintaining the attracting property and shortening the scram releasing time. (K.M.)
Rheology of attractive emulsions.
Datta, Sujit S; Gerrard, Dustin D; Rhodes, Travers S; Mason, Thomas G; Weitz, David A
2011-10-01
We show how attractive interactions dramatically influence emulsion rheology. Unlike the repulsive case, attractive emulsions below random close packing, φ(RCP), can form soft gel-like elastic solids. However, above φ(RCP), attractive and repulsive emulsions have similar elasticities. Such compressed attractive emulsions undergo an additional shear-driven relaxation process during yielding. Our results suggest that attractive emulsions begin to yield at weak points through the breakage of bonds, and, above φ(RCP), also undergo droplet configurational rearrangements.
Hyperspherical Coulomb spheroidal basis in the Coulomb three-body problem
International Nuclear Information System (INIS)
Abramov, D. I.
2013-01-01
A hyperspherical Coulomb spheroidal (HSCS) representation is proposed for the Coulomb three-body problem. This is a new expansion in the set of well-known Coulomb spheroidal functions. The orthogonality of Coulomb spheroidal functions on a constant-hyperradius surface ρ = const rather than on a constant-internuclear-distance surface R = const, as in the traditional Born-Oppenheimer approach, is a distinguishing feature of the proposed approach. Owing to this, the HSCS representation proves to be consistent with the asymptotic conditions for the scattering problem at energies below the threshold for three-body breakup: only a finite number of radial functions do not vanish in the limit of ρ→∞, with the result that the formulation of the scattering problem becomes substantially simpler. In the proposed approach, the HSCS basis functions are considerably simpler than those in the well-known adiabatic hyperspherical representation, which is also consistent with the asymptotic conditions. Specifically, the HSCS basis functions are completely factorized. Therefore, there arise no problems associated with avoided crossings of adiabatic hyperspherical terms.
Emerging bosons with three-body interactions from spin-1 atoms in optical lattices
International Nuclear Information System (INIS)
Mazza, L.; Rizzi, M.; Cirac, J. I.; Lewenstein, M.
2010-01-01
We study two many-body systems of bosons interacting via an infinite three-body contact repulsion in a lattice: a pairs quasicondensate induced by correlated hopping and the discrete version of the Pfaffian wave function. We propose to experimentally realize systems characterized by such interaction by means of a proper spin-1 lattice Hamiltonian: spin degrees of freedom are locally mapped into occupation numbers of emerging bosons, in a fashion similar to spin-1/2 and hardcore bosons. Such a system can be realized with ultracold spin-1 atoms in a Mott insulator with a filling factor of 1. The high versatility of these setups allows us to engineer spin-hopping operators breaking the SU(2) symmetry, as needed to approximate interesting bosonic Hamiltonians with three-body hardcore constraint. For this purpose we combine bichromatic spin-independent superlattices and Raman transitions to induce a different hopping rate for each spin orientation. Finally, we illustrate how our setup could be used to experimentally realize the first setup, that is, the transition to a pairs quasicondensed phase of the emerging bosons. We also report on a route toward the realization of a discrete bosonic Pfaffian wave function and list some open problems for reaching this goal.
3He(d,p)4He reaction calculation with three-body Faddeev equations
International Nuclear Information System (INIS)
Oryu, S.; Uzu, E.; Sunahara, H.; Yamada, T.; Tabaru, G.; Hino, T.
1998-01-01
In order to investigate the 3 He-n-p system as a three-body problem, we have formulated 3 He-n and 3 H-p effective potentials using both a microscopic treatment and a phenomenological approach. In the microscopic treatment, potentials are generated by means of the resonating group method (RGM) based on the Minnesota nucleon-nucleon potential. These potentials are converted into separable form by means of the microscopic Pauli correct (MPC) method. The MPC potentials are properly formulated to avoid Pauli forbidden states. The phenomenological potentials are obtained by modifying parameters of the EST approximation to the Paris nucleon-nucleon potential, such that they fit the low-energy 3 He-n, 3 H-p, and 3 He-p phase shifts. Therefore, they describe the 3 He-n differential cross section, the polarization observables, and the energy levels of 4 He. The 3 He-n-p Faddeev equations are solved numerically. We reproduce correctly the ground state and the first excited state of 5 Li. Furthermore, the Paris-type potential is used to investigate the 3 He(d,p) 4 He reaction at a deuteron bombarding energy of 270 MeV, where the system is treated as a three-body problem. Results for the polarized and unpolarized differential cross sections demonstrate convergence of the Born series. (orig.)
Exact Analytical Solutions in Three-Body Problems and Model of Neutrino Generator
Directory of Open Access Journals (Sweden)
Takibayev N.Zh.
2010-04-01
Full Text Available Exact analytic solutions are obtained in three-body problem for the scattering of light particle on the subsystem of two ﬁxed centers in the case when pair potentials have a separable form. Solutions show an appearance of new resonance states and dependence of resonance energy and width on distance between two ﬁxed centers. The approach of exact analytical solutions is expanded to the cases when two-body scattering amplitudes have the Breit-Wigner’s form and employed for description of neutron resonance scattering on subsystem of two heavy nuclei ﬁxed in nodes of crystalline lattice. It is shown that some resonance states have widths close to zero at the certain values of distance between two heavy scatterer centers, this gives the possibility of transitions between states. One of these transitions between three-body resonance states could be connected with process of electron capture by proton with formation of neutron and emission of neutrino. This exoenergic process leading to the cooling of star without nuclear reactions is discussed.
Coulomb Fourier transformation: A novel approach to three-body scattering with charged particles
International Nuclear Information System (INIS)
Alt, E.O.; Levin, S.B.; Yakovlev, S.L.
2004-01-01
A unitary transformation of the three-body Hamiltonian which describes a system of two charged and one neutral particles is constructed such that the Coulomb potential which acts between the charged particles is explicitly eliminated. The transformed Hamiltonian and, in particular, the transformed short-range pair interactions are worked out in detail. Thereby it is found that, after transformation, the short-range potentials acting between the neutral and either one of the charged particles become simply Fourier transformed but, in addition, multiplied by a function that represents the Coulombic three-body correlations originating from the action of the other charged particle on the considered pair. This function which is universal as it does not depend on any property of the short-range interaction is evaluated explicitly and its singularity structure is described in detail. In contrast, the short-range potential between the charged particles remains of two-body type but occurs now in the 'Coulomb representation'. Specific applications to Yukawa and Gaussian potentials are given. Since the Coulomb-Fourier-transformed Hamiltonian does no longer contain the Coulomb potential or any other effective interaction of long range, standard methods of short-range few-body scattering theory are applicable
Observation of attraction between dark solitons
DEFF Research Database (Denmark)
Dreischuh, A.; Neshev, D.N.; Petersen, D.E.
2006-01-01
We demonstrate a dramatic change in the interaction forces between dark solitons in nonlocal nonlinear media. We present what we believe is the first experimental evidence of attraction of dark solitons. Our results indicate that attraction should be observable in other nonlocal systems...
Myeloperoxidase attracts neutrophils by physical forces
Czech Academy of Sciences Publication Activity Database
Klinke, A.; Nussbaum, C.; Kubala, Lukáš; Friedrichs, K.; Rudolph, T.K.; Rudolph, V.; Paust, H.-J.; Schröder, Ch.; Benten, D.; Lau, D.; Szocs, K.; Furtmüller, P.G.; Heeringa, P.; Sydow, K.; Duchstein, H.-J.; Ehmke, H.; Schumacher, U.; Meinertz, T.; Sperandio, M.; Baldus, S.
2011-01-01
Roč. 117, č. 4 (2011), s. 1350-1358 ISSN 0006-4971 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : myeloperoxidase * polymorphonuclear neutrophils * glycocalyx Subject RIV: BO - Biophysics Impact factor: 9.898, year: 2011
Effects of Instructor Attractiveness on Learning.
Westfall, Richard; Millar, Murray; Walsh, Mandy
2016-01-01
Although a considerable body of research has examined the impact of student attractiveness on instructors, little attention has been given to the influence of instructor attractiveness on students. This study tested the hypothesis that persons would perform significantly better on a learning task when they perceived their instructor to be high in physical attractiveness. To test the hypothesis, participants listened to an audio lecture while viewing a photograph of instructor. The photograph depicted either a physically attractive instructor or a less attractive instructor. Following the lecture, participants completed a forced choice recognition task covering material from the lecture. Consistent with the predictions; attractive instructors were associated with more learning. Finally, we replicated previous findings demonstrating the role attractiveness plays in person perception.
Effect of three-body interactions on the zero-temperature equation of state of HCP solid 4He
Barnes, Ashleigh L.; Hinde, Robert J.
2017-03-01
Previous studies have pointed to the importance of three-body interactions in high density 4He solids. However the computational cost often makes it unfeasible to incorporate these interactions into the simulation of large systems. We report the implementation and evaluation of a computationally efficient perturbative treatment of three-body interactions in hexagonal close packed solid 4He utilizing the recently developed nonadditive three-body potential of Cencek et al. This study represents the first application of the Cencek three-body potential to condensed phase 4He systems. Ground state energies from quantum Monte Carlo simulations, with either fully incorporated or perturbatively treated three-body interactions, are calculated in systems with molar volumes ranging from 21.3 cm3/mol down to 2.5 cm3/mol. These energies are used to derive the zero-temperature equation of state for comparison against existing experimental and theoretical data. The equations of state derived from both perturbative and fully incorporated three-body interactions are found to be in very good agreement with one another, and reproduce the experimental pressure-volume data with significantly better accuracy than is obtained when only two-body interactions are considered. At molar volumes below approximately 4.0 cm3/mol, neither two-body nor three-body equations of state are able to accurately reproduce the experimental pressure-volume data, suggesting that below this molar volume four-body and higher many-body interactions are becoming important.
Three-body problem in d-dimensional space: Ground state, (quasi)-exact-solvability
Turbiner, Alexander V.; Miller, Willard; Escobar-Ruiz, M. A.
2018-02-01
As a straightforward generalization and extension of our previous paper [A. V. Turbiner et al., "Three-body problem in 3D space: Ground state, (quasi)-exact-solvability," J. Phys. A: Math. Theor. 50, 215201 (2017)], we study the aspects of the quantum and classical dynamics of a 3-body system with equal masses, each body with d degrees of freedom, with interaction depending only on mutual (relative) distances. The study is restricted to solutions in the space of relative motion which are functions of mutual (relative) distances only. It is shown that the ground state (and some other states) in the quantum case and the planar trajectories (which are in the interaction plane) in the classical case are of this type. The quantum (and classical) Hamiltonian for which these states are eigenfunctions is derived. It corresponds to a three-dimensional quantum particle moving in a curved space with special d-dimension-independent metric in a certain d-dependent singular potential, while at d = 1, it elegantly degenerates to a two-dimensional particle moving in flat space. It admits a description in terms of pure geometrical characteristics of the interaction triangle which is defined by the three relative distances. The kinetic energy of the system is d-independent; it has a hidden sl(4, R) Lie (Poisson) algebra structure, alternatively, the hidden algebra h(3) typical for the H3 Calogero model as in the d = 3 case. We find an exactly solvable three-body S3-permutationally invariant, generalized harmonic oscillator-type potential as well as a quasi-exactly solvable three-body sextic polynomial type potential with singular terms. For both models, an extra first order integral exists. For d = 1, the whole family of 3-body (two-dimensional) Calogero-Moser-Sutherland systems as well as the Tremblay-Turbiner-Winternitz model is reproduced. It is shown that a straightforward generalization of the 3-body (rational) Calogero model to d > 1 leads to two primitive quasi
Efimov states and bound state properties in selected nuclear and molecular three-body systems
International Nuclear Information System (INIS)
Huber, H.S.
1978-01-01
The search is made among selected three-body systems for possible Efimov state behavior. In order to carry out this analysis of phenomenological potentials a new mathematical approach, the FCM (Faddeev-coordinate-momentum) technique, is developed. The analysis then proceeds through the framework of the Faddeev equations by employing the UPE (unitary pole expansion) to reduce these equations to numerically feasible form. The systems chosen for analysis are the 4 He trimer and the three-α model of 12 C. Efimov states are not found in 12 C, thus answering speculation among nuclear theorists. The 4 He trimer, on the other hand, manifests Efimov states for each potential considered and the characteristics of these states are extensively analyzed. Since Efimov states are predicted by all of the phenomenological potentials considered, these states would seem to be a realistically fundamental property of the 4 He trimer system
On the Fokker-Planck theory of electron three-body recombination
International Nuclear Information System (INIS)
Sayasov, Yu. S.
1977-01-01
The Fokker-Planck theory of electron three-body recombination based on the concept of electron diffusion along the energy scale in the excited hydrogen-like atoms formed in the recombining plasmas, is extended in several respects. 1) An universal formula for population distribution of the excited atoms in strongly ionized plasmas was found under a sole assumption, that the cross-sections for the inelastic atom-electron collisions are governed by the classical impulse approximation. 2) A general Fokker-Planck theory of the recombination in a slightly ionized, two-temperature plasmas was formulated. The recombination coefficients for such plasmas were shown to possess some peculiar properties in case the electronic temperature differs appreciable from the atomic one. A few limitations of the existing schemas for calculation of the recombination kinetics are briefly discussed. (orig.) [de
Shape space figure-8 solution of three body problem with two equal masses
Yu, Guowei
2017-06-01
In a preprint by Montgomery (https://people.ucsc.edu/~rmont/Nbdy.html), the author attempted to prove the existence of a shape space figure-8 solution of the Newtonian three body problem with two equal masses (it looks like a figure 8 in the shape space, which is different from the famous figure-8 solution with three equal masses (Chenciner and Montgomery 2000 Ann. Math. 152 881-901)). Unfortunately there is an error in the proof and the problem is still open. Consider the α-homogeneous Newton-type potential, 1/rα, using action minimization method, we prove the existence of this solution, for α \\in (1, 2) ; for α=1 (the Newtonian potential), an extra condition is required, which unfortunately seems hard to verify at this moment.
Three-Body Collision Contributions to Recombination and Collision-Induced Dissociation. II. Kinetics
International Nuclear Information System (INIS)
Kendrick, Brian; Pack, Russell T.; Walker, Robert B.
1998-01-01
Detailed rate constants for the reaction Ne + Ne + H r e quilibrium Ne 2 + H are generated, and the master equations governing collision-induced dissociation (CID) and recombination are accurately solved numerically. The temperature and pressure dependence are explored. At all pressures, three-body (3B) collisions dominate. The sequential two-body energy-transfer (ET) mechanism gives a rate that is more than a factor of two too small at low pressures and orders of magnitude too small at high pressures. Simpler models are explored; to describe the kinetics they must include direct 3B rates connecting the continuum to the bound states and to the quasibound states. The relevance of the present reaction to more general CID/recombination reactions is discussed. For atomic fragments, the 3B mechanism usually dominates. For diatomic fragments,the 3B and ET mechanism are competitive, and for polyatomic fragments the ET mechanism usually dominates
Asymptotic form of the charge exchange cross section in the three body rearrangement collisions
Omidvar, K.
1975-01-01
A three body general rearrangement collision is considered where the initial and final bound states are described by the hydrogen-like wave functions. Mathematical models are developed to establish the relationships of quantum number, the reduced mass, and the nuclear charge of the final state. It is shown that for the low lying levels, the reciprocal of n cubed scaling law at all incident energies is only approximately satisfied. The case of the symmetric collisions is considered and it is shown that for high n and high incident energy, E, the cross section behaves as the reciprocal of E cubed. Zeros and minima in the differential cross sections in the limit of high n for protons on atomic hydrogen and positrons on atomic hydrogen are given.
Electron capture in proton collisions with alkali atoms as a three-body problem
International Nuclear Information System (INIS)
Avakov, G.V.; Blokhintsev, L.D.; Kadyrov, A.S.; Mukhamedzhanov, A.M.
1992-01-01
A previous paper proposed an approach to the calculation of electron transfer reactions in ion-atomic collisions based on the Faddeev three-body equations written in the Alt-Grassberger-Sandhas form. In the present work this approach is used to describe the electron capture in proton collisions with alkali atoms. The results of calculation of the total and partial cross sections for charge exchange in proton collisions with Li, Na, K and Rb atoms are presented. The calculated total cross sections are in good agreement with experiment for light target atoms. In going over to heavier targets, the theoretical total cross sections, while agreeing in form, tend to be larger than the experimental ones. The calculated partial cross sections for electron capture into the 2s state of the H atom are also in agreement with experiment. Some other partial cross sections were also calculated. (author)
Three-Body Recombination near a Narrow Feshbach Resonance in Li 6
Li, Jiaming; Liu, Ji; Luo, Le; Gao, Bo
2018-05-01
We experimentally measure and theoretically analyze the three-atom recombination rate, L3, around a narrow s -wave magnetic Feshbach resonance of Li 6 - Li 6 at 543.3 G. By examining both the magnetic field dependence and, especially, the temperature dependence of L3 over a wide range of temperatures from a few μ K to above 200 μ K , we show that three-atom recombination through a narrow resonance follows a universal behavior determined by the long-range van der Waals potential and can be described by a set of rate equations in which three-body recombination proceeds via successive pairwise interactions. We expect the underlying physical picture to be applicable not only to narrow s wave resonances, but also to resonances in nonzero partial waves, and not only at ultracold temperatures, but also at much higher temperatures.
Time-frequency analysis of the restricted three-body problem: transport and resonance transitions
International Nuclear Information System (INIS)
Vela-Arevalo, Luz V; Marsden, Jerrold E
2004-01-01
A method of time-frequency analysis based on wavelets is applied to the problem of transport between different regions of the solar system, using the model of the circular restricted three-body problem in both the planar and the spatial versions of the problem. The method is based on the extraction of instantaneous frequencies from the wavelet transform of numerical solutions. Time-varying frequencies provide a good diagnostic tool to discern chaotic trajectories from regular ones, and we can identify resonance islands that greatly affect the dynamics. Good accuracy in the calculation of time-varying frequencies allows us to determine resonance trappings of chaotic trajectories and resonance transitions. We show the relation between resonance transitions and transport in different regions of the phase space
Tails and bridges in the parabolic restricted three-body problem
Barrabés, Esther; Cors, Josep M.; Garcia-Taberner, Laura; Ollé, Mercè
2017-12-01
After a close encounter of two galaxies, bridges and tails can be seen between or around them. A bridge would be a spiral arm between a galaxy and its companion, whereas a tail would correspond to a long and curving set of debris escaping from the galaxy. The goal of this paper is to present a mechanism, applying techniques of dynamical systems theory, that explains the formation of tails and bridges between galaxies in a simple model, the so-called parabolic restricted three-body problem, i.e. we study the motion of a particle under the gravitational influence of two primaries describing parabolic orbits. The equilibrium points and the final evolutions in this problem are recalled,and we show that the invariant manifolds of the collinear equilibrium points and the ones of the collision manifold explain the formation of bridges and tails. Massive numerical simulations are carried out and their application to recover previous results are also analysed.
Measurements of Charmless Three-Body and Quasi-Two-Body B Decays
Energy Technology Data Exchange (ETDEWEB)
Barrera, Barbara
2000-08-28
The authors present preliminary results of a search for several exclusive charmless hadronic B decays from electron-positron annihilation data collected by the BaBar detector near the Upsilon(4S) resonance. These include three-body decay modes with final states h{+-}h{sup minus-plus}h{+-} and h{+-}h{sup minus-plus}pi{sup 0}, and quasi-two-body decay modes with final states X{sup 0}h and X{sup 0}K{sub S}{sup 0}, where h = pi or K and X{sup 0} = eta-prime or omega. They find beta(B{sup 0} --> rho{sup minus-plus}pi{sup {+-}}) = (49{+-}13{sub {minus}5}{sup +6}) x 10{sup {minus}6} and beta(B{sup +} --> eta-prime-K{sup +}) = (62{+-}18{+-}8) x 10{sup {minus}6} and present upper limits for right other decays.
Analysis of the neutralino system in three-body leptonic decays of neutralinos
International Nuclear Information System (INIS)
Choi, S.Y.; Chung, B.C.; Kalinowski, J.; Rolbiecki, K.; Kim, Y.G.
2006-01-01
Neutralinos χ 0 in supersymmetric theories, the spin-1/2 Majorana-type superpartners of the U(1) and SU(2) neutral electroweak gauge bosons and SU(2) neutral Higgs bosons, are expected to be among light supersymmetric particles so that they can be produced copiously via direct pair production and/or from cascade decays of other sparticles such as sleptons at the planned Large Hadron Collider and the prospective International Linear Collider. Considering the prospects of having both highly polarized neutralinos and possibility of reconstructing their decay rest frames, we provide a systematic investigation of the three-body leptonic decays of the neutralinos in the minimal supersymmetric standard model and demonstrate alternative ways for probing the Majorana nature of the neutralinos and CP violation in the neutralino system. (orig.)
Optimized evaporative cooling for sodium Bose-Einstein condensation against three-body loss
International Nuclear Information System (INIS)
Shobu, Takahiko; Yamaoka, Hironobu; Imai, Hiromitsu; Morinaga, Atsuo; Yamashita, Makoto
2011-01-01
We report on a highly efficient evaporative cooling optimized experimentally. We successfully created sodium Bose-Einstein condensates with 6.4x10 7 atoms starting from 6.6x10 9 thermal atoms trapped in a magnetic trap by employing a fast linear sweep of radio frequency at the final stage of evaporative cooling so as to overcome the serious three-body losses. The experimental results such as the cooling trajectory and the condensate growth quantitatively agree with the numerical simulations of evaporative cooling on the basis of the kinetic theory of a Bose gas carefully taking into account our specific experimental conditions. We further discuss theoretically a possibility of producing large condensates, more than 10 8 sodium atoms, by simply increasing the number of initial thermal trapped atoms and the corresponding optimization of evaporative cooling.
Three-body coupled-channel theory of scattering and breakup of light and heavy ions
International Nuclear Information System (INIS)
Kamimura, M.; Kameyama, H.; Kawai, M.; Sakuragi, Y.; Iseri, Y.; Yahiro, M.; Tanifuji, M.
1986-09-01
It is shown that the method of coupled discretized continuum channels (CDCC) based on the three-body model for direct reactions is very successful in explaining the following, recently developed experiments using deuteron, 6 Li and 7 Li projectiles whose breakup threshold energies are very low: (i) Precise measurement of all the possible analyzing powers in elastic scattering of polarized deuteron at 56 MeV, (ii) scattering of polarized deuteron at intermediate energies, (iii) deuteron projectile breakup at 56 MeV, (iv) scattering of polarized 7 Li at 20 and 44 MeV and (v) projectile breakup of 6 Li at 178 MeV and 7 Li at 70 MeV. The CDCC analyses of those data are made transparently with no adjustable parameters. (author)
On an efficient and accurate method to integrate restricted three-body orbits
Murison, Marc A.
1989-01-01
This work is a quantitative analysis of the advantages of the Bulirsch-Stoer (1966) method, demonstrating that this method is certainly worth considering when working with small N dynamical systems. The results, qualitatively suspected by many users, are quantitatively confirmed as follows: (1) the Bulirsch-Stoer extrapolation method is very fast and moderately accurate; (2) regularization of the equations of motion stabilizes the error behavior of the method and is, of course, essential during close approaches; and (3) when applicable, a manifold-correction algorithm reduces numerical errors to the limits of machine accuracy. In addition, for the specific case of the restricted three-body problem, even a small eccentricity for the orbit of the primaries drastically affects the accuracy of integrations, whether regularized or not; the circular restricted problem integrates much more accurately.
Muonic molecules as three-body Coulomb problem in adiabatic approximation
International Nuclear Information System (INIS)
Decker, M.
1994-04-01
The three-body Coulomb problem is treated within the framework of the hyperspherical adiabatic approach. The surface functions are expanded into Faddeev-type components in order to ensure the equivalent representation of all possible two-body contributions. It is shown that this decomposition reduces the numerical effort considerably. The remaining radial equations are solved both in the extreme and the uncoupled adiabatic approximation to determine the binding energies of the systems (dtμ) and (d 3 Heμ). Whereas the ground state is described very well in the uncoupled adiabatic approximation, the excited states should be treated within the coupled adiabatic approximation to obtain good agreement with variational calculations. (orig.)
Attractive evolutionary equilibria
Joosten, Reinoud A.M.G.; Roorda, Berend
2011-01-01
We present attractiveness, a refinement criterion for evolutionary equilibria. Equilibria surviving this criterion are robust to small perturbations of the underlying payoff system or the dynamics at hand. Furthermore, certain attractive equilibria are equivalent to others for certain evolutionary
Solving the three-body Coulomb breakup problem using exterior complex scaling
Energy Technology Data Exchange (ETDEWEB)
McCurdy, C.W.; Baertschy, M.; Rescigno, T.N.
2004-05-17
Electron-impact ionization of the hydrogen atom is the prototypical three-body Coulomb breakup problem in quantum mechanics. The combination of subtle correlation effects and the difficult boundary conditions required to describe two electrons in the continuum have made this one of the outstanding challenges of atomic physics. A complete solution of this problem in the form of a ''reduction to computation'' of all aspects of the physics is given by the application of exterior complex scaling, a modern variant of the mathematical tool of analytic continuation of the electronic coordinates into the complex plane that was used historically to establish the formal analytic properties of the scattering matrix. This review first discusses the essential difficulties of the three-body Coulomb breakup problem in quantum mechanics. It then describes the formal basis of exterior complex scaling of electronic coordinates as well as the details of its numerical implementation using a variety of methods including finite difference, finite elements, discrete variable representations, and B-splines. Given these numerical implementations of exterior complex scaling, the scattering wave function can be generated with arbitrary accuracy on any finite volume in the space of electronic coordinates, but there remains the fundamental problem of extracting the breakup amplitudes from it. Methods are described for evaluating these amplitudes. The question of the volume-dependent overall phase that appears in the formal theory of ionization is resolved. A summary is presented of accurate results that have been obtained for the case of electron-impact ionization of hydrogen as well as a discussion of applications to the double photoionization of helium.
Schultz, Sabine; Rosentritt, Martin; Behr, Michael; Handel, Gerhard
2010-01-01
To compare wear performance and resistance to crack propagation (K1C) of commercial restorative materials and their flowable variations. A potential correlation between three-body wear and fracture toughness, modulus of elasticity, fracture work, Vickers hardness, and filler content was investigated. Seven restoratives (five composites, one ormocer, and one compomer) and their corresponding flowable materials were used to determine and compare the three-body wear with a bolus of millet-seed shells and rice food (Willytec). The wear characteristics were measured by profilometry after 50,000, 100,000, 150,000, and 200,000 loading cycles. The fracture toughness value, K1C (MPam1/2), for each single-edged notched specimen was measured in a three-point bending test (universal testing machine 1446, Zwick). Fracture work and modulus of elasticity were calculated from the load curves. Vickers hardness was measured (HV hardness tester, Zwick) according to DIN 50133. The veneering composite Sinfony (3M ESPE) was used as a reference material. Heavily filled composites experienced less wear than their flowable variations. The nanofiller composites revealed better wear results than hybrid composites, compomers, and ormocers. After 200,000 load cycles, the lowest wear rates were detected for Grandio (14 microm; Voco), and the highest mean values were found for Dyract AP (104 microm; Dentsply DeTrey). The values for fracture toughness (K1C) ranged from 0.82 to 3.64 MPam1/2. Highest K1C data was exhibited by the nanocomposite Nanopaq (Schutz Dental). All tested restorative materials exhibited higher fracture toughness than their low-viscosity variations. The wear resistance of the newer generation composites with incorporated nanofiller or microfiller particles increased to a high extent. Flowables show less resistance against wear and crack propagation because of their lower filler content. The reduced mechanical properties limit their use as a restorative to small noncontact
Attraction and cooperative behavior
Donja Darai; Silvia Grätz
2012-01-01
Being good-looking seems to generate substantial benefits in many social interactions, making the "beauty premium" a not to be underrated economic factor. This paper investigates how physical attractiveness enables people to generate these benefits in the case of cooperation, using field data from a modified one-shot prisoner's dilemma played in a high-stakes television game show. While attractive contestants are not more or less cooperative than less attractive ones, facial attractiveness pr...
Properties of three-body decay functions derived with time-like jet calculus beyond leading order
International Nuclear Information System (INIS)
Sugiura, Tetsuya
2002-01-01
Three-body decay functions in time-like parton branching are calculated using the jet calculus to the next-to-leading logarithmic (NLL) order in perturbative quantum chromodynamics (QCD). The phase space contributions from each of the ladder diagrams and interference diagrams are presented. We correct part of the results for the three-body decay functions calculated previously by two groups. Employing our new results, the properties of the three-body decay functions in the regions of soft partons are examined numerically. Furthermore, we examine the contribution of the three-body decay functions modified by the restriction resulting from the kinematical boundary of the phase space for two-body decay in the parton shower model. This restriction leads to some problems for the parton shower model. For this reason, we propose a new restriction introduced by the kinematical boundary of the phase space for two-body decay. (author)
Face inversion increases attractiveness.
Leder, Helmut; Goller, Juergen; Forster, Michael; Schlageter, Lena; Paul, Matthew A
2017-07-01
Assessing facial attractiveness is a ubiquitous, inherent, and hard-wired phenomenon in everyday interactions. As such, it has highly adapted to the default way that faces are typically processed: viewing faces in upright orientation. By inverting faces, we can disrupt this default mode, and study how facial attractiveness is assessed. Faces, rotated at 90 (tilting to either side) and 180°, were rated on attractiveness and distinctiveness scales. For both orientations, we found that faces were rated more attractive and less distinctive than upright faces. Importantly, these effects were more pronounced for faces rated low in upright orientation, and smaller for highly attractive faces. In other words, the less attractive a face was, the more it gained in attractiveness by inversion or rotation. Based on these findings, we argue that facial attractiveness assessments might not rely on the presence of attractive facial characteristics, but on the absence of distinctive, unattractive characteristics. These unattractive characteristics are potentially weighed against an individual, attractive prototype in assessing facial attractiveness. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Observation of the Borromean Three-Body Förster Resonances for Three Interacting Rb Rydberg Atoms.
Tretyakov, D B; Beterov, I I; Yakshina, E A; Entin, V M; Ryabtsev, I I; Cheinet, P; Pillet, P
2017-10-27
Three-body Förster resonances at long-range interactions of Rydberg atoms were first predicted and observed in Cs Rydberg atoms by Faoro et al. [Nat. Commun. 6, 8173 (2015)NCAOBW2041-172310.1038/ncomms9173]. In these resonances, one of the atoms carries away an energy excess preventing the two-body resonance, leading thus to a Borromean type of Förster energy transfer. But they were in fact observed as the average signal for the large number of atoms N≫1. In this Letter, we report on the first experimental observation of the three-body Förster resonances 3×nP_{3/2}(|M|)→nS_{1/2}+(n+1)S_{1/2}+nP_{3/2}(|M^{*}|) in a few Rb Rydberg atoms with n=36, 37. We have found here clear evidence that there is no signature of the three-body Förster resonance for exactly two interacting Rydberg atoms, while it is present for N=3-5 atoms. This demonstrates the assumption that three-body resonances can generalize to any Rydberg atom. As such resonance represents an effective three-body operator, it can be used to directly control the three-body interactions in quantum simulations and quantum information processing with Rydberg atoms.
Equilibria of the three-body problem with rigid dumb-bell satellite
International Nuclear Information System (INIS)
Elipe, A.; Palacios, M.; Pretka-Ziomek, H.
2008-01-01
This paper is concerned with the orbital-rotational motion of an asymmetric dumb-bell (two masses with fixed distance among them) under the attraction of a central body. For this model, we find some equilibria and give sufficient conditions for their stability
Many-body forces and stability of the alkaline-earth tetramers
International Nuclear Information System (INIS)
Diaz-Torrejon, C.C.; Kaplan, Ilya G.
2011-01-01
Graphical abstract: Many-body forces effect. In a three-particle system, the two-body interaction energies depend upon coordinates of all three particles. The comparative study of the interaction energy and its many-body decomposition for alkaline-earths tetramers Be 4 , Mg 4 , and Ca 4 at the all-electron CCSD(T)/aug-cc-pVQZ level is performed. For study of dependence of the binding energy and the orbital population on the cluster size the corresponding dimers and trimers were also calculated at the same level of theory. In comparison with weakly bound dimers, the binding energy in trimers and, especially, in tetramers drastically increases; e.g., E b /N in Be 3 is 7 times larger and in Be 4 is 18.4 times larger than in Be 2 . This sharp increase is explained as a manifestation of many-body forces. The trimers and tetramers are stabilized by the three-body forces, whereas the two- and four-body forces are repulsive. The attractive contribution to the three-body forces has a three-atom electron exchange origin. The natural bond orbital (NBO) population analysis reveals a relatively large np-population in trimers and tetramers. The population of the valence np-orbitals leads to the sp-hybridization providing the covalent bonding. Research highlights: → The alkaline-earths trimers and tetramers are stabilized by the three-body forces. → Two- and four-body forces are repulsive for trimers and tetramers. → The attractive contribution to the three-body forces has a three-atom electron exchange origin. → The population of the np-orbitals leads to the sp-hybridization providing the covalent bonding. - Abstract: The comparative study of the interaction energy and its many-body decomposition for Be 4 , Mg 4 , and Ca 4 at the all-electron CCSD(T)/aug-cc-pVQZ level is performed. For study of dependence of the binding energy and the orbital population on the cluster size the corresponding dimers and trimers were also calculated at the same level of theory. In
Three-body charmful baryonic B decays B-bar→D(D*)NN-bar
International Nuclear Information System (INIS)
Cheng Haiyang; Yang Kweichou
2002-01-01
We study the charmful three-body baryonic B decays B-bar→D ( * ) NN-bar: the color-allowed modes B-bar 0 →D ( * )+ np-bar and the color-suppressed ones B-bar 0 →D ( * )0 pp-bar. While the D* + /D + production ratio is predicted to be of order 3, it is found that D 0 pp-bar has a similar rate as D* 0 pp-bar. It is pointed out that B-bar 0 →D(D*)NN-bar are dominated by the nucleon vector current or by vector meson intermediate states, whereas B-bar 0 →D 0 pp-bar proceeds mainly via the exchange of the axial-vector intermediate state a 1 (1260). The study of the NN-bar invariant mass distribution in general indicates a threshold baryon pair production; that is, a recoil charmed meson accompanied by a low mass baryon pair except that the spectrum of D 0 pp-bar has a hump at large pp-bar invariant mass m pp-bar ∼3.0 GeV
Three-body correlations in the decay of $^{10}$He and $^{13}$Li
Jonson, B; Cortina-Gil, D; Simon, H; Emling, H; Nyman, G; Nilsson, T; Johansson, H T; Borge, M J G; Paschalis, S; Muenzenberg, G; Zhukov, M V; Weick, H; Pramanik, U Datta; LeBleis, T; Meister, M; Reifarth, R; Chulkov, L V; Lantz, M; Riisager, K; Mahata, K; Suemmerer, K; Langer, C; Chatillon, A; Richter, A; Kulessa, R; Palit, R; Aksyutina, Yu; Geissel, H; Aumann, T; Shulgina, N B; Prokopowicz, W; Forssen, C; Ickert, G; Fynbo, H O U; Tengblad, O; Boretzky, K
2010-01-01
The very exotic nuclear resonance systems. He-10 and Li-13, are produced in proton-knockout reactions from relativistic beams of Li-11 and Be-14. The experimentally determined energy and angular correlations between their decay products, He-8 + n + n and Li-11 + n + n, are analyzed using an expansion of decay amplitudes in a restricted set of hyperspherical harmonics. By considering only a small number of terms it is possible to extract the expansion coefficients directly from the experimental three-body correlations. This provides a model-independent way of getting information about the decay process. on the structure of the decaying nucleus and on the quantum characteristics of the binary subsystems The results show that the He-8 + n + n relative-energy spectrum can be interpreted as consisting of two resonances, an I-pi = 0(+) ground state and an excited I-pi = 2(+) state. The Li-11 + n + n relative-energy spectrum is interpreted as an I-pi = 3/2(-) ground state overlapping with excited states having a str...
TMD parton distributions based on three-body decay functions in NLL order of QCD
International Nuclear Information System (INIS)
Tanaka, Hidekazu
2015-01-01
Three-body decay functions in space-like parton branches are implemented to evaluate transverse-momentum-dependent (TMD) parton distribution functions in the next-to-leading logarithmic (NLL) order of quantum chromodynamics (QCD). Interference contributions due to the next-to-leading-order terms are taken into account for the evaluation of the transverse momenta in initial state parton radiations. Some properties of the decay functions are also examined. As an example, the calculated results are compared with those evaluated by an algorithm proposed in [M. A. Kimber, A. D. Martin, and M. G. Ryskin, Eur. Phys. J. C 12, 655 (2000)], [M. A. Kimber, A. D. Martin, and M. G. Ryskin, Phys. Rev. D 63, 11402 (2001)], [G. Watt, A. D. Martin, and M. G. Ryskin, Eur. Phys. J. C 31, 73 (2003)], and [A. D. Martin, M. G. Ryskin, and G. Watt, Eur. Phys. J. C 66, 167 (2010)], in which the TMD parton distributions are defined based on the k t -factorization method with angular ordering conditions due to interference effects
Salomone, Salvatore; Piazza, Cateno; Vitale, Daniela Cristina; Cardì, Francesco; Gugliotta, Barbara; Drago, Filippo
2014-02-01
To assess the relative bioavailability of a new subcutaneous (SC) diclofenac hydroxypropyl b-cyclodextrin (HPbCD) formulation administered to three body sites: quadriceps, gluteus, and abdomen. This was a pilot, single-dose, randomized, three-way crossover relative bioavailability study. A total of 12 healthy subjects received a single SC injection of diclofenac HPbCD 50 mg/1 mL in the quadriceps, gluteus, or abdomen. The AUC was comparable after SC diclofenac HPbCD in the quadriceps, gluteus, and abdomen. The Cmax was comparable after SC administration in the quadriceps or abdomen, and ~ 17% higher in the gluteus. The absorption was rapid (30 minutes) after administration of the treatment at any site. The treatment was well tolerated. The relative bioavailability of SC diclofenac HPbCD was comparable when administered to the quadriceps, gluteus, and abdomen. The new diclofenac formulation can therefore be administered subcutaneously to any of these sites without clinically significant differences. A further adequately powered study would be necessary to reveal any differences among injection sites in terms of peak plasma concentration.
Directory of Open Access Journals (Sweden)
Hemanth Rajashekaraiah
2014-01-01
Full Text Available Various amounts of short fibers (glass and carbon and particulate fillers like polytetrafluoroethylene (PTFE, silicon carbide (SiC, and alumina (Al2O3 were systematically introduced into the thermoplastic copolyester elastomer (TCE matrix for reinforcement purpose. The mechanical properties such as storage modulus, loss modulus, and Tan δ by dynamic mechanical analysis (DMA and three-body abrasive wear performance on a dry sand rubber wheel abrasion tester have been investigated. For abrasive wear study, the experiments were planned according to L27 orthogonal array by considering three factors and three levels. The complex moduli for TCE hybrid composites were pushed to a higher level relative to the TCE filled PTFE composite. At lower temperatures (in the glassy region, the storage modulus increases with increase in wt.% of reinforcement (fiber + fillers and the value is maximum for the composite with 40 wt.% reinforcement. The loss modulus and damping peaks were also found to be higher by the incorporation of SiC and Al2O3 microfillers. The routine abrasive wear test results indicated that TCE filled PTFE composite exhibited better abrasion resistance. Improvements in the abrasion resistance, however, have not been achieved by short-fiber and particlaute filler reinforcements. From the Taguchi’s experimental findings, optimal combination of control factors were obtained for minimum wear volume and also predictive correlations were proposed. Further, the worn surface morphology of the samples was discussed.
Radiative and three-body recombination in the Alcator C-Mod divertor
International Nuclear Information System (INIS)
Lumma, D.; Terry, J.L.; Lipschultz, B.
1997-01-01
Significant recombination of the majority ion species has been observed in the divertor region of Alcator C-Mod [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)] under detached conditions. This determination is made by analysis of the visible spectrum from the divertor, in particular the Balmer series line emission and the observed recombination continuum, including an apparent recombination edge at ∼375 nm. The analysis shows that the electron temperature in the recombining plasma is 0.8 endash 1.5 eV. The measured volume recombination rate is comparable to the rate of ion collection at the divertor plates. The dominant recombination mechanism is three-body recombination into excited states (e+e+D + Right-arrow D 0 +e), although radiative recombination (e+D + Right-arrow D 0 +hν) contributes ∼5% to the total rate. Analysis of the Balmer series line intensities (from n upper =3 through 10) shows that the upper levels of these transitions are populated primarily by recombination. Thus the brightnesses of the Balmer series (and Lyman series) are directly related to the recombination rate. copyright 1997 American Institute of Physics
Studies of $C\\!P$-violation in charmless three-body $b$-hadron decays
AUTHOR|(INSPIRE)INSPIRE-00401396
Violation of combined charge and parity inversion ($C\\!P$) is a property of the Standard Model that results in a fundamental difference between particles and anti-particles. The single source of $C\\!P$-violation in the Standard Model is insufficient to explain the dominance of matter over anti-matter in the contemporary universe, however, thus far, there has been no clear observation of $C\\!P$-violation beyond the Standard Model. Constraints on various $C\\!P$-violating observables are now precise enough that these represent sensitive tests for physics beyond the Standard Model. This thesis firstly documents the observation of two three-body $b$-baryon decays, and measurements of their phase-space integrated $C\\!P$-asymmetries, which are some of the first to be performed on baryon decays. These measurements provide useful information on hadronisation in $b$-baryon decays, on the intermediate decay dynamics, and give a potential avenue to search for $C\\!P$-violation in baryon decays. An amplitude analysis of th...
Three-body interactions in liquid and solid hydrogen: Evidence from vibrational spectroscopy
Hinde, Robert
2008-03-01
In the cryogenic low-density liquid and solid phases of H2 and D2, the H2 and D2 molecules retain good rotational and vibrational quantum numbers that characterize their internal degrees of freedom. High-resolution infrared and Raman spectroscopic experiments provide extremely sensitive probes of these degrees of freedom. We present here fully-first-principles calculations of the infrared and Raman spectra of liquid and solid H2 and D2, calculations that employ a high-quality six-dimensional coupled-cluster H2-H2 potential energy surface and quantum Monte Carlo treatments of the single-molecule translational degrees of freedom. The computed spectra agree very well with experimental results once we include three-body interactions among the molecules, interactions which we also compute using coupled-cluster quantum chemical methods. We predict the vibrational spectra of liquid and solid H2 at several temperatures and densities to provide a framework for interpreting recent experiments designed to search for superfluid behavior in small H2 droplets. We also present preliminary calculations of the spectra of mixed H2/D2 solids that show how positional disorder affects the spectral line shapes in these systems.
Asymptotic form of the charge-exchange cross section in three-body rearrangement collisions
Omidvar, K.
1975-01-01
A three-body general-type rearrangement collision is considered in which the initial and final bound states are described by hydrogen-like wave functions. It is shown that the charge-exchange amplitude in the first Born approximation can be expanded at all incident energies in terms of the inverse powers of the principal quantum number (n). By expanding the exchange amplitude in this way, it is demonstrated conclusively that the cross section for capture into the s, p, and d states as well as for the sum over all the angular-momentum states is proportional to 1/n-cubed plus terms proportional to higher inverse odd powers of n. It is found that the low-lying levels cannot be scaled to the 1/n-cubed law irrespective of the value of the incident energy except in the case of capture into the s states in accordance with the Oppenheimer-Brinkman-Kramers approximation. Zeros and minima in the differential cross sections are given in the limit of high principal quantum number for electron capture by protons from atomic hydrogen and for positronium formation by proton-atomic hydrogen collisions.
Three-body calculation of two-body threshold electrodisintegration of 3He and 3H
International Nuclear Information System (INIS)
Heimbach, C.R.; Lehman, D.R.; O'Connell, J.S.
1977-01-01
Threshold two-body electrodisintegration of 3 He and 3 H is investigated within the context of exact three-body theory. The calculations performed are based on the formalism of Gibson and Lehman. Careful consideration is given to the singularities of the disintegration Born amplitude for this case, since the momentum transfer is not zero, to assure validity of the numerical methods. Calculated results are compared with all the latest threshold 3 He electrodisintegration data which samples a range of scattered-electron angles, 92.6 0 0 , and incident electron energies, 40 MeV 0 3 H electrodisintegration for some of the same kinematics. The mechanism for the sharp rise as a function of excitation energy in the (e,e') cross section for theta/sub e/ approx. 90 0 due to the 2 S → 2 S monopole transition from Coulomb scattering is singled out by examination of the contributions to the Coulomb doublet amplitude. A similar analysis is carried out for the doublet and quartet transverse amplitudes where the 2 S → 4 P magnetic quadrupole transition dominates for excitation energies less than 20 MeV
Study of charmless three-body decays of neutral B mesons with the LHCb spectrometer
Sobczak, Krzysztof Grzegorz
This thesis describes an exploratory work on three-body charmless neutral $B$ mesons decays containing either a $K_S$ or $\\pi^0$. The events are reconstructed with the LHCb spectrometer installed at Cern (Geneva, CH) recording the proton-proton collisions delivered by the Large Hadron Collider (LHC). The phenomenology of such modes is rich and covers the possibility to measure all angles of the unitarity triangle linked to the Cabibbo-Kobayashi-Maskawa (CKM) matrix. The single example of the $\\gamma$ measurement is explored in this document. The LHC accelerator and the most relevant sub-detector elements of the LHCb spectrometer are described in details. In particular, emphasis is given to the calorimetry system for which the calibration and alignment of the PreShower (PRS) of the electromagnetic calorimeter has been performed. We used particles at minimum ionisation deposit for such a task. The calibration results until year 2011 are reported as well as the method of the PS alignment with respect to the tra...
A study on basic theory for CDCC method for three-body model of deuteron scattering
International Nuclear Information System (INIS)
Kawai, Mitsuji
1988-01-01
Recent studies have revealed that the CDCC method is valid for treating the decomposition process involved in deuteron scattering on the basis of a three-body model. However, theoretical support has not been developed for this method. The present study is aimed at determining whether a solution by the CDCC method can be obtained 'correctly' from a 'realistic' model Hamiltonian for deuteron scattering. Some researchers have recently pointed out that there are some problems with the conventional CDCC calculation procedure in view of the general scattering theory. These problems are associated with asymptotic froms of the wave functions, convergence of calculations, and boundary conditions. Considerations show that the problem with asymptotic forms of the wave function is not a fatal defect, though some compromise is necessary. The problem with the convergence of calculations is not very serious either. Discussions are made of the handling of boundary conditions. Thus, the present study indicates that the CDCC method can be applied satisfactorily to actual deuteron scattering, and that the model wave function for the CDCC method is consistent with the model Hamiltonian. (Nogami, K.)
AMS-02 positron excess and indirect detection of three-body decaying dark matter
Energy Technology Data Exchange (ETDEWEB)
Cheng, Hsin-Chia [Department of Physics, University of California, Davis, CA 95616 (United States); Huang, Wei-Chih [Fakultät für Physik, Technische Universität Dortmund, 44221 Dortmund (Germany); Huang, Xiaoyuan [Physik-Department T30d, Technische Universität München, James-Franck-Straße, D-85748 Garching (Germany); Low, Ian [High Energy Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Tsai, Yue-Lin Sming [Kavli IPMU (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Yuan, Qiang, E-mail: cheng@physics.ucdavis.edu, E-mail: wei-chih.huang@tu-dortmund.de, E-mail: huangxiaoyuan@gmail.com, E-mail: ilow@northwestern.edu, E-mail: smingtsai@gmail.com, E-mail: yuanq@pmo.ac.cn [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)
2017-03-01
We consider indirect detection of meta-stable dark matter particles decaying into a stable neutral particle and a pair of standard model fermions. Due to the softer energy spectra from the three-body decay, such models could potentially explain the AMS-02 positron excess without being constrained by the Fermi-LAT gamma-ray data and the cosmic ray anti-proton measurements. We scrutinize over different final state fermions, paying special attention to handling of the cosmic ray background and including various contributions from cosmic ray propagation with the help of the LIKEDM package. It is found that primary decays into an electron-positron pair and a stable neutral particle could give rise to the AMS-02 positron excess and, at the same time, stay unscathed against the gamma-ray and anti-proton constraints. Decays to a muon pair or a mixed flavor electron-muon pair may also be viable depending on the propagation models. Decays to all other standard model fermions are severely disfavored.
Three-body correlations in the decay of {sup 10}He and {sup 13}Li
Energy Technology Data Exchange (ETDEWEB)
Johansson, H.T. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Aksyutina, Yu. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); ExtreMe Matter Institute, EMMI, GSI, D-64291 Darmstadt (Germany); Aumann, T.; Boretzky, K. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Borge, M.J.G. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Chatillon, A. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Chulkov, L.V. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Kurchatov Institute, RU-123182 Moscow (Russian Federation); Cortina-Gil, D. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); University of Santiago de Compostela, 15706 Santiago de Compostela (Spain); Datta Pramanik, U. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Emling, H. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Forssen, C. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Fynbo, H.O.U. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Geissel, H.; Ickert, G. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Jonson, B., E-mail: Bjorn.Jonson@chalmers.s [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Physics Department, CERN, CH-1211 Geneve 23 (Switzerland); Kulessa, R. [Instytut Fizyki, Universytet Jagiellonski, PL-30-059 Krakow (Poland); Langer, C. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Lantz, M. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); LeBleis, T.; Mahata, K. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany)
2010-12-01
The very exotic nuclear resonance systems, {sup 10}He and {sup 13}Li, are produced in proton-knockout reactions from relativistic beams of {sup 11}Li and {sup 14}Be. The experimentally determined energy and angular correlations between their decay products, {sup 8}He+n+n and {sup 11}Li+n+n, are analyzed using an expansion of decay amplitudes in a restricted set of hyperspherical harmonics. By considering only a small number of terms it is possible to extract the expansion coefficients directly from the experimental three-body correlations. This provides a model-independent way of getting information about the decay process, on the structure of the decaying nucleus and on the quantum characteristics of the binary subsystems. The results show that the {sup 8}He+n+n relative-energy spectrum can be interpreted as consisting of two resonances, an I{sup {pi}=}0{sup +} ground state and an excited I{sup {pi}=}2{sup +} state. The {sup 11}Li+n+n relative-energy spectrum is interpreted as an I{sup {pi}=}3/2{sup -} ground state overlapping with excited states having a structure similar to the 2{sup +} state in {sup 10}He but spread over several states due to the coupling to the I{sup {pi}=}3/2{sup -} core. The {sup 13}Li data also give evidence for a contribution of a configuration where the two neutrons occupy the d-shell.
Evidence of three-body correlation functions in Rb+ and Sr2+ acetonitrile solutions
D'Angelo, P.; Pavel, N. V.
1999-09-01
The local structure of Sr2+ and Rb+ ions in acetonitrile has been investigated by x-ray absorption spectroscopy (XAS) and molecular dynamics simulations. The extended x-ray absorption fine structure above the Sr and Rb K edges has been interpreted in the framework of multiple scattering (MS) formalism and, for the first time, clear evidence of MS contributions has been found in noncomplexing ion solutions. Molecular dynamics has been used to generate the partial pair and triangular distribution functions from which model χ(k) signals have been constructed. The Sr2+ and Rb+ acetonitrile pair distribution functions show very sharp and well-defined first peaks indicating the presence of a well organized first solvation shell. Most of the linear acetonitrile molecules have been found to be distributed like hedgehog spines around the Sr2+ and Rb+ ions. The presence of three-body correlations has been singled out by the existence of well-defined peaks in the triangular configurations. Excellent agreement has been found between the theoretical and experimental data enforcing the reliability of the interatomic potentials used in the simulations. These results demonstrate the ability of the XAS technique in probing the higher-order correlation functions in solution.
Energy Technology Data Exchange (ETDEWEB)
Efremenko, Vasily; Pastukhova, Tatiana; Chabak, Yuliia; Efremenko, Alexey [Pryazovskyi State Technical Univ., Mariupol (Ukraine); Shimizu, Kazumichi; Kusumoto, Kenta [Muroran Institute of Technology, Hokkaido (Japan); Brykov, Michail [Zaporozhye National Technical Univ., Zaporozhye (Ukraine)
2018-02-15
The effect of heat treatment and chromium contents (up to 9.1 wt.%) on the wear resistance of spheroidal carbide cast iron (9.5 wt.% V) was studied using optical and scanning electron microscopy, X-ray diffractometry, dilatometry and three-body abrasive testing. It was found that quenching from 760 C and 920 C improved the alloys' wear resistance compared to the as-cast state due to the formation of metastable austenite transforming into martensite under abrasion. The wear characteristics of alloys studied are 1.6 - 2.3 times higher than that of reference cast iron (12 wt.% V) having stable austenitic matrix. Chromium addition decreases surface damage due to the formation of M{sub 7}C{sub 3} carbides, while it reduces wear resistance owing to austenite stabilization to abrasion-induced martensite transformation. The superposition of these factors results in decreasing the alloys' wear behaviour with chromium content increase.
The mechanism of three-body process of energy transfer from excited xenon atoms to molecules
International Nuclear Information System (INIS)
Wojciechowski, K.; Forys, M.
1999-01-01
The mechanism of energy transfer from Xe(6 s[3/2] 1 ) resonance state (E=8.44 eV) and higher excited Xe(6p, 6p', 6 d) atoms produced in pulse radiolysis to molecules have been discussed. The analysis of the kinetic data for these processes shows that in the sensitized photolysis and radiolysis of Xe-M mixtures the excited atoms decay in 'ordinary' two-body reaction: Xe(6s[3/2] 1 0 )+M→products (r.1) and in fast 'accelerated' third order process: Xe(6s[3/2] 1 0 )+M+Xe→products (r.2) The discussion shows that three-body process occurs via reactions: Xe(6s[3/2] 1 0 )+Xe k w ↔ k d Xe 2 ** (r.2a) Xe 2 **+M k q →[Xe 2 M]*→products (r.2b) It was shown that this mechanism concerns also higher excited Xe atoms and can explain a similar process in He-M mixtures and suggests that it is a general mechanism of energy transfer in all irradiated rare gas-molecule systems
Studies of continuum states in${16}$ Ne using three-body correlation techniques
Marganiec, J; Aksouh, F; Aksyutina, Yu; Alvarez-Pol, H; Aumann, T; Beceiro-Novo, S; Boretzky, K; Borge, M J G; Chartier, M; Chatillon, A; Chulkov, L V; Cortina-Gil, D; Emling, H; Ershova, O; Fraile, L M; Fynbo, H O U; Galaviz, D; Geissel, H; Heil, M; Hoffmann, D H H; Hoffmann, J; Johansson, H T; Jonson, B; Karagiannis, C; Kiselev, O A; Kratz, J V; Kulessa, R; Kurz, N; Langer, C; Lantz, M; Le Bleis, T; Lemmon, R; Litvinov, Yu A; Mahata, K; Müntz, C; Nilsson, T; Nociforo, C; Nyman, G; Ott, W; Panin, V; Paschalis, S; Perea, A; Plag, R; Reifarth, R; Richter, A; Rodriguez-Tajes, C; Rossi, D; Riisager, K; Savran, D; Schrieder, G; Simon, H; Stroth, J; Sümmerer, K; Tengblad, O; Weick, H; Wiescher, M; Wimmer, C; Zhukov, M V
2015-01-01
Two-proton decay of the unbound $ T_{z} =-2$ nucleus$^{16}$Ne , produced in one-neutron knockout from a 500 MeV/u$^{17}$Ne beam, has been studied at GSI. The ground state, at a resonance energy 1.388(15) MeV, ( $ \\Gamma =0.082(15)$ MeV) above the$^{14}$O +p+p threshold, and two narrow resonances at $ E_{r} =3.220(46)$ MeV and 7.57(6) MeV have been investigated. A comparison of the energy difference between the first excited 2$^{+}$ state and the 0$^{+}$ ground state in$^{16}$Ne with its mirror nucleus$^{16}$C reveals a small Thomas-Ehrman shift (TES) of $ +70(46)$ keV. A trend of the TES for the T = 2 quintet is obtained by completing the known data with a prediction for$^{16}$F obtained from an IMME analysis. The decay mechanisms of the observed three resonances were revealed from an analysis of the energy and angular correlations of the$^{14}$O +p+p decay products. The ground state decay can be considered as a genuine three-body (democratic) mode and the excited states decay sequentially via states in the i...
A non-orthogonal harmonic-oscillator basis for three-body problems
International Nuclear Information System (INIS)
Agrello, D.A.; Aguilera-Navarro, V.C.; Chacon, E.
1979-01-01
A set of harmonic-oscillator states suitable for the representation of the wave function of the bound states of a system of three identical particles, is presented. As an illustration of the possibilities of the states defined in this paper, they are applied in a variational determination of the lowest symmetric S state of 12 C, in the model of three structureless α particles interacting through the Coulomb force plus a phenomenological two-body force. (author) [pt
Three-body dissociations: The photodissociation of dimethyl sulfoxide at 193 nm
Energy Technology Data Exchange (ETDEWEB)
Blank, D.A.; North, S.W.; Stranges, D. [Lawrence Berkeley National Lab., CA (United States)] [and others
1997-04-01
When a molecule with two equivalent chemical bonds is excited above the threshold for dissociation of both bonds, how the rupture of the two bonds is temporally coupled becomes a salient question. Following absorption at 193 nm dimethyl sulfoxide (CH{sub 3}SOCH{sub 3}) contains enough energy to rupture both C-S bonds. This can happen in a stepwise (reaction 1) or concerted (reaction 2) fashion where the authors use rotation of the SOCH{sub 3} intermediate prior to dissociation to define a stepwise dissociation: (1) CH{sub 3}SOCH{sub 3} {r_arrow} 2CH{sub 3} + SO; (2a) CH{sub 3}SOCH{sub 3} {r_arrow} CH{sub 3} + SOCH{sub 3}; and (2b) SOCH{sub 3} {r_arrow} SO + CH{sub 3}. Recently, the dissociation of dimethyl sulfoxide following absorption at 193 nm was suggested to involve simultaneous cleavage of both C-S bonds on an excited electronic surface. This conclusion was inferred from laser induced fluorescence (LIF) and resonant multiphoton ionization (2+1 REMPI) measurements of the internal energy content in the CH{sub 3} and SO photoproducts and a near unity quantum yield measured for SO. Since this type of concerted three body dissociation is very interesting and a rather rare event in photodissociation dynamics, the authors chose to investigate this system using the technique of photofragment translational spectroscopy at beamline 9.0.2.1. The soft photoionization provided by the VUV undulator radiation allowed the authors to probe the SOCH{sub 3} intermediate which had not been previously observed and provided good evidence that the dissociation of dimethyl sulfoxide primarily proceeds via a two step dissociation, reaction 2.
Two massive stars possibly ejected from NGC 3603 via a three-body encounter
Gvaramadze, V. V.; Kniazev, A. Y.; Chené, A.-N.; Schnurr, O.
2013-03-01
We report the discovery of a bow-shock-producing star in the vicinity of the young massive star cluster NGC 3603 using archival data of the Spitzer Space Telescope. Follow-up optical spectroscopy of this star with Gemini-South led to its classification as O6 V. The orientation of the bow shock and the distance to the star (based on its spectral type) suggest that the star was expelled from the cluster, while the young age of the cluster (˜2 Myr) implies that the ejection was caused by a dynamical few-body encounter in the cluster's core. The relative position on the sky of the O6 V star and a recently discovered O2 If*/WN6 star (located on the opposite side of NGC 3603) allows us to propose that both objects were ejected from the cluster via the same dynamical event - a three-body encounter between a single (O6 V) star and a massive binary (now the O2 If*/WN6 star). If our proposal is correct, then one can `weigh' the O2 If*/WN6 star using the conservation of the linear momentum. Given a mass of the O6 V star of ≈30 M⊙, we found that at the moment of ejection the mass of the O2 If*/WN6 star was ≈175 M⊙. Moreover, the observed X-ray luminosity of the O2 If*/WN6 star (typical of a single star) suggests that the components of this originally binary system have merged (e.g., because of encounter hardening).
Three-body dissociations: The photodissociation of dimethyl sulfoxide at 193 nm
International Nuclear Information System (INIS)
Blank, D.A.; North, S.W.; Stranges, D.
1997-01-01
When a molecule with two equivalent chemical bonds is excited above the threshold for dissociation of both bonds, how the rupture of the two bonds is temporally coupled becomes a salient question. Following absorption at 193 nm dimethyl sulfoxide (CH 3 SOCH 3 ) contains enough energy to rupture both C-S bonds. This can happen in a stepwise (reaction 1) or concerted (reaction 2) fashion where the authors use rotation of the SOCH 3 intermediate prior to dissociation to define a stepwise dissociation: (1) CH 3 SOCH 3 → 2CH 3 + SO; (2a) CH 3 SOCH 3 → CH 3 + SOCH 3 ; and (2b) SOCH 3 → SO + CH 3 . Recently, the dissociation of dimethyl sulfoxide following absorption at 193 nm was suggested to involve simultaneous cleavage of both C-S bonds on an excited electronic surface. This conclusion was inferred from laser induced fluorescence (LIF) and resonant multiphoton ionization (2+1 REMPI) measurements of the internal energy content in the CH 3 and SO photoproducts and a near unity quantum yield measured for SO. Since this type of concerted three body dissociation is very interesting and a rather rare event in photodissociation dynamics, the authors chose to investigate this system using the technique of photofragment translational spectroscopy at beamline 9.0.2.1. The soft photoionization provided by the VUV undulator radiation allowed the authors to probe the SOCH 3 intermediate which had not been previously observed and provided good evidence that the dissociation of dimethyl sulfoxide primarily proceeds via a two step dissociation, reaction 2
Intelligence and Physical Attractiveness
Kanazawa, Satoshi
2011-01-01
This brief research note aims to estimate the magnitude of the association between general intelligence and physical attractiveness with large nationally representative samples from two nations. In the United Kingdom, attractive children are more intelligent by 12.4 IQ points (r=0.381), whereas in the United States, the correlation between…
Assertiveness and Physical Attractiveness.
Kleim, David M.; And Others
Earlier research investigating the relationship between physical attractiveness and assertiveness found that physically attractive females were more assertive than other females. To investigate this relationship further and to broaden the scope of the study, 69 students were videotaped in groups of five to ten while responding to open-ended…
Studies of continuum states in {sup 16}Ne using three-body correlation techniques
Energy Technology Data Exchange (ETDEWEB)
Marganiec, J. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Research Division GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Wamers, F. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Research Division GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Frankfurt Institute for Advanced Studies FIAS, Frankfurt am Main (Germany); Aksouh, F.; Aksyutina, Yu.; Boretzky, K.; Chatillon, A.; Emling, H.; Geissel, H.; Heil, M.; Hoffmann, J.; Karagiannis, C.; Kiselev, O.A.; Kurz, N.; Litvinov, Yu.A.; Muentz, C.; Nociforo, C.; Ott, W.; Rossi, D.; Simon, H.; Suemmerer, K.; Weick, H. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Alvarez-Pol, H.; Beceiro-Novo, S.; Cortina-Gil, D.; Rodriguez-Tajes, C. [Universidade de Santiago de Compostela, Grupo de Fisica Nuclear, Santiago de Compostela (Spain); Aumann, T.; Panin, V. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Borge, M.J.G. [CERN, ISOLDE-EP, Geneva (Switzerland); CSIC, Instituto de Estructura de la Materia, Madrid (Spain); Chartier, M. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Chulkov, L.V. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Kurchatov Institute, Moscow (Russian Federation); Ershova, O.; Langer, C.; Plag, R.; Reifarth, R.; Wimmer, C. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe Universitaet, Institut fuer Angewandte Physik, Frankfurt am Main (Germany); Fraile, L.M. [Universidad Complutense de Madrid, CEI Moncloa, Grupo de Fisica Nuclear, FAMN, Madrid (Spain); Fynbo, H.O.U.; Riisager, K. [University of Aarhus, Department of Physics and Astronomy, Aarhus (Denmark); Galaviz, D.; Perea, A.; Tengblad, O. [CSIC, Instituto de Estructura de la Materia, Madrid (Spain); Hoffmann, D.H.H.; Richter, A.; Schrieder, G. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Johansson, H.T.; Jonson, B.; Nilsson, T.; Nyman, G.; Zhukov, M.V. [Chalmers Tekniska Hoegskola, Fundamental Fysik, Goeteborg (Sweden); Kratz, J.V. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Kernchemie, Mainz (Germany); Kulessa, R. [Uniwersytet Jagellonski, Instytut Fizyki, Krakov (Poland); Lantz, M. [Uppsala Universitet, Institutionen foer fysik och astronomi, Uppsala (Sweden); Le Bleis, T. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Technische Universitaet Muenchen, Physik-Department E12, Garching (Germany); Lemmon, R. [STFC Daresbury Lab, Warrington, Nuclear Physics Group, Cheshire (United Kingdom); Mahata, K. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Bhabha Atomic Research Centre, Nuclear Physics Division, Trombay (India); Paschalis, S. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); University of Liverpool, Department of Physics, Liverpool (United Kingdom); Savran, D. [Research Division GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Frankfurt Institute for Advanced Studies FIAS, Frankfurt am Main (Germany); Stroth, J. [Goethe Universitaet, Institut fuer Angewandte Physik, Frankfurt am Main (Germany); Wiescher, M. [University of Notre Dame, JINA, Notre Dame, IN (United States)
2015-01-01
Two-proton decay of the unbound T{sub z} =-2 nucleus {sup 16}Ne, produced in one-neutron knockout from a 500 MeV/u {sup 17}Ne beam, has been studied at GSI. The ground state, at a resonance energy 1.388(15) MeV, (Γ = 0.082(15) MeV) above the {sup 14}O+p+p threshold, and two narrow resonances at E{sub r} = 3.220(46) MeV and 7.57(6) MeV have been investigated. A comparison of the energy difference between the first excited 2{sup +} state and the 0{sup +} ground state in {sup 16}Ne with its mirror nucleus {sup 16}C reveals a small Thomas-Ehrman shift (TES) of +70(46) keV. A trend of the TES for the T = 2 quintet is obtained by completing the known data with a prediction for {sup 16}F obtained from an IMME analysis. The decay mechanisms of the observed three resonances were revealed from an analysis of the energy and angular correlations of the {sup 14}O+p+p decay products. The ground state decay can be considered as a genuine three-body (democratic) mode and the excited states decay sequentially via states in the intermediate nucleus {sup 15}F, the 3.22 MeV state predominantly via the {sup 15}F ground-state resonance, while the 7.57 MeV state decays via the 5/2{sup +} resonance in {sup 15}F at 2.8 MeV above the {sup 14}O+p+p threshold. Further, from an analysis of angular correlations, the spin-parity of the 7.57 MeV state has been determined as I{sup π} = 2{sup +} and assigned as the third 2{sup +} state in {sup 16}Ne based on a comparison with {sup 16}C. (orig.)
A microscopic approach to Casimir and Casimir–Polder forces between metallic bodies
International Nuclear Information System (INIS)
Barcellona, Pablo; Passante, Roberto
2015-01-01
We consider the Casimir–Polder interaction energy between a metallic nanoparticle and a metallic plate, as well as the Casimir interaction energy between two macroscopic metal plates, in terms of the many-body dispersion interactions between their constituents. Expressions for two- and three-body dispersion interactions between the microscopic parts of a real metal are first obtained, both in the retarded and non-retarded limits. These expressions are then used to evaluate the overall two- and three-body contributions to the macroscopic Casimir–Polder and Casimir force, and to compare them with each other, for the two following geometries: metal nanoparticle/half-space and half-space/half-space, where all the materials are assumed perfect conductors. The above evaluation is obtained by summing up the contributions from the microscopic constituents of the bodies (metal nanoparticles). In the case of nanoparticle/half-space, our results fully agree with those that can be extracted from the corresponding macroscopic results, and explicitly show the non-applicability of the pairwise approximation for the geometry considered. In both cases, we find that, while the overall two-body contribution yields an attractive force, the overall three-body contribution is repulsive. Also, they turn out to be of the same order, consistently with the known non applicability of the pairwise approximation. The issue of the rapidity of convergence of the many-body expansion is also briefly discussed
Physical Attractiveness and Courtship
Silverman, Irwin
1971-01-01
This study shows a high and disquieting degree of similarity in physical attractiveness between dating partners, and suggests also that more similar partners tend to form stronger romantic attachments. (Author)
Solution of the Chandler-Gibson equations for a three-body test problem
International Nuclear Information System (INIS)
Gibson, A.G.; Waters, A.J.; Berthold, G.H.; Chandler, C.
1991-01-01
The Chandler-Gibson (CG) N-body equations are tested by considering the problem of three nonrelativistic particles moving on a line and interacting through attractive delta-function potentials. In particular, the input Born and overlap matrix-valued functions are evaluated analytically, and the CG equations are solved using a B-spline collocation method. The computed scattering matrix elements are within 0.5% of the known exact solutions, and the corresponding scattering probabilities are within 0.001% of the exact probabilities, both below and above the 3-body breakup threshold. These results establish that the CG method is practical, as well as theoretically correct, and may be a valuable approach for solving certain more complicated N-body scattering problems
International Nuclear Information System (INIS)
Motovilov, A.K.
2005-01-01
We describe the basic structure of the two- and three-body T-matrices, scattering matrices, and resolvents continued to the unphysical energy sheets. The description is based on the explicit representations that have been found for analytically continued kernels of the T-operators. (author)
Ferrari, Fabio; Lavagna, Michèle
2018-06-01
The design of formations of spacecraft in a three-body environment represents one of the most promising challenges for future space missions. Two or more cooperating spacecraft can greatly answer some very complex mission goals, not achievable by a single spacecraft. The dynamical properties of a low acceleration environment such as the vicinity of libration points associated to a three-body system, can be effectively exploited to design spacecraft configurations able of satisfying tight relative position and velocity requirements. This work studies the evolution of an uncontrolled formation orbiting in the proximity of periodic orbits about collinear libration points under the Circular and Elliptic Restricted Three-Body Problems. A three spacecraft triangularly-shaped formation is assumed as a representative geometry to be investigated. The study identifies initial configurations that provide good performance in terms of formation keeping, and investigates key parameters that control the relative dynamics between the spacecraft within the three-body system. Formation keeping performance is quantified by monitoring shape and size changes of the triangular formation. The analysis has been performed under five degrees of freedom to define the geometry, the orientation and the location of the triangle in the synodic rotating frame.
Stability at Potential Maxima: The L-4 and L-5 Points of the Restricted Three-Body Problem.
Greenberg, Richard; Davis, Donald R.
1978-01-01
Describes a dynamical system which is stable at potential maxima. The maxima, called L-4 and L-5, are stable locations of the restricted three-body problem. Energy loss from the system will tend to drive it away from stability. (GA)
International Nuclear Information System (INIS)
Melde, T.; Canton, L.; Svenne, J.P.
2002-01-01
We formulate the three-body problem in one dimension in terms of the (Faddeev-type) integral equation approach. As an application, we develop a spinless, one-dimensional (1-D) model that mimics three-nucleon dynamics in one dimension. Using simple two-body potentials that reproduce the deuteron binding, we obtain that the three-body system binds at about 7.5 MeV. We then consider two types of residual pionic corrections in the dynamical equation; one related to the 2π-exchange three-body diagram, the other to the 1π-exchange three-body diagram. We find that the first contribution can produce an additional binding effect of about 0.9 MeV. The second term produces smaller binding effects, which are, however, dependent on the uncertainty in the off-shell extrapolation of the two-body t-matrix. This presents interesting analogies with what occurs in three dimensions. The paper also discusses the general three-particle quantum scattering problem, for motion restricted to the fall line. (author)
Method of resonating groups in the Faddeev-Hahn equation formalism for three-body nuclear problem
Nasirov, M Z
2002-01-01
The Faddeev-Hahn equation formalism for three-body nuclear problem is considered. For solution of the equations the method of resonant groups have applied. The calculations of tritium binding energy and doublet nd-scattering length have been carried out. The results obtained shows that Faddeev-Hahn equation formalism is very simple and effective. (author)
Hyperspherical functions and quantum-mechanical three-body problem with application to carbon 12
International Nuclear Information System (INIS)
Letz, H.
1975-01-01
In this work a system of three identical particles (bosons) interacting by a particular two-body force is discussed. Using the complete set of the hyperspherical functions (K-harmonics), analytical expressions for eigenvalues and wave functions of the stationary states are found. The numerical evaluation gives a level sequence for a definite pair of potential parameters similar to that of the nucleus carbon 12
Analysis tools for precision studies of hadronic three-body decays and transition form factors
International Nuclear Information System (INIS)
Schneider, Sebastian Philipp
2013-01-01
Due to the running coupling constant of Quantum Chromodynamics one of the pillars of the Standard Model, the strong interactions, is still insufficiently understood at low energies. In order to describe the interactions of hadrons that form in this physical regime, one has to devise methods that are non-perturbative in the strong coupling constant. In particular hadronic three-body decays and transition form factors present a great challenge due to the complex analytic structure ensued by strong final-state interactions. In this thesis we present two approaches to tackle these processes. In the first part we use a modified version of non-relativistic effective field theory to analyze the decay η→3π. This perturbative low-energy expansion is ideally suited to study the effects of ππ rescattering and contributes greatly to the understanding of the slope parameter of the η→3π 0 Dalitz plot, a quantity that is strongly influenced by final-state interactions and has presented a long-standing puzzle for theoretical approaches. In the second part we present dispersion relations as a non-perturbative means to study three-particle decays. Using the example of η'→ηππ we give a detailed introduction to the framework and its numerical implementation. We confront our findings with recent experimental data from the BES-III and VES collaborations and discuss whether the extraction of πη scattering parameters, one of the prime motives to study this decay channel, is feasible in such an approach. A more clear-cut application is given in our study of the decays ω/φ→3π due to the relative simplicity of this decay channel: our results are solely dependent on the ππ P-wave scattering phase shift. We give predictions for the Dalitz plot distributions and compare our findings to very precise data on φ→3π by the KLOE and CMD-2 collaborations. We also predict Dalitz plot parameters that may be determined in future high-precision measurements of ω→3π and
Analysis tools for precision studies of hadronic three-body decays and transition form factors
Energy Technology Data Exchange (ETDEWEB)
Schneider, Sebastian Philipp
2013-02-14
Due to the running coupling constant of Quantum Chromodynamics one of the pillars of the Standard Model, the strong interactions, is still insufficiently understood at low energies. In order to describe the interactions of hadrons that form in this physical regime, one has to devise methods that are non-perturbative in the strong coupling constant. In particular hadronic three-body decays and transition form factors present a great challenge due to the complex analytic structure ensued by strong final-state interactions. In this thesis we present two approaches to tackle these processes. In the first part we use a modified version of non-relativistic effective field theory to analyze the decay {eta}{yields}3{pi}. This perturbative low-energy expansion is ideally suited to study the effects of {pi}{pi} rescattering and contributes greatly to the understanding of the slope parameter of the {eta}{yields}3{pi}{sup 0} Dalitz plot, a quantity that is strongly influenced by final-state interactions and has presented a long-standing puzzle for theoretical approaches. In the second part we present dispersion relations as a non-perturbative means to study three-particle decays. Using the example of {eta}'{yields}{eta}{pi}{pi} we give a detailed introduction to the framework and its numerical implementation. We confront our findings with recent experimental data from the BES-III and VES collaborations and discuss whether the extraction of {pi}{eta} scattering parameters, one of the prime motives to study this decay channel, is feasible in such an approach. A more clear-cut application is given in our study of the decays {omega}/{phi}{yields}3{pi} due to the relative simplicity of this decay channel: our results are solely dependent on the {pi}{pi} P-wave scattering phase shift. We give predictions for the Dalitz plot distributions and compare our findings to very precise data on {phi}{yields}3{pi} by the KLOE and CMD-2 collaborations. We also predict Dalitz plot
Attracting International Hotels
DEFF Research Database (Denmark)
Assaf, A. George; Josiassen, Alexander; Agbola, Frank Wogbe
2015-01-01
With the increased international competition facing hotel chains, it is essential that the next destination they enter is the most attractive option possible. The host destinations too have a keen interest in strategically positioning themselves in order to attract international hotels since...... their presence has several positive effects. Using, for the first time, actual on-location data we investigate the factors that matter most for international hotels when selecting host destinations. Specifically, we identify 23 factors that make a destination an attractive (or unattractive) location...... for international hotels. We then rank these. The results show that welcomeness, infrastructure, and crime rate are the three most important factors that influence the location of international hotels in host destinations....
Borg, Anne; Sui, Manling
2013-03-01
Large regional differences remain in the number of girls studying physics and the number of female physicists in academic positions. While many countries struggle with attracting female students to university studies in physics, climbing the academic ladder is the main challenge for these women. Furthermore, for many female physicists the working climate is not very supportive. The workshop Attracting Girls to Physics, organized as part of the 4th IUPAP International Conference on Women in Physics, South Africa 2011, addressed attitudes among education-seeking teenagers and approaches for attracting young girls to physics through successful recruitment plans, including highlighting the broad spectrum of career opportunities for those with physics qualifications. The current paper presents findings, examples of best practices, and recommendations resulting from this workshop.
Clusters in attractive colloids
Energy Technology Data Exchange (ETDEWEB)
Coniglio, A [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' , Complesso Universitario di Monte Sant' Angelo, via Cintia 80126 Naples (Italy); Arcangelis, L de [Dipartimento di Ingegneria dell' Informazione and CNISM II Universita di Napoli, Aversa (CE) (Italy); Candia, A de [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' , Complesso Universitario di Monte Sant' Angelo, via Cintia 80126 Naples (Italy); Gado, E Del [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' , Complesso Universitario di Monte Sant' Angelo, via Cintia 80126 Naples (Italy); Fierro, A [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' , Complesso Universitario di Monte Sant' Angelo, via Cintia 80126 Naples (Italy); Sator, N [Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie-Paris6, UMR (CNRS) 7600 Case 121, 4 Place Jussieu 75252 Paris Cedex 05 (France)
2006-09-13
We discuss how the anomalous increase of the viscosity in colloidal systems with short-range attraction can be related to the formation of long-living clusters. Based on molecular dynamics and Monte Carlo numerical simulations of different models, we propose a similar picture for colloidal gelation at low and intermediate volume fractions. On this basis, we analyze the distinct role played by the formation of long-living bonds and the crowding of the particles in the slow dynamics of attractive colloidal systems.
Radial Motion of Two Mutually Attracting Particles
Mungan, Carl E.
2009-01-01
A pair of masses or opposite-sign charges released from rest will move directly toward each other under the action of the inverse-distance-squared force of attraction between them. An exact expression for the separation distance as a function of time can only be found by numerically inverting the solution of a differential equation. A simpler,…
New approach to the theory of coupled πNN-NN system. III. A three-body limit
International Nuclear Information System (INIS)
Avishai, Y.; Mizutani, T.
1980-01-01
In the limit where the pion is restricted to be emitted only by the nucleon that first absorbed it, it is shown that the equations previously developed to describe the couple πNN (πd) - NN system reduce to conventional three-body equations. Specifically, it is found in this limit that the input πN p 11 amplitude which, put on-shell, is directly related to the experimental phase shift, contrary to the original equations where the direct (dressed) nucleon pole term and the non-pole part of this partial wave enter separately. The present study clarifies the limitation of pure three-body approach to the πNN-NN problems as well as suggests a rare opportunity of observing a possible resonance behavior in the non-pole part of the πN P 11 amplitude through πd experiments
International Nuclear Information System (INIS)
Chen Yan; Chen Yong; Zhang Kezhi
2009-01-01
We study the dynamic behaviour of Bose-Einstein condensates with two- and three-atom interactions in optical lattices with analytical and numerical methods. It is found that the steady-state relative population displays tuning-fork bifurcation when the system parameters are changed to certain critical values. In particular, the existence of the three-body interaction not only transforms the bifurcation point of the system but also greatly affects the macroscopic quantum self-trapping behaviours associated with the critically stable steady-state solution. In addition, we investigated the influence of the initial conditions, three-body interaction, and the energy bias on the macroscopic quantum self-trapping. Finally, by applying the periodic modulation on the energy bias, we observed that the relative population oscillation exhibits a process from order to chaos, via a series of period-doubling bifurcations.
What are the advantages of a three body model with core excitation for 21Ne and 21Na?
International Nuclear Information System (INIS)
Nunes, F.M.; Thompson, I.J.
2004-01-01
21 Ne and 21 Na are well bound nuclei and there is a large amount of data available up to considerable excitation energy, and this imposes a severe test on the structure models. Preliminary results for the structure of these nuclei based on three body models ( 21 Ne= 16 O+α+n and 21 Na= 16 O+α+p) are presented. Three-body calculations without core excitation produce the positive parity states in fair agreement with experiment, while slightly overbinding the systems. As expected, these models fail to reproduce the low lying negative parity states, which are predicted by shell model to have mainly core excited configurations. As a first step we have included the 3 - state of 16 O in our model. Convergence issues will be discussed. Results suggest that more excited states may be required to describe the system
International Nuclear Information System (INIS)
D'Angelo, P.; Pavel, N.V.
1999-01-01
The solvation structure of Sr 2+ ions in acetonitrile has been studied by x-ray absorption spectroscopy (XAS) and molecular dynamics (MD) simulations. The extended x-ray absorption fine structure (EXAFS) above the Sr K-edge has been interpreted in the framework of the multiple scattering (MS) formalism and, for the first time, clear evidence of MS contributions has been found for non-complexing ions in solution. Molecular dynamics has been used to generate the partial pair g(r) and the three-body g(r 1 , r 2 , θ) distribution functions from which a model χ(k) has been constructed. An excellent agreement has been found between the theoretical and experimental data. This result demonstrates the ability of the XAS technique in probing three-body correlation functions in solutions. (au)
Three-body recombination of two-component cold atomic gases into deep dimers in an optical model
DEFF Research Database (Denmark)
Mikkelsen, Mathias; Jensen, A. S.; Fedorov, D. V.
2015-01-01
to the decay rate or recombination probability of the three-body system. The method is formulated in details and the relevant qualitative features are discussed as functions of scattering lengths and masses. We use zero-range model in analyses of recent recombination data. The dominating scattering length......We consider three-body recombination into deep dimers in a mass-imbalanced two-component atomic gas. We use an optical model where a phenomenological imaginary potential is added to the lowest adiabatic hyper-spherical potential. The consequent imaginary part of the energy eigenvalue corresponds...... is usually related to the non-equal two-body systems. We account for temperature smearing which tends to wipe out the higher-lying Efimov peaks. The range and the strength of the imaginary potential determine positions and shapes of the Efimov peaks as well as the absolute value of the recombination rate...
INVESTMENT ATTRACTIVENESS OF ENTERPRISES
Directory of Open Access Journals (Sweden)
Nadiia Davydenko
2017-03-01
Full Text Available In the article the approaches to defining the essence of the concept of “investment attractiveness of enterprises” were analyzed. On the example of "Agrofirm Brusilov" depth analysis of the agricultural enterprises to evaluate of profitability, liquidity, solvency, financial stability, the timing of the return of invested funds and minimizing investment risks was conducted. To study methods of rating and system analysis were used. To justify the conditions of increasing investment attractiveness farms method of scoring was used. It was established as a result of the use of integrated evaluation of the financial position one can see problem aspects of financial position of the company and develop measures to enhance liquidity, solvency, identify potential for raising the efficiency of company and prevention of financial crisis. The analysis of financial position showed that the management of the enterprise doesn’t think about financial stability and solvency, does not understand the benefit of borrowed capital. Using research results in practice of agricultural enterprises allows us to give a real evaluation of investment attractiveness and justify ways to improve it. Key words: investments, investment attractiveness, potential business, financial position.
Directory of Open Access Journals (Sweden)
A. Narayan
2013-01-01
Full Text Available The oblateness and the photogravitational effects of both the primaries on the location and the stability of the triangular equilibrium points in the elliptical restricted three-body problem have been discussed. The stability of the triangular points under the photogravitational and oblateness effects of both the primaries around the binary systems Achird, Lyeten, Alpha Cen-AB, Kruger 60, and Xi-Bootis, has been studied using simulation techniques by drawing different curves of zero velocity.
International Nuclear Information System (INIS)
Petrov, N.M.; Pushkash, A.M.
1985-01-01
In accordance with the main idea of the phase function method the two-body off-shell scattering amplitudes are considered as the limit of the scattering amplitude sequence corresponding to the sequence of the R-radius cut-off potentials. The explicit analytical expression for the scattering amplitudes function is obtained in the case of separable potentials, due to which the three-body problem is investigated
Solar sail trajectory design in the Earth-Moon circular restricted three body problem
Das, Ashwati
The quest to explore the Moon has helped resolve scientific questions, has spurred leaps in technology development, and has revealed Earth's celestial companion to be a gateway to other destinations. With a renewed focus on returning to the Moon in this decade, alternatives to chemical propulsion systems are becoming attractive methods to efficiently use scarce resources and support extended mission durations. Thus, an investigation is conducted to develop a general framework, that facilitates propellant-free Earth-Moon transfers by exploiting sail dynamics in combination with advantageous transfer options offered in the Earth-Moon circular restricted multi-body dynamical model. Both periodic orbits in the vicinity of the Earth-Moon libration points, and lunar-centric long-term capture orbits are incorporated as target destinations to demonstrate the applicability of the general framework to varied design scanarios, each incorporating a variety of complexities and challenges. The transfers are comprised of three phases - a spiral Earth escape, a transit period, and, finally, the capture into a desirable orbit in the vicinity of the Moon. The Earth-escape phase consists of spiral trajectories constructed using three different sail steering strategies - locally optimal, on/off and velocity tangent. In the case of the Earth-libration point transfers, naturally occurring flow structures (e.g., invariant manifolds) arising from the mutual gravitational interaction of the Earth and Moon are exploited to link an Earth departure spiral with a destination orbit. In contrast, sail steering alone is employed to establish a link between the Earth-escape phase and capture orbits about the Moon due to a lack of applicable natural structures for the required connection. Metrics associated with the transfers including flight-time and the influence of operational constraints, such as occultation events, are investigated to determine the available capabilities for Earth
Conformation-dependent DNA attraction
Li, Weifeng; Nordenskiöld, Lars; Zhou, Ruhong; Mu, Yuguang
2014-05-01
Understanding how DNA molecules interact with other biomolecules is related to how they utilize their functions and is therefore critical for understanding their structure-function relationships. For a long time, the existence of Z-form DNA (a left-handed double helical version of DNA, instead of the common right-handed B-form) has puzzled the scientists, and the definitive biological significance of Z-DNA has not yet been clarified. In this study, the effects of DNA conformation in DNA-DNA interactions are explored by molecular dynamics simulations. Using umbrella sampling, we find that for both B- and Z-form DNA, surrounding Mg2+ ions always exert themselves to screen the Coulomb repulsion between DNA phosphates, resulting in very weak attractive force. On the contrary, a tight and stable bound state is discovered for Z-DNA in the presence of Mg2+ or Na+, benefiting from their hydrophobic nature. Based on the contact surface and a dewetting process analysis, a two-stage binding process of Z-DNA is outlined: two Z-DNA first attract each other through charge screening and Mg2+ bridges to phosphate groups in the same way as that of B-DNA, after which hydrophobic contacts of the deoxyribose groups are formed via a dewetting effect, resulting in stable attraction between two Z-DNA molecules. The highlighted hydrophobic nature of Z-DNA interaction from the current study may help to understand the biological functions of Z-DNA in gene transcription.Understanding how DNA molecules interact with other biomolecules is related to how they utilize their functions and is therefore critical for understanding their structure-function relationships. For a long time, the existence of Z-form DNA (a left-handed double helical version of DNA, instead of the common right-handed B-form) has puzzled the scientists, and the definitive biological significance of Z-DNA has not yet been clarified. In this study, the effects of DNA conformation in DNA-DNA interactions are explored by
A system of tourism attractions
Kušen, Eduard
2010-01-01
Although tourism attractions are a basic resource for long term tourism developments, they are not given the proper attention, both, theoretical and practical. Therefore, rare studies of tourism attractions, especially those with the ambition of creating a functional system of tourism attractions, attract special attention. The aim of this paper is to present a new system of tourism attractions. This new system is based on the review of published research on tourism attractions, particularly ...
Conformation-dependent DNA attraction.
Li, Weifeng; Nordenskiöld, Lars; Zhou, Ruhong; Mu, Yuguang
2014-06-21
Understanding how DNA molecules interact with other biomolecules is related to how they utilize their functions and is therefore critical for understanding their structure-function relationships. For a long time, the existence of Z-form DNA (a left-handed double helical version of DNA, instead of the common right-handed B-form) has puzzled the scientists, and the definitive biological significance of Z-DNA has not yet been clarified. In this study, the effects of DNA conformation in DNA-DNA interactions are explored by molecular dynamics simulations. Using umbrella sampling, we find that for both B- and Z-form DNA, surrounding Mg(2+) ions always exert themselves to screen the Coulomb repulsion between DNA phosphates, resulting in very weak attractive force. On the contrary, a tight and stable bound state is discovered for Z-DNA in the presence of Mg(2+) or Na(+), benefiting from their hydrophobic nature. Based on the contact surface and a dewetting process analysis, a two-stage binding process of Z-DNA is outlined: two Z-DNA first attract each other through charge screening and Mg(2+) bridges to phosphate groups in the same way as that of B-DNA, after which hydrophobic contacts of the deoxyribose groups are formed via a dewetting effect, resulting in stable attraction between two Z-DNA molecules. The highlighted hydrophobic nature of Z-DNA interaction from the current study may help to understand the biological functions of Z-DNA in gene transcription.
Frolov, Alexei M.
2018-03-01
The universal variational expansion for the non-relativistic three-body systems is explicitly constructed. This universal expansion can be used to perform highly accurate numerical computations of the bound state spectra in various three-body systems, including Coulomb three-body systems with arbitrary particle masses and electric charges. Our main interest is related to the adiabatic three-body systems which contain one bound electron and two heavy nuclei of hydrogen isotopes: the protium p, deuterium d and tritium t. We also consider the analogous (model) hydrogen ion ∞H2+ with the two infinitely heavy nuclei.
Timetable Attractiveness Parameters
DEFF Research Database (Denmark)
Schittenhelm, Bernd
2008-01-01
Timetable attractiveness is influenced by a set of key parameters that are described in this article. Regarding the superior structure of the timetable, the trend in Europe goes towards periodic regular interval timetables. Regular departures and focus on optimal transfer possibilities make...... these timetables attractive. The travel time in the timetable depends on the characteristics of the infrastructure and rolling stock, the heterogeneity of the planned train traffic and the necessary number of transfers on the passenger’s journey. Planned interdependencies between trains, such as transfers...... and heterogeneous traffic, add complexity to the timetable. The risk of spreading initial delays to other trains and parts of the network increases with the level of timetable complexity....
Sharing Rare Attitudes Attracts.
Alves, Hans
2018-04-01
People like others who share their attitudes. Online dating platforms as well as other social media platforms regularly rely on the social bonding power of their users' shared attitudes. However, little is known about moderating variables. In the present work, I argue that sharing rare compared with sharing common attitudes should evoke stronger interpersonal attraction among people. In five studies, I tested this prediction for the case of shared interests from different domains. I found converging evidence that people's rare compared with their common interests are especially potent to elicit interpersonal attraction. I discuss the current framework's theoretical implications for impression formation and impression management as well as its practical implications for improving online dating services.
Antipsychotics and physical attractiveness.
Seeman, Mary V
2011-10-01
Antipsychotics are effective in treating the symptoms of schizophrenia, but they may induce adverse effects, some of which-those that impact negatively on physical appearance-have not been sufficiently discussed in the psychiatric literature. Through a narrative review, to catalog antipsychotic side effects that interfere with physical attractiveness and to suggest ways of addressing them. PubMed databases were searched for information on the association between "antipsychotic side effects" and "attractiveness" using those two search phrases plus the following terms: "weight," "teeth," "skin," "hair," "eyes," "gait," "voice," "odor." Data from relevant qualitative and quantitative articles were considered, contextualized, and summarized. Antipsychotics, as a group, increase weight and may lead to dry mouth and bad breath, cataracts, hirsutism, acne, and voice changes; they may disturb symmetry of gait and heighten the risk for tics and spasms and incontinence, potentially undermining a person's attractiveness. Clinicians need to be aware of the impact of therapeutic drugs on appearance and how important this issue is to patients. Early in treatment, they need to plan preventive and therapeutic strategies.
Electronic circuit for control rod attracting electromagnet
International Nuclear Information System (INIS)
Ito, Koji.
1991-01-01
The present invention provides a discharging circuit for control rod attracting electromagnet used for a reactor which is highly reliable and has high performance. The resistor of the circuit comprises a non-linear resistor element and a blocking rectification element connected in series. The discharging circuit can be prevented from short-circuit by selecting a resistor having a resistance value about ten times as great as the coil resistance, even in a case where the blocking rectification element and the non-linear resistor element are failed. Accordingly, reduction of attracting force and the increase of scream releasing time can be minimized. (I.S.)
Benson, Christopher R; Maffeo, Christopher; Fatila, Elisabeth M; Liu, Yun; Sheetz, Edward G; Aksimentiev, Aleksei; Singharoy, Abhishek; Flood, Amar H
2018-05-07
The coordinated motion of many individual components underpins the operation of all machines. However, despite generations of experience in engineering, understanding the motion of three or more coupled components remains a challenge, known since the time of Newton as the "three-body problem." Here, we describe, quantify, and simulate a molecular three-body problem of threading two molecular rings onto a linear molecular thread. Specifically, we use voltage-triggered reduction of a tetrazine-based thread to capture two cyanostar macrocycles and form a [3]pseudorotaxane product. As a consequence of the noncovalent coupling between the cyanostar rings, we find the threading occurs by an unexpected and rare inchworm-like motion where one ring follows the other. The mechanism was derived from controls, analysis of cyclic voltammetry (CV) traces, and Brownian dynamics simulations. CVs from two noncovalently interacting rings match that of two covalently linked rings designed to thread via the inchworm pathway, and they deviate considerably from the CV of a macrocycle designed to thread via a stepwise pathway. Time-dependent electrochemistry provides estimates of rate constants for threading. Experimentally derived parameters (energy wells, barriers, diffusion coefficients) helped determine likely pathways of motion with rate-kinetics and Brownian dynamics simulations. Simulations verified intercomponent coupling could be separated into ring-thread interactions for kinetics, and ring-ring interactions for thermodynamics to reduce the three-body problem to a two-body one. Our findings provide a basis for high-throughput design of molecular machinery with multiple components undergoing coupled motion.
Directory of Open Access Journals (Sweden)
Horng-Wen Wu
2017-10-01
Full Text Available Recently, many studies have investigated the friction, wear, and temperature characteristics of the interface between two relative movements. Such analyses often set the coefficient of friction as a fixed value and are analyzed in cases of two-body contact; however, the interface is often a three-body contact and the coefficient of friction varies depending on the operating conditions. This is a significant error in the analysis of contact characteristics, therefore, in this study, the actual interface and the change of the coefficient of friction were analyzed based on three-body micro-contact theory where the contact temperature was also analyzed and the difference between the generally assumed values were compared. The results showed that under three-body contact, the coefficient of total friction increased with an increase in particle size; and at a different particle size and area density of particles, the surface contact temperature increased with the plasticity index and load increases, and the particle contact temperature increased with the increasing particle size. The surface temperature rise was mainly affected by the ratio of the average temperature between surface 1 and surface 2 to the multiplication between the 100th root of the area density of particles and the square root of the equivalent surface roughness (Ts1s2_ave*/ηa0.01σ0.5 and the ratio of the 10th root of the mean particle diameter to the 100th root of the equivalent surface roughness (xa0.1/σ0.001. Particle temperature was mainly affected by the ratio of the 10th root of the mean particle diameter to the 100th root of the equivalent surface roughness (xa0.1/σ0.001 and the area density of particles ηa. Our study indicated that when the contact of surface with surface and the contact of the particles with the surface, the resulting heat balance was assigned to the particles and the surface in a three-body contact situation. Under this contact behavior, it could avoid
International Nuclear Information System (INIS)
Bray, I.; Stelbovics, A.T.
1992-01-01
Convergence as a function of the number of states is studied and demonstrated for the Poet-Temkin model of electron-hydrogen scattering. In this Coulomb three-body problem only the l=0 partial waves are treated. By taking as many as thirty target states, obtained by diagonalizing the target Hamiltonian in a Laguerre basis, complete agreement with the smooth results of Poet is obtained at all energies. We show that the often-encountered pseudoresonance features in the cross sections are simply an indication of an inadequate target state representation
International Nuclear Information System (INIS)
Cardoso, W. B.; Avelar, A. T.; Bazeia, D.
2011-01-01
We deal with the three-dimensional Gross-Pitaevskii equation which is used to describe a cloud of dilute bosonic atoms that interact under competing two- and three-body scattering potentials. We study the case where the cloud of atoms is strongly confined in two spatial dimensions, allowing us to build an unidimensional nonlinear equation,controlled by the nonlinearities and the confining potentials that trap the system along the longitudinal coordinate. We focus attention on specific limits dictated by the cubic and quintic coefficients, and we implement numerical simulations to help us to quantify the validity of the procedure.
Threshold separation distance for attractive interaction between dust particles
International Nuclear Information System (INIS)
Jabdaraghi, R. Najafi; Sobhanian, S.
2008-01-01
Interaction between dust grains in a dusty plasma could be both repulsive and attractive. The Coulomb interaction between two negatively charged dust particulates and the electrostatic force between them are repulsive, while the shadowing force affecting them is attractive. We show in this paper that in some experimental conditions, there is some grain separation zone for which the attractive shadowing force is larger than the repulsive forces between them. In experimental conditions, for the grains separation distance r = 0.4 cm the shadowing force is almost equal to the electrostatic force between them and for r>0.4 cm the shadowing force exceeds the electrostatic force. So the resultant interaction force will be attractive. The possibility of dust crystal formation in this zone and also the motion of dust particles in the resultant potential of the form V = -(a/r)+(b/r 2 ) will be discussed. This form of potential comes from the combination electrostatic (F es (c/r 3 )) and shadowing (F shadow = -(d/r 2 )) forces.
Three-body and four-body photodisintegrations of the 4He nuclei in the Δ region
International Nuclear Information System (INIS)
Niki, Kazuaki
1991-01-01
The differential and total cross sections were measured for the three-body (pnd) and four-body (ppnn) final states in photodisintegration of 4 He in an energy range between 125 and 445 MeV. The kinematic variables were determined in an almost complete way, using a large acceptance spectrometer together with the use of tagged photons of an energy resolution of 10 MeV. We have found that the three-body reaction 4 He(γ, pn)d makes a dominant contribution among various processes which lead to non-mesonic final states. The behavior of the 4 He(γ, pn)d cross section is well described by the quasi-deuteron model (QDM). On the other hand, the four-body breakup cross sections are not consistent with the prediction of the QDM. For these four-body reactions, photon absorption by three-nucleon clusters seems to give a dominant effect. The four-body cross sections also show a broad enhancement around 300 to 400 MeV, indicating a possible participation of the Δ to the reactions. (author)
Energy Technology Data Exchange (ETDEWEB)
Proynov, Emil; Wang, Matthew; Kong, Jing, E-mail: jing.kong@mtsu.edu [Department of Chemistry and Center for Computational Sciences, Middle Tennessee State University, Murfreesboro, Tennessee 37132 (United States); Liu, Fenglai [Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York 14260 (United States); Gan, Zhengting [Q-Chem Inc., 5001 Baum Boulevard, Pittsburgh, Pennsylvania 15213 (United States)
2015-08-28
We implement and compute the density functional nonadditive three-body dispersion interaction using a combination of Tang-Karplus formalism and the exchange-dipole moment model of Becke and Johnson. The computation of the C{sub 9} dispersion coefficients is done in a non-empirical fashion. The obtained C{sub 9} values of a series of noble atom triplets agree well with highly accurate values in the literature. We also calculate the C{sub 9} values for a series of benzene trimers and find a good agreement with high-level ab initio values reported recently in the literature. For the question of damping of the three-body dispersion at short distances, we propose two damping schemes and optimize them based on the benzene trimers data, and the fitted analytic potentials of He{sub 3} and Ar{sub 3} trimers fitted to the results of high-level wavefunction theories available from the literature. Both damping schemes respond well to the optimization of two parameters.
Three-body recombination of two-component cold atomic gases into deep dimers in an optical model
International Nuclear Information System (INIS)
Mikkelsen, M; Jensen, A S; Fedorov, D V; Zinner, N T
2015-01-01
We consider three-body recombination into deep dimers in a mass-imbalanced two-component atomic gas. We use an optical model where a phenomenological imaginary potential is added to the lowest adiabatic hyper-spherical potential. The consequent imaginary part of the energy eigenvalue corresponds to the decay rate or recombination probability of the three-body system. The method is formulated in details and the relevant qualitative features are discussed as functions of scattering lengths and masses. We use zero-range model in analyses of recent recombination data. The dominating scattering length is usually related to the non-equal two-body systems. We account for temperature smearing which tends to wipe out the higher-lying Efimov peaks. The range and the strength of the imaginary potential determine positions and shapes of the Efimov peaks as well as the absolute value of the recombination rate. The Efimov scaling between recombination peaks is calculated and shown to depend on both scattering lengths. Recombination is predicted to be largest for heavy–heavy–light systems. Universal properties of the optical parameters are indicated. We compare to available experiments and find in general very satisfactory agreement. (paper)
Directory of Open Access Journals (Sweden)
Takashi Ito
2016-01-01
Full Text Available Terms in the analytic expansion of the doubly averaged disturbing function for the circular restricted three-body problem using the Legendre polynomial are explicitly calculated up to the fourteenth order of semimajor axis ratio (α between perturbed and perturbing bodies in the inner case (α1. The expansion outcome is compared with results from numerical quadrature on an equipotential surface. Comparison with direct numerical integration of equations of motion is also presented. Overall, the high-order analytic expansion of the doubly averaged disturbing function yields a result that agrees well with the numerical quadrature and with the numerical integration. Local extremums of the doubly averaged disturbing function are quantitatively reproduced by the high-order analytic expansion even when α is large. Although the analytic expansion is not applicable in some circumstances such as when orbits of perturbed and perturbing bodies cross or when strong mean motion resonance is at work, our expansion result will be useful for analytically understanding the long-term dynamical behavior of perturbed bodies in circular restricted three-body systems.
Attraction of semiconductor nanowires: An in situ observation
International Nuclear Information System (INIS)
Chen, Bin; Gao, Qiang; Chang, Li; Wang, Yanbo; Chen, Zibin; Liao, Xiaozhou; Tan, Hark Hoe; Zou, Jin; Ringer, Simon P.; Jagadish, Chennupati
2013-01-01
Graphical abstract: -- Abstract: In situ deformation transmission electron microscopy was used to study the attraction behavior of GaAs semiconductor nanowires (NWs). The NWs demonstrated an interesting phenomenon of either head-to-head or body-to-body attraction at distances that depend on the NW diameters. The NWs with a diameter of ∼25 nm attracted at a distance of ∼25 nm, while large-diameter NWs of ∼55 nm showed no obvious attraction. The underlying mechanism governing the attraction of the NWs is proposed and discussed with a mechanistic model. The diameter dependence on the NW attraction behavior is discussed. The finding provides an understanding of the Ampère force in nanostructured materials caused by an electron-beam-induced current while technologically it provides useful hints for designing NW-based devices according to the diameter-dependent attraction behavior of NWs
Small Island Visitor Attractions
Directory of Open Access Journals (Sweden)
Haven Allahar
2015-03-01
Full Text Available This article proposes a process framework for developing and managing visitor attractions (VA in small island developing states with Trinidad and Tobago, a two-island state in the Caribbean, as the case study. An extensive literature review was conducted, supported by field observations, individual depth interviews, and small and large focus group meetings. The process framework identified four sets of processes: national policy formulation and legislation; inventory, classification, evaluation, and ranking of VA; general operations management involving project management activities; and site specific activities of development, operations, and maintenance. The value of the framework lies in the fact that no similar framework applicable to small islands was covered in the literature and validation was obtained from a panel of experts and a cross section of tourism stakeholders in Tobago.
On the cosmic-ray spectra of three-body lepton-flavor-violating dark matter decays
International Nuclear Information System (INIS)
Carone, Christopher D.; Cukierman, Ari; Primulando, Reinard
2011-01-01
We consider possible leptonic three-body decays of spin-1/2, charge-asymmetric dark matter. Assuming a general Dirac structure for the four-fermion contact interactions of interest, we study the cosmic-ray electron and positron spectra and show that good fits to the current data can be obtained for both charged-lepton-flavor-conserving and flavor-violating decay channels. We find that different choices for the Dirac structure of the underlying decay operator can be significantly compensated by different choices for the dark matter mass and lifetime. The decay modes we consider provide differing predictions for the cosmic-ray positron fraction at energies higher than those currently probed at the PAMELA experiment; these predictions might be tested at cosmic-ray detectors like AMS-02.
Energy Technology Data Exchange (ETDEWEB)
Mishra, Kalanand; /Nehru U.
2008-02-22
The authors present measurements of the relative branching ratios, Dalitz plot structures and CP-asymmetry values in the three-body singly Cabibbo-suppressed decays D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} and D{sup 0} {yields} K{sup -}K{sup +}{pi}{sup 0} using data collected by the BABAR detector at the PEP-II asymmetric-energy ring at SLAC. The author applies the results of the D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} analysis to extracting CP-violation parameters related to the CKM angle {gamma} (or {phi}{sub 3}) using the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup -}.
Three-body decays of Higgs bosons at LEP2 and application to a hidden fermiophobic Higgs
International Nuclear Information System (INIS)
Akeroyd, A.G.
1999-01-01
We study the decays of Higgs bosons to a lighter Higgs boson and a virtual gauge boson in the context of the non-supersymmetric two-Higgs doublet model (2HDM). We consider the phenomenological impact at LEP2 and find that such decays, when open, may be dominant in regions of parameter space and thus affect current Higgs boson search techniques. Three-body decays would be a way of producing light neutral Higgs bosons which have so far escaped detection at LEP due to suppressed couplings to the Z, and are of particular importance in the 2HDM (Model I) which allows both a light fermiophobic Higgs and a light charged scalar
Directory of Open Access Journals (Sweden)
Jagadish Singh
2012-01-01
Full Text Available This paper investigates the positions and linear stability of an infinitesimal body around the equilibrium points in the framework of the Robe’s circular restricted three-body problem, with assumptions that the hydrostatic equilibrium figure of the first primary is an oblate spheroid and the second primary is an oblate body as well. It is found that equilibrium point exists near the centre of the first primary. Further, there can be one more equilibrium point on the line joining the centers of both primaries. Points on the circle within the first primary are also equilibrium points under certain conditions and the existence of two out-of-plane points is also observed. The linear stability of this configuration is examined and it is found that points near the center of the first primary are conditionally stable, while the circular and out of plane equilibrium points are unstable.
Czech Academy of Sciences Publication Activity Database
Morgado, C.A.; Jurečka, P.; Svozil, Daniel; Hobza, Pavel; Šponer, Jiří
2009-01-01
Roč. 5, č. 6 (2009), s. 1524-1544 ISSN 1549-9618 R&D Projects: GA AV ČR(CZ) IAA400040802; GA AV ČR(CZ) IAA400550701; GA MŠk(CZ) LC06030 Grant - others:GA ČR(CZ) GA203/09/1476 Program:GA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702; CEZ:AV0Z40550506 Keywords : quantum chemical calculations * nucleic acids * force field Subject RIV: BO - Biophysics Impact factor: 4.804, year: 2009
Simulation of shear thickening in attractive colloidal suspensions.
Pednekar, Sidhant; Chun, Jaehun; Morris, Jeffrey F
2017-03-01
The influence of attractive forces between particles under conditions of large particle volume fraction, ϕ, is addressed using numerical simulations which account for hydrodynamic, Brownian, conservative and frictional contact forces. The focus is on conditions for which a significant increase in the apparent viscosity at small shear rates, and possibly the development of a yield stress, is observed. The high shear rate behavior for Brownian suspensions has been shown in recent work [R. Mari, R. Seto, J. F. Morris and M. M. Denn PNAS, 2015, 112, 15326-15330] to be captured by the inclusion of pairwise forces of two forms, one a contact frictional interaction and the second a repulsive force often found in stabilized colloidal dispersions. Under such conditions, shear thickening is observed when shear stress is comparable to the sum of the Brownian stress, kT/a 3 , and a characteristic stress based on the combination of interparticle force, i.e. σ ∼ F 0 /a 2 with kT the thermal energy, F 0 the repulsive force scale and a the particle radius. At sufficiently large ϕ, this shear thickening can be very abrupt. Here it is shown that when attractive interactions are present with the noted forces, the shear thickening is obscured, as the viscosity shear thins with increasing shear rate, eventually descending from an infinite value (yield stress conditions) to a plateau at large stress; this plateau is at the same level as the large-shear rate viscosity found in the shear thickened state without attractive forces. It is shown that this behavior is consistent with prior observations in shear thickening suspensions modified to be attractive through depletion flocculation [V. Gopalakrishnan and C. F. Zukoski J. Rheol., 2004, 48, 1321-1344]. The contributions of the contact, attractive, and hydrodynamics forces to the bulk stress are presented, as are the contact networks found at different attractive strengths.
Herndon, N
1992-08-01
In 1989, Pro-Pater, a private, nonprofit family planning organization in Brazil, used attractive ads with the message Vasectomy, An Act of Love to promote vasectomy. The number of vasectomies performed/day at Pro-Pater clinics increased from 11 to 20 during the publicity campaign and fell after the ads stopped but continued at higher levels. Word of mouth communication among friends, neighbors, and relatives who had vasectomies maintained these high levels. This type of communication reduced the fear that often involves vasectomies because men hear from men they know and trust that vasectomies are harmless and do not deprive them of potency. In Sao Paulo, the percentage of men familiar with vasectomies and how they are performed increased after the campaign, but in Salvador, knowledge did not increase even though the number of vasectomies in Pro-Pater clinics increased. Organizations in Colombia and Guatemala have also been effective in educating men about vasectomies. These successes were especially relevant in Latin American where machismo has been an obstacle of family planning programs. The no-scalpel technique 1st introduced in China in 1974 reduces the fear of vasectomy and has fewer complications than the conventional technique. Further trained physicians can perform the no-scalpel technique in about 10 minutes compared with 15 minutes for the conventional technique. In 1987 during a 1-day festival in Thailand, physicians averaged 57 no-scalpel vasectomies/day compared with only 33 for conventional vasectomies. This technique has not spread to Guatemala, Brazil, Colombia, the US, and some countries in Asia and Africa. Extensive research does not indicate that vasectomy has an increased risk of testicular cancer, prostate cancer, and myocardial infarction. Physicians are working on ways to improve vasectomy.
Beyond initial attraction: physical attractiveness in newlywed marriage.
McNulty, James K; Neff, Lisa A; Karney, Benjamin R
2008-02-01
Physical appearance plays a crucial role in shaping new relationships, but does it continue to affect established relationships, such as marriage? In the current study, the authors examined how observer ratings of each spouse's facial attractiveness and the difference between those ratings were associated with (a) observations of social support behavior and (b) reports of marital satisfaction. In contrast to the robust and almost universally positive effects of levels of attractiveness on new relationships, the only association between levels of attractiveness and the outcomes of these marriages was that attractive husbands were less satisfied. Further, in contrast to the importance of matched attractiveness to new relationships, similarity in attractiveness was unrelated to spouses' satisfaction and behavior. Instead, the relative difference between partners' levels of attractiveness appeared to be most important in predicting marital behavior, such that both spouses behaved more positively in relationships in which wives were more attractive than their husbands, but they behaved more negatively in relationships in which husbands were more attractive than their wives. These results highlight the importance of dyadic examinations of the effects of spouses' qualities on their marriages.
Judging attractiveness: Biases due to raters’ own attractiveness and intelligence
Directory of Open Access Journals (Sweden)
Stacy Yen-Lin Sim
2015-12-01
Full Text Available Tennis and Dabbs (1975 reported that physically attractive males showed a positivity bias when rating the attractiveness of others. The opposite pattern was observed for females. We attempted to replicate and extend these findings by: (1 using self-assessed attractiveness rather than the experimentally derived attractiveness measure used in previous research, (2 using face-to-face interactions with targets as opposed to using photographs, and (3 examining the effect of another ego-involving attribute: intelligence. Consistent with previous research, attractiveness judgments made by men, but not women, correlated positively with their own self-perceived level of attractiveness (r = .51, p < .001. Attractiveness judgments made by women, but not men, correlated negatively with their intelligence (r = −.32, p = .001. Judgments of attractiveness are thus biased by a rater’s own attributes (e.g. attractiveness and intelligence, but these effects are not generalizable across men and women raters, and may be driven by different mechanisms.
Three-body bound states of two bosonic impurities immersed in a Fermi sea in 2D
DEFF Research Database (Denmark)
Bellotti, F. F.; Frederico, T.; Yamashita, M. T.
2016-01-01
We consider two identical impurities immersed in a Fermi sea for a broad range of masses and for both interacting and non-interacting impurities. The interaction between the particles is described through attractive zero-range potentials and the problem is solved in momentum space. The two...
Renewable Energy Country Attractiveness Indices
International Nuclear Information System (INIS)
2011-02-01
Since 2003 Ernst and Young team has been releasing quarterly data that ranks national renewable energy markets, and their suitability for individual technologies. The Country Attractiveness Indices now track the relative attractiveness of 30 countries' renewable energy markets across a selection of technologies each quarter. The Renewable Energy Country Attractiveness Indices publication scores and comments on various technologies, including: on-shore wind, off-shore wind, solar PV, solar CSP, biomass, and geothermal.
Measurements of $C\\!P$ violation in the three-body phase space of charmless $B^{\\pm}$ decays
Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; van den Brand, Johannes; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; 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Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kaballo, Michael; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lu, Haiting; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pazos Alvarez, Antonio; Pearce, Alex; Pellegrino, Antonio; Pepe Altarelli, Monica; Perazzini, Stefano; Perez Trigo, Eliseo; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Roa Romero, Diego; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrie, Mauro; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Seco, Marcos; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szilard, Daniela; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; Voss, Helge; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wu, Suzhi; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander
2014-01-01
The charmless three-body decay modes $B^{\\pm} \\rightarrow K^{\\pm} \\pi^{+} \\pi^{-}$, $B^{\\pm} \\rightarrow K^{\\pm} K^{+} K^{-}$, $B^{\\pm} \\rightarrow \\pi^{\\pm} K^{+} K^{-}$ and $B^{\\pm} \\rightarrow \\pi^{\\pm} \\pi^{+} \\pi^{-}$ are reconstructed using data, corresponding to an integrated luminosity of 3.0 fb$^{-1}$, collected by the LHCb detector. The inclusive $C\\!P$ asymmetries of these modes are measured to be \\begin{eqnarray} A_{C\\!P}(B^{\\pm} \\rightarrow K^{\\pm} \\pi^{+} \\pi^{-})= +0.025 \\pm 0.004 \\pm 0.004 \\pm 0.007, \\end{eqnarray} \\begin{eqnarray} A_{C\\!P}(B^{\\pm} \\rightarrow K^{\\pm} K^{+} K^{-}) = -0.036 \\pm 0.004 \\pm 0.002 \\pm 0.007, \\end{eqnarray} \\begin{eqnarray} A_{C\\!P}(B^{\\pm} \\rightarrow \\pi^{\\pm} \\pi^{+} \\pi^{-})= +0.058 \\pm 0.008 \\pm 0.009 \\pm 0.007, \\end{eqnarray} \\begin{eqnarray} A_{C\\!P}(B^{\\pm} \\rightarrow \\pi^{\\pm} K^{+} K^{-})= -0.123 \\pm 0.017 \\pm 0.012 \\pm 0.007, \
International Nuclear Information System (INIS)
Boesten, L.G.J.
1978-01-01
Calculations on the threshold ionization of H, He + and Li 2+ by electrons have been performed to study the so-called 'post-collision interaction' (P.C.I.) effects which appear to affect the threshold ionization process significantly. These effects are caused by the long range Coulomb interactions between the two electrons as they move away from the nucleus. The long range interactions are fully taken into account in the classical three-body collision theory. In quantum mechanical theories, however, it is difficult to account for these interactions. This theory has been used to study the ionization of He + -ions by electron impact up to much higher energies (up till ten times the threshold energy). The results are compared with experimental results of Dolder et al. (1961) and with results of quantum mechanical calculations. Results are given for ionization of helium atoms by electron or proton impact. This collision process, in which four particles are involved, can under certain circumstances be treated as a collision process in which only three particles are involved. Calculations are performed concerning: a) cross sections for ionization of metastable helium atoms by electron impact, b) cross sections for ionization of ground-state helium atoms by fast proton impact (energy and angular distributions of ejected electrons), c) generalized oscillator strengths for ionization of helium by fast proton impact
Three-body decays of B{sup 0(+)} → K{sup *0(+)}π{sup +}π{sup -}
Energy Technology Data Exchange (ETDEWEB)
Mohammadi, Behnam; Mehraban, Hossein [Semnan University, Physics Department, Semnan (Iran, Islamic Republic of)
2014-08-15
We are interested in the analysis of the three-body decays of B{sup 0} → K{sup *0}π{sup +}π{sup -} and B{sup +} → K{sup *+}π{sup +}π{sup -}. There are tree and penguin diagrams for these decay modes in the naive factorization approach and the transition matrix element of them is factorized into a B → π{sup +}π{sup -} form factor multiplied by 0 → K{sup *} decay constant and B → K{sup *} form factor multiplied into 0 → π{sup +}π{sup -} weak and electromagnetic vertices form factor. We investigate these decays by using the Dalitz plot analysis. We use the general form of this technique for the calculation of the B{sup 0} → K{sup *0}π{sup +}π{sup -} and B{sup +} → K{sup *+}π{sup +}π{sup -} decays and obtain the values (3.74 ± 0.50) x 10{sup -5} and (9.64 ± 1.37) x 10{sup -5} for the branching ratios, while the experimental results are (5.50 ± 0.50) x 10{sup -5} and (7.50 ± 1.00) x 10{sup -5}, respectively. The branching ratios obtained by applying the Dalitz plot analysis are compatible with the experimental results. (orig.)
Guzzo, Massimiliano; Lega, Elena
2018-06-01
The circular restricted three-body problem has five relative equilibria L1 ,L2, . . . ,L5. The invariant stable-unstable manifolds of the center manifolds originating at the partially hyperbolic equilibria L1 ,L2 have been identified as the separatrices for the motions which transit between the regions of the phase-space which are internal or external with respect to the two massive bodies. While the stable and unstable manifolds of the planar problem have been extensively studied both theoretically and numerically, the spatial case has not been as deeply investigated. This paper is devoted to the global computation of these manifolds in the spatial case with a suitable finite time chaos indicator. The definition of the chaos indicator is not trivial, since the mandatory use of the regularizing Kustaanheimo-Stiefel variables may introduce discontinuities in the finite time chaos indicators. From the study of such discontinuities, we define geometric chaos indicators which are globally defined and smooth, and whose ridges sharply approximate the stable and unstable manifolds of the center manifolds of L1 ,L2. We illustrate the method for the Sun-Jupiter mass ratio, and represent the topology of the asymptotic manifolds using sections and three-dimensional representations.
Relativistic origin of three-nucleon force
International Nuclear Information System (INIS)
Haberzettl, H.; Parke, W.C.
1995-01-01
Based on the manifestly covariant cluster-dynamical formalism recently proposed by Haberzettl, the three-body forces entering three-nucleon equations are discussed. It is shown that there exist additional contributions to the (nonrelativistic) three-body force, not taken into account in the usual treatments, arising from the proper nonrelativistic limits of higher-order meson-exchange Feynman diagrams. Using the Paris potential, a five-channel triton bound-state calculation results in additional binding of about 0.6 MeV due to this new mechanism. copyright 1995 American Institute of Physics
Physical Attractiveness and Counseling Skills.
Vargas, Alice M.; Borkowski, John G.
1982-01-01
Searched for interaction between quality of counseling skills (presence or absence of empathy, genuineness, and positive regard) and physical attractiveness as determinants of counseling effectiveness. Attractiveness influenced perceived effectiveness of counselor's skill. Analyses of expectancy data revealed that only with good skills did…
Physical Attractiveness and Interpersonal Influence
Dion, Karen K.; Stein, Steven
1978-01-01
Examines the hypothesis that attractive individuals should be more successful with opposite-sex peers but less successful with same-sex peers than unattractive individuals. Also investigates the influence strategies employed by persons differing in attractiveness since nothing is currently known about the actual behavior exhibited by attractive…
Physical attractiveness stereotype and memory.
Rohner, Jean-Christophe; Rasmussen, Anders
2011-08-01
Three experiments examined explicit and implicit memory for information that is congruent with the physical attractiveness stereotype (i.e. attractive-positive and unattractive-negative) and information that is incongruent with the physical attractiveness stereotype (i.e. attractive-negative and unattractive-positive). Measures of explicit recognition sensitivity and implicit discriminability revealed a memorial advantage for congruent compared to incongruent information, as evident from hit and false alarm rates and reaction times, respectively. Measures of explicit memory showed a recognition bias toward congruent compared to incongruent information, where participants tended to call congruent information old, independently of whether the information had been shown previously or not. This recognition bias was unrelated to reports of subjective confidence in retrieval. The present findings shed light on the cognitive mechanisms that might mediate discriminatory behavior towards physically attractive and physically unattractive individuals. © 2011 The Authors. Scandinavian Journal of Psychology © 2011 The Scandinavian Psychological Associations.
Pulsations and period variations of the δ Scuti star AN Lyncis in a possible three-body system
Li, Gang; Fu, Jianning; Su, Jie; Fox-Machado, Lester; Michel, Raul; Guo, Zhen; Liu, Jinzhong; Feng, Guojie
2018-01-01
Observations for the δ Scuti star AN Lyn have been made between 2008 and 2016 with the 85-cm telescope at Xinglong station of National Astronomical Observatories of China, the 84-cm telescope at SPM Observatory of Mexico and the Nanshan One metre Wide field Telescope of Xinjiang Observatory of China. Data in V in 50 nights and in R in 34 nights are obtained in total. The bi-site observations from both Xinglong Station and SPM Observatory in 2014 are analysed with Fourier Decomposition to detect pulsation frequencies. Two independent frequencies are resolved, including one non-radial mode. A number of stellar model tracks are constructed with the MESA code and the fit of frequencies leads to the best-fitting model with the stellar mass of M = 1.70 ± 0.05 M⊙, the metallicity abundance of Z = 0.020 ± 0.001, the age of 1.33 ± 0.01 billion years and the period change rate 1/P · dP/dt = 1.06 × 10-9 yr-1, locating the star at the evolutionary stage close to the terminal age main sequence. The O-C diagram provides the period change rate of (1/P)(dP/dt) = 4.5(8) × 10-7 yr-1. However, the period change rate calculated from the models is smaller in two orders than the one derived from the O-C diagram. Together with the sinusoidal function signature, the period variations are regarded to be dominated by the light-travel time effect of the orbital motion of a three-body system with two low-luminosity components, rather than the stellar evolutionary effect.
Effects of student physical attractiveness
Directory of Open Access Journals (Sweden)
Krnjajić Stevan B.
2005-01-01
Full Text Available Implicit personality theories suggest that people draw conclusions about other persons by using a relatively small number of visible features. The formation of "the first impression" is influenced by the factors, such as sex, age, appearances, race or nationality. Frequently, conclusions based on those factors lead to developing social stereotypes. Attractiveness is a good example of "the first impression" effect, because physical attractiveness entails the creation of impression about another person along a relatively great number of dimensions. Experimental paradigm, introduced in the sphere of interpersonal perception around the mid-20th century, led to a relatively great number of studies on stereotype based on physical attractiveness. One of the most often quoted conclusions of studies on physical attractiveness is summarized by the idiom "what is beautiful is good". For example, socially desirable personality traits (responsibility kindness, energy quality, modesty, more successful private and professional life, are all attributed to physically attractive persons. In addition physical attractiveness is coupled with positive expectations, peer acceptance, academic achievement etc. On the basis of studies on the "what is beautiful is good" stereotype, we have situated our analysis within the domain of roles regulating social interaction between teachers and students i.e. effects of physical attractiveness on teacher expectations, peer acceptance and academic achievement.
International Nuclear Information System (INIS)
Cirone, M.A.; Schleich, W.P.; Straub, F.; Rzazewski, K.; Wheeler, J.A.
2002-01-01
In a two-dimensional world, a free quantum particle of vanishing angular momentum experiences an attractive force. This force originates from a modification of the classical centrifugal force due to the wave nature of the particle. For positive energies the quantum anticentrifugal force manifests itself in a bunching of the nodes of the energy wave functions towards the origin. For negative energies this force is sufficient to create a bound state in a two-dimensional δ-function potential. In a counterintuitive way, the attractive force pushes the particle away from the location of the δ-function potential. As a consequence, the particle is localized in a band-shaped domain around the origin
Attractiveness bias: A cognitive explanation.
Schein, Stevie S; Trujillo, Logan T; Langlois, Judith H
2017-01-01
According to cognitive averaging theory, preferences for attractive faces result from their similarity to facial prototypes, the categorical central tendencies of a population of faces. Prototypical faces are processed more fluently, resulting in increased positive affect in the viewer.
Creating kampong as tourist attractions
Sari, N.; Utama, R.; Hidayat, A. R. T.; Zamrony, A. B.
2017-06-01
Tourism attractions become one of the main components and they drive the tourism activity in a region. The quality of tourism attractions would affect tourists’ visits. Tourism power can basically be built on any conditions which can attract people to visit. Towns is full of activities which include their economic, social, cultural and physical features, if they are presented properly, they can be a tourist attraction. Kampung City, as a form of urban settlement, has the potential to be developed as a tourism attraction. Kampung is not only a physical area of housing but it has also productive activities. Even the city’s economic activities are also influenced by the productive activities of its Kampung. The shape of Kampung which varies in physical, social, economic and cultural raises special characteristics of each Kampung. When it is linked with the city’s tourism activities, these special characteristics of course could be one of the attractions to attract tourists. This paper studies about one of Kampung in the Malang City. Administratively located in the Penanggungan Village Lowokwaru District, but the potential will just be focused on RW 4. Main productive activities of this village are pottery. In contrast to ceramics, pottery is made from clay and its uniqueness in color and shape. Based on the history of pottery in the Malang, it is concentrated in Penanggungan Village. But along with its development, pottery is decreasingly in demand and number of craftsmen is dwindling. Based on these circumstances, a concept is prepared to raise the image of the region as the Kampung of pottery and to repack it as a tourism attraction of the city.
Effects of student physical attractiveness
Krnjajić Stevan B.
2005-01-01
Implicit personality theories suggest that people draw conclusions about other persons by using a relatively small number of visible features. The formation of "the first impression" is influenced by the factors, such as sex, age, appearances, race or nationality. Frequently, conclusions based on those factors lead to developing social stereotypes. Attractiveness is a good example of "the first impression" effect, because physical attractiveness entails the creation of impression about anothe...
[Sexual attraction: a concept analysis using an evolutionary perspective].
Yang, Shu-Chin; Chu, Chun-Hong; Lu, Zxy-Yann Jane
2015-02-01
Medical technology has transformed the body image of women and altered perceptions of beauty and sexual attraction. While "sexual attraction" is a fundamental concept in sexology, the characteristics of this concept have not been studied in the field of nursing. Because nurses provide advice and health education for women, it is essential to clarify the concept of sexual attraction for the benefit of related nursing research and for the further development of nursing knowledge. This study explores the concept of sexual attraction in a Taiwanese social context using concept analysis based on an evolutionary perspective. Inductive inquiry is used to compare and contrast articles from the academic literature, magazines, and newspapers, and data from participant observation and interviews are used to generate exemplars. The process by which the concept of sexual attraction has evolved over time is captured from three distinct aspects: significance, use, and application. The definitional statement of sexual attraction includes the five dimensions of: 1. sexual-oriented psychological dynamics; 2. personal aesthetics and sensory experience; 3. instinct body forces; 4. body language of self; and 5. social and cultural norms. This study scrutinized the changes in attributes that emphasize the biological, objectified body, and stereotyped gender roles of women. Further directions for research and nursing knowledge development are suggested. Examples include identifying the changes in the concept of sexual attraction that result from technological advancement and further clarifying the experiential knowledge of sexual attraction that represents the selfhood and independence of women in Taiwan.
International Nuclear Information System (INIS)
Ueta, K.
1988-12-01
It is shown that a separable potential previously used to describe a 2s 1/2 single-particle state gives rise not only to a bound state but also to a resonance of the core-plus-two-nucleons three-body system. (author) [pt
Mutual attraction of magnetic knots
International Nuclear Information System (INIS)
Parker, E.N.
1978-01-01
It is observed that the magnetic knots associated with active regions on the Sun have an attraction for each other during the formative period of the active regions, when new magnetic flux is coming to the surface. The attraction disappears when new flux ceases to rise through the surface. Then the magnetic spots and knots tend to come apart, leading to disintegration of the sunspots previously formed. The dissolution of the fields is to be expected, as a consequence of the magnetic repulsion of knots of like polarity and as a consequence of the hydromagnetic exchange instability.The purpose of this paper is to show that the mutual attraction of knots during the formative stages of a sunspot region may be understood as the mutual hydrodynamic attraction of the rising flux tubes. Two rising tubes attract each other, as a consequence of the wake of the leading tube when one is moving behind the other, and as a consequence of the Bernoulli effect when rising side by side
Heritability of attractiveness to mosquitoes.
Directory of Open Access Journals (Sweden)
G Mandela Fernández-Grandon
Full Text Available Female mosquitoes display preferences for certain individuals over others, which is determined by differences in volatile chemicals produced by the human body and detected by mosquitoes. Body odour can be controlled genetically but the existence of a genetic basis for differential attraction to insects has never been formally demonstrated. This study investigated heritability of attractiveness to mosquitoes by evaluating the response of Aedes aegypti (=Stegomyia aegypti mosquitoes to odours from the hands of identical and non-identical twins in a dual-choice assay. Volatiles from individuals in an identical twin pair showed a high correlation in attractiveness to mosquitoes, while non-identical twin pairs showed a significantly lower correlation. Overall, there was a strong narrow-sense heritability of 0.62 (SE 0.124 for relative attraction and 0.67 (0.354 for flight activity based on the average of ten measurements. The results demonstrate an underlying genetic component detectable by mosquitoes through olfaction. Understanding the genetic basis for attractiveness could create a more informed approach to repellent development.
Attractive ellipsoids in robust control
Poznyak, Alexander; Azhmyakov, Vadim
2014-01-01
This monograph introduces a newly developed robust-control design technique for a wide class of continuous-time dynamical systems called the “attractive ellipsoid method.” Along with a coherent introduction to the proposed control design and related topics, the monograph studies nonlinear affine control systems in the presence of uncertainty and presents a constructive and easily implementable control strategy that guarantees certain stability properties. The authors discuss linear-style feedback control synthesis in the context of the above-mentioned systems. The development and physical implementation of high-performance robust-feedback controllers that work in the absence of complete information is addressed, with numerous examples to illustrate how to apply the attractive ellipsoid method to mechanical and electromechanical systems. While theorems are proved systematically, the emphasis is on understanding and applying the theory to real-world situations. Attractive Ellipsoids in Robust Control will a...
Dynamics of a Liquid Dielectric Attracted by a Cylindrical Capacitor
Nardi, Rafael; Lemos, Nivaldo A.
2007-01-01
The dynamics of a liquid dielectric attracted by a vertical cylindrical capacitor are studied. Contrary to what might be expected from the standard calculation of the force exerted by the capacitor, the motion of the dielectric is different depending on whether the charge or the voltage of the capacitor is held constant. The problem turns out to…
The influence of planetary attractions on the solar tachocline
Callebaut, D.K.; de Jager, C.; Duhau, S.
2012-01-01
We present a physical analysis of the occasionally forwarded hypothesis that solar variability, as shown in the various photospheric and outer solar layer activities, might be due to the Newtonian attraction by the planets. We calculate the planetary forces exerted on the tachocline and thereby not
Island formation without attractive interaction
Jansen, A.P.J.
2008-01-01
We show that adsorbates on surfaces can form islands even if there are no attractive interactions. Instead, strong repulsion between adsorbates at short distances can lead to islands, because such islands increase the entropy of the adsorbates that are not part of the islands. We suggest that this
Physical Attractiveness, Employment, and Earnings
Christian Pfeifer
2011-01-01
Survey data is used to estimate the impact of physical attractiveness rated by the interviewer as well as by the respondent on employment probability and labor income of men and women. In addition to mean linear and non-linear effects on earnings, simultaneous quantile regressions are applied to analyze heterogeneity across the wage distribution.
The Ambiguous Attractiveness of Mobility
DEFF Research Database (Denmark)
Presskorn-Thygesen, Thomas
2015-01-01
’ can help us understand the attractiveness of constantly being ‘on the move’. Qualitative data from three exemplars of this elite group of workers is used to illustrate how the ideal of being mobile is perceived as an often problematic imperative, but also as one which is nevertheless rewarding...
Three-nucleon forces and the trinucleon bound states
International Nuclear Information System (INIS)
Friar, J.L.; Frois, B.
1986-04-01
A summary of the bound-state working group session of the ''International Symposium on the Three-Body Force in the Three-Nucleon System'' is presented. The experimental evidence for three-nucleon forces has centered on two ground state properties: the tritium binding energy and the trinucleon form factors. Both are discussed
DEFF Research Database (Denmark)
Bialynicki-Birula, I; Cirone, M.A.; Dahl, Jens Peder
2002-01-01
We present Heisenberg's equation of motion for the radial variable of a free non-relativistic particle in D dimensions. The resulting radial force consists of three contributions: (i) the quantum fictitious force which is either attractive or repulsive depending on the number of dimensions, (ii......) a singular quantum force located at the origin, and (iii) the centrifugal force associated with non-vanishing angular momentum. Moreover, we use Heisenberg's uncertainty relation to introduce a lower bound for the kinetic energy of an ensemble of neutral particles. This bound is quadratic in the number...... of atoms and can be traced back to the repulsive quantum fictitious potential. All three forces arise for a free particle: "Force without force"....
Three-body models of the 6ΛΛHe and 9ΛBe hypernuclei with non-local interactions
International Nuclear Information System (INIS)
Theeten, M.; Baye, D.; Descouvemont, P.
2005-01-01
A three-body model involving non-local interactions is developed in configuration space. It is based on a hyperspherical-harmonics expansion and the Lagrange-mesh method. The 6 ΛΛ He and 9 Λ Be hypernuclei are studied as three-body αΛΛ and ααΛ systems. Recently proposed quark-model based ΛN and ΛΛ interactions are used. A non-local Λα interaction is obtained by folding the ΛN interaction with a Gaussian α density. Various phenomenological αα interactions are employed. The results agree within 1 keV with recent Faddeev calculations in momentum space. Energies and radii of 6 ΛΛ He and 9 Λ Be are compared with a purely local model. The B(E2) between the 9 Λ Be bound states is also calculated. The role of non-locality is discussed
The role of three-body coulomb fields versus final state interactions in the decay of 12C-α-12C
International Nuclear Information System (INIS)
Quebert, J.L.; Bertault, D.; Scheurer, J.N.; Fouan, J.P.
1980-01-01
The alpha emission in 16 O + 12 C→ 12 C + α + 12 C has been thoroughly studied in the region of the rapidity plot: Ysub(α)=Ysub(c.m.). The three-body coulomb fields, as well as configurations close to alignment, account for the alpha yield which is observed. The apparent competition between direct and sequential decays is well explained by the coulomb break-up
MacDonald, Matthew
2010-01-01
To be a success, a website has to attract-and keep--visitors. This Mini Missing Manual shows you how to attract new and return visitors and use the power of keywords and Web search engines to rise up in the rankings of search results. You'll also learn how to use a powerful-and free--service that tracks visitor activity on your site so you know which of your Web pages they love, and-just as important--which pages don't work for them. Using this information, you can fine-tune your site to keep the visitors coming. This Mini Missing Manual is excerpted from Creating a Web Site: The Missing Man
St-Jean, Audray; Meziou, Salma; Ayotte, Pierre; Lucas, Michel
2017-11-22
Little is known about the suitability of three commonly used body mass index (BMI) classification systems for Indigenous youth. We estimated overweight and obesity prevalence among Cree youth of Eeyou Istchee according to three BMI classification systems, assessed the level of agreement between them, and evaluated their accuracy through body fat and cardiometabolic risk factors. Data on 288 youth (aged 8-17 years) were collected. Overweight and obesity prevalence were estimated with Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF) and World Health Organization (WHO) criteria. Agreement was measured with weighted kappa (κw). Associations with body fat and cardiometabolic risk factors were evaluated by analysis of variance. Obesity prevalence was 42.7% with IOTF, 47.2% with CDC, and 49.3% with WHO criteria. Agreement was almost perfect between IOTF and CDC (κw = 0.93), IOTF and WHO (κw = 0.91), and WHO and CDC (κw = 0.94). Means of body fat and cardiometabolic risk factors were significantly higher (P trend obesity, regardless of the system used. Youth considered overweight by IOTF but obese by CDC or WHO exhibited less severe clinical obesity. IOTF seems to be more accurate in identifying obesity in Cree youth.
Attracting finance for hydroelectric power
International Nuclear Information System (INIS)
Besant-Jones, John
1996-01-01
Hydroelectricity will continue to be important for meeting power requirements in developing countries. Much of the funding required for hydroelectric projects must come from non-government source; hydroelectric projects will therefore need to be attractive to private investors. This note explores the risks investors face, how this can be mitigated, and how the World Bank group can offer advice (as well as finance) to member countries to facilitate investment in hydro electric projects. 3 refs., 1 fig
Branner-Hubbard Motions and attracting dynamics
DEFF Research Database (Denmark)
Petersen, Carsten Lunde; Tan, Lei
2006-01-01
We introduce a new notion of attracting dynamics, which is related to polynomial-like mappings. Also we review the Branner-Hubbard Motion and study its action on attracting dynamics.......We introduce a new notion of attracting dynamics, which is related to polynomial-like mappings. Also we review the Branner-Hubbard Motion and study its action on attracting dynamics....
Structure of DNA toroids and electrostatic attraction of DNA duplexes
International Nuclear Information System (INIS)
Cherstvy, A G
2005-01-01
DNA-DNA electrostatic attraction is considered as the driving force for the formation of DNA toroids in the presence of DNA condensing cations. This attraction comes from the DNA helical charge distribution and favours hexagonal toroidal cross-sections. The latter is in agreement with recent cryo-electron microscopy studies on DNA condensed with cobalt hexammine. We treat the DNA-DNA interactions within the modern theory of electrostatic interaction between helical macromolecules. The size and thickness of the toroids is calculated within a simple model; other models of stability of DNA toroids are discussed and compared
Individual differences in valuing mates' physical attractiveness.
Mathes, Eugene W; Bielser, Abby; Cassell, Ticcarra; Summers, Sarah; Witowski, Aggie
2006-10-01
To investigate correlates of valuing physical attractiveness in a mate, it was hypothesized that valuing physical attractiveness in a mate would correlate with sex and valuing promiscuous sex, status, personal physical attractiveness, beauty, and order. Men and women college students completed measures of the extent to which they valued physical attractiveness in a mate and other variables. Valuing physical attractiveness in a mate was correlated with sex (men valued physical attractiveness in a mate more than did women) and valuing promiscuous sex and status, and, for women, valuing personal physical attractiveness. The results were explained in terms of evolutionary theory.
Predators are attracted to the olfactory signals of prey.
Directory of Open Access Journals (Sweden)
Nelika K Hughes
2010-09-01
Full Text Available Predator attraction to prey social signals can force prey to trade-off the social imperatives to communicate against the profound effect of predation on their future fitness. These tradeoffs underlie theories on the design and evolution of conspecific signalling systems and have received much attention in visual and acoustic signalling modes. Yet while most territorial mammals communicate using olfactory signals and olfactory hunting is widespread in predators, evidence for the attraction of predators to prey olfactory signals under field conditions is lacking.To redress this fundamental issue, we examined the attraction of free-roaming predators to discrete patches of scents collected from groups of two and six adult, male house mice, Mus domesticus, which primarily communicate through olfaction. Olfactorily-hunting predators were rapidly attracted to mouse scent signals, visiting mouse scented locations sooner, and in greater number, than control locations. There were no effects of signal concentration on predator attraction to their prey's signals.This implies that communication will be costly if conspecific receivers and eavesdropping predators are simultaneously attracted to a signal. Significantly, our results also suggest that receivers may be at greater risk of predation when communicating than signallers, as receivers must visit risky patches of scent to perform their half of the communication equation, while signallers need not.
Observation of attractive and repulsive polarons in a Bose-Einstein condensate
DEFF Research Database (Denmark)
Jørgensen, Nils Byg
2016-01-01
(BEC) has not yet been realized. Here, we use radio frequency spectroscopy of ultracold bosonic 39K atoms to experimentally demonstrate the existence of a well-defined quasiparticle state of an impurity interacting with a BEC. We measure the energy of the impurity both for attractive and repulsive...... interactions, and find excellent agreement with theories that incorporate three-body correlations. The spectral response consists of a well-defined quasiparticle peak at weak coupling, while for increasing interaction strength, the spectrum is strongly broadened and becomes dominated by the many-body continuum...
Stability and decay rates of nonisotropic attractive Bose-Einstein condensates
International Nuclear Information System (INIS)
Huepe, C.; Tuckerman, L. S.; Metens, S.; Brachet, M. E.
2003-01-01
Nonisotropic attractive Bose-Einstein condensates are investigated numerically with Newton and inverse Arnoldi methods. The stationary solutions of the Gross-Pitaevskii equation and their linear stability are computed. Bifurcation diagrams are calculated and used to find the condensate decay rates corresponding to macroscopic quantum tunneling, two-three-body inelastic collisions, and thermally induced collapse. Isotropic and nonisotropic condensates are compared. The effect of anisotropy on the bifurcation diagram and the decay rates is discussed. Spontaneous isotropization of the condensates is found to occur. The influence of isotropization on the decay rates is characterized near the critical point
Dynamics of a particle attracted by a magnetized wire
International Nuclear Information System (INIS)
Lawson, W.F. Jr.; Simons, W.H.; Treat, R.P.
1977-01-01
The dynamics of a particle attracted by a magnetized wire is studied for nonvanishing gravitational forces and a broad range of Stokes number K. The Newtonian equation of motion for the particle is integrated for 10 -2 2 , a range which includes conditions where the particle inertia cannot be ignored. Families of trajectories, typical of low and high K, reveal the dominance of viscous forces at low K, as expected, and show oscillatory approach to capture for high K, where inertia is significant. Capture distances in the interval 1< or =X/sub c/< or =8 are given as a function of three independent dimensionless parameters which measure the strengths of the magnetic, viscous, and gravitational forces. The range of conditions is established for which it is permissible to neglect, for the purpose of computing capture distances, both the inertia and the radially attractive short-range part of the magnetic force. The equation of motion in which the inertia and the short-range term are neglected is studied. An integral of this equation is found which extends the trajectory equations of Zebel and Luborsky to include the gravitational force. A general approach to the construction of the integral of motion shows how to find the trajectory equation for a particle moving in a more complicated incompressible viscous flow with higher multipole contributions to the magnetic field of force
Facial attractiveness, symmetry, and physical fitness in young women.
Hönekopp, Johannes; Bartholomé, Tobias; Jansen, Gregor
2004-06-01
This study explores the evolutionary-based hypothesis that facial attractiveness (a guiding force in mate selection) is a cue for physical fitness (presumably an important contributor to mate value in ancestral times). Since fluctuating asymmetry, a measure of developmental stability, is known to be a valid cue for fitness in several biological domains, we scrutinized facial asymmetry as a potential mediator between attractiveness and fitness. In our sample of young women, facial beauty indeed indicated physical fitness. The relationships that pertained to asymmetry were in the expected direction. However, a closer analysis revealed that facial asymmetry did not mediate the relationship between fitness and attractiveness. Unexpected problems regarding the measurement of facial asymmetry are discussed.
Potential dependence of the effective attraction in doped C60
International Nuclear Information System (INIS)
Goff, W.E.; Phillips, P.
1992-01-01
In an effort to explain superconductivity in the alkali-doped C 60 , Chakravarty and Kivelson have proposed that there is a net effective electron attraction due to intramolecular Coulomb forces. The calculation makes use of a Hubbard model in which long-range interactions are absent. The authors show that this result strongly depends on the form of the electron-electron interaction and that for potentials with long-range interactions, e.g. an Ohno potential that interpolates between an on site energy and 1/r at large distances, they do not find an effective attraction. Reasonable screening does not significantly modify this result. This indicates that the electronic mechanism in the proposed form cannot be the primary source of an attractive interaction
International Nuclear Information System (INIS)
Szalewicz, K.; Monkhorst, H.J.
1986-04-01
A solution of the Coulomb three-body problem is the beginning point for calculations of sticking fractions in muon catalyzed fusion. The basis set is constructed from the following functions xi/sup r/n/sup s/e/sup - αxi - β n/R/sup -3 /2//H/sub eta/(x)exp(-x 2 /2), where xi and eta are elliptic coordinates of muon, R is the internuclear distance, H/sub eta/ is the nth Hermite polynomial, and x = γ (R-R/sub e/). The nonlinear parameters α, β, γ, and R/sub e/ are to be optimized. 21 refs., 1 tab
International Nuclear Information System (INIS)
Kazantzis, P.G.
1979-01-01
New families of three-dimensional double-symmetric periodic orbits are determined numerically in the Sun-Jupiter case of the restricted three-body problem. These families bifurcate from the 'vertical-critical' orbits (αsub(ν) = -1, csub(ν) = 0) of the 'basic' plane families i. g 1 g 2 h, a, m and I. Further the numerical procedure employed in the determination of these families has been described and interesting results have been pointed out. Also, computer plots of the orbits of these families have been shown in conical projections. (orig.)
van Osch, Y.M.J.; Blanken, Irene; Meijs, Maartje H. J.; van Wolferen, Job
2015-01-01
We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of
Attractive electromagnetic Casimir stress on a spherical dielectric shell
International Nuclear Information System (INIS)
Graham, N.; Quandt, M.; Weigel, H.
2013-01-01
Based on calculations involving an idealized boundary condition, it has long been assumed that the stress on a spherical conducting shell is repulsive. We use the more realistic case of a Drude dielectric to show that the stress is attractive, matching the generic behavior of Casimir forces in electromagnetism. We trace the discrepancy between these two cases to interactions between the electromagnetic quantum fluctuations and the dielectric material
Mate attraction, retention and expulsion.
Miner, Emily J; Shackelford, Todd K
2010-02-01
Sexual selection theory and parental investment theory have guided much of the evolutionary psychological research on human mating. Based on these theories, researchers have predicted and found sex differences in mating preferences and behaviors. Men generally prefer that their long-term partners are youthful and physically attractive. Women generally prefer that their long-term partners have existing resources or clear potential for securing resources and display a willingness to invest those resources in children the relationship might produce. Both men and women, however, desire long-term partners who are kind and intelligent. Once a partner is obtained, men and women act in sex-specific ways to ensure the continuation and exclusivity of the relationship. Men, in particular, engage in behaviors designed to prevent, correct, and anticipate their partner's sexual infidelity. Relationships dissolve for evolutionarily-relevant reasons: infidelity, childlessness, and infertility. The discussion addresses directions for future research.
Spin Modes in Nuclei and Nuclear Forces
International Nuclear Information System (INIS)
Suzuki, Toshio; Otsuka, Takaharu
2011-01-01
Spin modes in stable and unstable exotic nuclei are studied and important roles of tensor and three-body forces on nuclear structure are discussed. New shell model Hamiltonians, which have proper tensor components, are shown to explain shell evolutions toward drip-lines and spin properties of both stable and exotic nuclei, for example, Gamow-Teller transitions in 12 C and 14 C and an anomalous M1 transition in 17 C. The importance and the necessity of the repulsive monopole corrections in isospin T = 1 channel to the microscopic two-body interactions are pointed out. The corrections are shown to lead to the proper shell evolutions in neutron-rich isotopes. The three-body force, in particular the Fujita-Miyazawa force induced by Δ excitations, is pointed out to be responsible for the repulsive corrections among the valence neutrons. The important roles of the three-body force on the energies and transitions in exotic oxygen and calcium isotopes are demonstrated.
Brahim, Bessem; Tabet, Jean-Claude; Alves, Sandra
2018-02-01
Gas-phase fragmentation of single strand DNA-peptide noncovalent complexes is investigated in positive and negative electrospray ionization modes.Collision-induced dissociation experiments, performed on the positively charged noncovalent complex precursor ions, have confirmed the trend previously observed in negative ion mode, i.e. a high stability of noncovalent complexes containing very basic peptidic residues (i.e. R > K) and acidic nucleotide units (i.e. Thy units), certainly incoming from the existence of salt bridge interactions. Independent of the ion polarity, stable noncovalent complex precursor ions were found to dissociate preferentially through covalent bond cleavages of the partners without disrupting noncovalent interactions. The resulting DNA fragment ions were found to be still noncovalently linked to the peptides. Additionally, the losses of an internal nucleic fragment producing "three-body" noncovalent fragment ions were also observed in both ion polarities, demonstrating the spectacular salt bridge interaction stability. The identical fragmentation patterns (regardless of the relative fragment ion abundances) observed in both polarities have shown a common location of salt bridge interaction certainly preserved from solution. Nonetheless, most abundant noncovalent fragment ions (and particularly three-body ones) are observed from positively charged noncovalent complexes. Therefore, we assume that, independent of the preexisting salt bridge interaction and zwitterion structures, multiple covalent bond cleavages from single-stranded DNA/peptide complexes rely on an excess of positive charges in both electrospray ionization ion polarities.
Emerging Market Attractiveness Index for hydro IPPs
Weaver, Tyson John
2013-01-01
This article addresses two primary commercial themes that affect the future development of the industry. 1. What are the most attractive future emerging markets for hydropower? 2. What parameters are utilized by international hydro IPPs to determine market attractiveness?
Screening for attractants compatible with entomopathogenic fungus ...
African Journals Online (AJOL)
RACHEL
2016-04-27
Apr 27, 2016 ... Several thrips attractants were screened for compatibility with Metarhizium anisopliae (Metchnikoff). Sorokin (Hypocreales: Clavicipitaceae) and a subset of these for attraction to Megalurothrips sjostedti. Trybom (Thysanoptera: Thripidae). Conidial germination and germ tube length of M. anisopliae were.
Evaluating self and partner physical attractiveness.
Swami, Viren; Furnham, Adrian; Georgiades, Chrissa; Pang, Lily
2007-03-01
This study used a novel questionnaire to examine ratings of self and partner physical attractiveness. Seventy-two men and 83 women estimated their own and their opposite-sex partner's overall physical attractiveness and the attractiveness of various body parts and measures. They also answered six simple questions concerning physical attractiveness. Results showed significant gender differences in self-estimates of overall facial attractiveness and upper body features. In general, and regardless of gender, participants rated their opposite-sex partners as being significantly more attractive than themselves. In addition, the results showed that body weight and facial attractiveness were the best predictors of overall physical attractiveness. Implications of these results in terms of social biases are considered.
Quantitative Methods to Evaluate Timetable Attractiveness
DEFF Research Database (Denmark)
Schittenhelm, Bernd; Landex, Alex
2009-01-01
The article describes how the attractiveness of timetables can be evaluated quantitatively to ensure a consistent evaluation of timetables. Since the different key stakeholders (infrastructure manager, train operating company, customers, and society) have different opinions on what an attractive...
Jamming transitions induced by an attraction in pedestrian flow
Kwak, Jaeyoung; Jo, Hang-Hyun; Luttinen, Tapio; Kosonen, Iisakki
2017-08-01
We numerically study jamming transitions in pedestrian flow interacting with an attraction, mostly based on the social force model for pedestrians who can join the attraction. We formulate the joining probability as a function of social influence from others, reflecting that individual choice behavior is likely influenced by others. By controlling pedestrian influx and the social influence parameter, we identify various pedestrian flow patterns. For the bidirectional flow scenario, we observe a transition from the free flow phase to the freezing phase, in which oppositely walking pedestrians reach a complete stop and block each other. On the other hand, a different transition behavior appears in the unidirectional flow scenario, i.e., from the free flow phase to the localized jam phase and then to the extended jam phase. It is also observed that the extended jam phase can end up in freezing phenomena with a certain probability when pedestrian flux is high with strong social influence. This study highlights that attractive interactions between pedestrians and an attraction can trigger jamming transitions by increasing the number of conflicts among pedestrians near the attraction. In order to avoid excessive pedestrian jams, we suggest suppressing the number of conflicts under a certain level by moderating pedestrian influx especially when the social influence is strong.
Jamming transitions induced by an attraction in pedestrian flow.
Kwak, Jaeyoung; Jo, Hang-Hyun; Luttinen, Tapio; Kosonen, Iisakki
2017-08-01
We numerically study jamming transitions in pedestrian flow interacting with an attraction, mostly based on the social force model for pedestrians who can join the attraction. We formulate the joining probability as a function of social influence from others, reflecting that individual choice behavior is likely influenced by others. By controlling pedestrian influx and the social influence parameter, we identify various pedestrian flow patterns. For the bidirectional flow scenario, we observe a transition from the free flow phase to the freezing phase, in which oppositely walking pedestrians reach a complete stop and block each other. On the other hand, a different transition behavior appears in the unidirectional flow scenario, i.e., from the free flow phase to the localized jam phase and then to the extended jam phase. It is also observed that the extended jam phase can end up in freezing phenomena with a certain probability when pedestrian flux is high with strong social influence. This study highlights that attractive interactions between pedestrians and an attraction can trigger jamming transitions by increasing the number of conflicts among pedestrians near the attraction. In order to avoid excessive pedestrian jams, we suggest suppressing the number of conflicts under a certain level by moderating pedestrian influx especially when the social influence is strong.
On the modulispace of attracting dynamics
DEFF Research Database (Denmark)
Petersen, Carsten Lunde
An Attracting Dynamics is a triple (f,W,a), where W is an open subset of the R(iemann) S(phere), f is a holomorphic map from W into the RS and a is an attracting periodic point for f. Denote by B(a) the attracted basin of the orbit of a for f. Two attracting dynamics (f,W,a) and (f',W',a') are i...
On Being "Attractive" With Resistant Clients.
Miller, Mark J.; Wells, Don
1990-01-01
Calls client resistance a frequent occurrence within the helping profession. Defines client resistance, provides a brief review of related literature, and offers counselor attractiveness as one way of addressing the issue. Identifies attractive counselor behaviors and attitudes and presents case study illustrating specific attractive counselor…
Tourism Attraction Systems. Exploring cultural behavior
Richards, G.W.
2002-01-01
Attractions are vital sub-elements in all whole tourism systems, and yet their study suffers from lack of theoretical depth and empirical foundation. This paper presents an empirical exploration of the attraction system model, based on a survey of over 6,000 tourists to cultural attractions. The
van Osch, Yvette; Blanken, Irene; Meijs, Maartje H J; van Wolferen, Job
2015-04-01
We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of physical attractiveness are more positive than the average ratings of the group members. A meta-analysis on 33 comparisons reveals that the effect is medium to large (Cohen's d = 0.60) and moderated by group size. We explored two explanations for the GA-effect: (a) selective attention to attractive group members, and (b) the Gestalt principle of similarity. The results of our studies are in favor of the selective attention account: People selectively attend to the most attractive members of a group and their attractiveness has a greater influence on the evaluation of the group. © 2015 by the Society for Personality and Social Psychology, Inc.
Nonlinear dynamics of attractive magnetic bearings
Hebbale, K. V.; Taylor, D. L.
1987-01-01
The nonlinear dynamics of a ferromagnetic shaft suspended by the force of attraction of 1, 2, or 4 independent electromagnets is presented. Each model includes a state variable feedback controller which has been designed using the pole placement method. The constitutive relationships for the magnets are derived analytically from magnetic circuit theory, and the effects of induced eddy currents due to the rotation of the journal are included using Maxwell's field relations. A rotor suspended by four electro-magnets with closed loop feedback is shown to have nine equilibrium points within the bearing clearance space. As the rotor spin speed increases, the system is shown to pass through a Hopf bifurcation (a flutter instability). Using center manifold theory, this bifurcation can be shown to be of the subcritical type, indicating an unstable limit cycle below the critical speed. The bearing is very sensitive to initial conditions, and the equilibrium position is easily upset by transient excitation. The results are confirmed by numerical simulation.
The Impact of Female Attractiveness in Spy
Pangjaya, Veronika Juliani; Handojo, Priska Febrinia
2017-01-01
This thesis discusses the impact of female attractiveness on the female character which is related to the way Spy sees attractive women and what the impacts to them are. There are criteria for female attractiveness that are displayed by the film such as physical attributes and traits. In order to show the criteria of attractive women and the responses that they get, I use stereotyping theory. Women who are physically attractive get better treatment, but in order to get that, they have to dres...
High Heels Increase Women's Attractiveness.
Guéguen, Nicolas
2015-11-01
Research has found that the appearance of women's apparel helps increase their attractiveness as rated by men and that men care more about physical features in potential opposite-sex mates. However, the effect of sartorial appearance has received little interest from scientists. In a series of studies, the length of women's shoe heels was examined. A woman confederate wearing black shoes with 0, 5, or 9 cm heels asked men for help in various circumstances. In Study 1, she asked men to respond to a short survey on gender equality. In Study 2, the confederate asked men and women to participate in a survey on local food habit consumption. In Study 3, men and women in the street were observed while walking in back of the female confederate who dropped a glove apparently unaware of her loss. It was found that men's helping behavior increased as soon as heel length increased. However, heel length had no effect on women's helping behavior. It was also found that men spontaneously approached women more quickly when they wore high-heeled shoes (Study 4). Change in gait, foot-size judgment, and misattribution of sexiness and sexual intent were used as possible explanations.
Attracting Girls into Physics (abstract)
Gadalla, Afaf
2009-04-01
A recent international study of women in physics showed that enrollment in physics and science is declining for both males and females and that women are severely underrepresented in careers requiring a strong physics background. The gender gap begins early in the pipeline, from the first grade. Girls are treated differently than boys at home and in society in ways that often hinder their chances for success. They have fewer freedoms, are discouraged from accessing resources or being adventurous, have far less exposure to problem solving, and are not encouraged to choose their lives. In order to motivate more girl students to study physics in the Assiut governorate of Egypt, the Assiut Alliance for the Women and Assiut Education District collaborated in renovating the education of physics in middle and secondary school classrooms. A program that helps in increasing the number of girls in science and physics has been designed in which informal groupings are organized at middle and secondary schools to involve girls in the training and experiences needed to attract and encourage girls to learn physics. During implementation of the program at some schools, girls, because they had not been trained in problem-solving as boys, appeared not to be as facile in abstracting the ideas of physics, and that was the primary reason for girls dropping out of science and physics. This could be overcome by holding a topical physics and technology summer school under the supervision of the Assiut Alliance for the Women.
Direction-specific van der Waals attraction between rutile TiO _{2} nanocrystals
Energy Technology Data Exchange (ETDEWEB)
Zhang, Xin; He, Yang; Sushko, Maria L.; Liu, Jia; Luo, Langli; De Yoreo, James J.; Mao, Scott X.; Wang, Chongmin; Rosso, Kevin M.
2017-04-27
Mutual lattice orientations dictate the types and magnitudes of forces between crystalline particles. When lattice polarizability is anisotropic, the van der Waals dispersion attraction can, in principle, contribute to this direction dependence. Here we report direct measurement of this attraction between rutile nanocrystals, as a function of their mutual orientation and surface hydration extent. At tens of nanometers of separation the attraction is weak and shows no dependence on azimuthal alignment nor surface hydration. At separations of approximately one hydration layer the attraction is strongly dependent on azimuthal alignment, and systematically decreases as intervening water density increases. Measured forces are in close agreement with predictions from Lifshitz theory, and show that dispersion forces are capable of generating a torque between particles interacting in solution and between grains in materials.
Attractive faces temporally modulate visual attention
Nakamura, Koyo; Kawabata, Hideaki
2014-01-01
Facial attractiveness is an important biological and social signal on social interaction. Recent research has demonstrated that an attractive face captures greater spatial attention than an unattractive face does. Little is known, however, about the temporal characteristics of visual attention for facial attractiveness. In this study, we investigated the temporal modulation of visual attention induced by facial attractiveness by using a rapid serial visual presentation. Fourteen male faces and two female faces were successively presented for 160 ms, respectively, and participants were asked to identify two female faces embedded among a series of multiple male distractor faces. Identification of a second female target (T2) was impaired when a first target (T1) was attractive compared to neutral or unattractive faces, at 320 ms stimulus onset asynchrony (SOA); identification was improved when T1 was attractive compared to unattractive faces at 640 ms SOA. These findings suggest that the spontaneous appraisal of facial attractiveness modulates temporal attention. PMID:24994994
Attractive faces temporally modulate visual attention
Directory of Open Access Journals (Sweden)
Koyo eNakamura
2014-06-01
Full Text Available Facial attractiveness is an important biological and social signal on social interaction. Recent research has demonstrated that an attractive face captures greater spatial attention than an unattractive face does. Little is known, however, about the temporal characteristics of visual attention for facial attractiveness. In this study, we investigated the temporal modulation of visual attention induced by facial attractiveness by using a rapid serial visual presentation (RSVP. Fourteen male faces and two female faces were successively presented for 160 ms respectively, and participants were asked to identify two female faces embedded among a series of multiple male distractor faces. Identification of a second female target (T2 was impaired when a first target (T1 was attractive compared to neutral or unattractive faces, at 320 ms SOA; identification was improved when T1 was attractive compared to unattractive faces at 640 ms SOA. These findings suggest that the spontaneous appraisal of facial attractiveness modulates temporal attention.
Romantic attraction and adolescent smoking trajectories.
Pollard, Michael S; Tucker, Joan S; Green, Harold D; Kennedy, David P; Go, Myong-Hyun
2011-12-01
Research on sexual orientation and substance use has established that lesbian, gay, and bisexual (LGB) individuals are more likely to smoke than heterosexuals. This analysis furthers the examination of smoking behaviors across sexual orientation groups by describing how same- and opposite-sex romantic attraction, and changes in romantic attraction, are associated with distinct six-year developmental trajectories of smoking. The National Longitudinal Study of Adolescent Health dataset is used to test our hypotheses. Multinomial logistic regressions predicting smoking trajectory membership as a function of romantic attraction were separately estimated for men and women. Romantic attraction effects were found only for women. The change from self-reported heterosexual attraction to lesbian or bisexual attraction was more predictive of higher smoking trajectories than was a consistent lesbian or bisexual attraction, with potentially important differences between the smoking patterns of these two groups. Copyright © 2011 Elsevier Ltd. All rights reserved.
Neutron matter properties using generalized Skyrme force
International Nuclear Information System (INIS)
Mansour, H.M.M.; Ramadan, Kh.A.
2002-01-01
The generalized Skyrme potential is used to calculate the properties of neutron matter in the form of the Thomas–Fermi model. The binding energy per particle, spin symmetry energy, free energy, pressure, entropy, sound velocity and magnetic susceptibility are calculated as a function of density ρ. The results are comparable with those obtained by Friedman and Pandharipande, who used the Urbana v 14 potential plus an effective repulsive three-body force. (author)
Poincaré, Henri
2017-01-01
Here is an accurate and readable translation of a seminal article by Henri Poincaré that is a classic in the study of dynamical systems popularly called chaos theory. In an effort to understand the stability of orbits in the solar system, Poincaré applied a Hamiltonian formulation to the equations of planetary motion and studied these differential equations in the limited case of three bodies to arrive at properties of the equations’ solutions, such as orbital resonances and horseshoe orbits. Poincaré wrote for professional mathematicians and astronomers interested in celestial mechanics and differential equations. Contemporary historians of math or science and researchers in dynamical systems and planetary motion with an interest in the origin or history of their field will find his work fascinating. .
International Nuclear Information System (INIS)
Chang, J.S.; Baldwin, A.C.; Golden, D.M.
1979-01-01
A realistic assessment of the potential depletion of stratospheric ozone due to manmade emissions requires a knowledge of the sources and sinks of the potential threat. The reactions ClO + NO 2 + M yield products and Cl + NO 2 + M yield products are of interest because they represent possible sink mechanism for both odd chlorine and odd nitrogen species. In this paper, the Troe method (1977) is used to calculate the low-pressure limit rate constants of the above three-body reactions. The result for the Cl + NO 2 + M reaction is found to be in excellent agreement with the experimental finding of Niki et al. (1978), where both nitryl chloride and chlorine nitrate are products of the cited reaction. An explanation is proposed to account for apparent discrepancy between the measured rate constants for ClO + NO 2 + M in the forward and reverse directions. Stratospheric implications are also discussed
The attractive lip: A photomorphometric analysis.
Penna, V; Fricke, A; Iblher, N; Eisenhardt, S U; Stark, G B
2015-07-01
Throughout literature, there are different parameters defining the ideal shape of the lip and lower third of the face. This study was conducted to clarify what it is that makes lips attractive - and whether there are gender-related differences of an attractive lip and lower third of the face. Pictures of the lip and chin region of 176 patients were photographed in a standardised way and evaluated by 250 voluntary judges through an internet presentation by means of an analogue Likert scaling system. We found a significant higher ratio of upper vermillion height/mouth-nose distance in frontal-view images of attractive compared to unattractive female (p attractive than in unattractive female (p attractive compared to unattractive female perioral regions (p attractive female lip and chin regions showed a wider mentolabial angle compared to unattractive female lip and chin regions (p attractive female perioral regions showed a higher ratio of lower vermillion height/chin-mouth distance (p attractive male perioral regions (p attractivity of female and male individuals and prove that there are gender-related differences in form and shape of an attractive lower third of the face. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Cole, Daniel J; Payne, Mike C; Csányi, Gábor; Spearing, S Mark; Colombi Ciacchi, Lucio
2007-11-28
We have developed a classical two- and three-body interaction potential to simulate the hydroxylated, natively oxidized Si surface in contact with water solutions, based on the combination and extension of the Stillinger-Weber potential and of a potential originally developed to simulate SiO(2) polymorphs. The potential parameters are chosen to reproduce the structure, charge distribution, tensile surface stress, and interactions with single water molecules of a natively oxidized Si surface model previously obtained by means of accurate density functional theory simulations. We have applied the potential to the case of hydrophilic silicon wafer bonding at room temperature, revealing maximum room temperature work of adhesion values for natively oxidized and amorphous silica surfaces of 97 and 90 mJm(2), respectively, at a water adsorption coverage of approximately 1 ML. The difference arises from the stronger interaction of the natively oxidized surface with liquid water, resulting in a higher heat of immersion (203 vs 166 mJm(2)), and may be explained in terms of the more pronounced water structuring close to the surface in alternating layers of larger and smaller densities with respect to the liquid bulk. The computed force-displacement bonding curves may be a useful input for cohesive zone models where both the topographic details of the surfaces and the dependence of the attractive force on the initial surface separation and wetting can be taken into account.
Ailing voters advance attractive congressional candidates.
Zebrowitz, Leslie A; Franklin, Robert G; Palumbo, Rocco
2015-01-06
Among many benefits of facial attractiveness, there is evidence that more attractive politicians are more likely to be elected. Recent research found this effect to be most pronounced in congressional districts with high disease threat-a result attributed to an adaptive disease avoidance mechanism, whereby the association of low attractiveness with poor health is particularly worrisome to voters who feel vulnerable to disease. We provided a more direct test of this explanation by examining the effects of individuals' own health and age. Supporting a disease avoidance mechanism, less healthy participants showed a stronger preference for more attractive contenders in U.S. Senate races than their healthier peers, and this effect was stronger for older participants, who were generally less healthy than younger participants. Stronger effects of health for older participants partly reflected the absence of positive bias toward attractive candidates among the healthiest, suggesting that healthy older adults may be unconcerned about disease threat or sufficiently wise to ignore attractiveness.
Facial aesthetics: babies prefer attractiveness to symmetry.
Samuels, Curtis A; Butterworth, George; Roberts, Tony; Graupner, Lida; Hole, Graham
2013-01-01
The visual preferences of human infants for faces that varied in their attractiveness and in their symmetry about the midline were explored. The aim was to establish whether infants' visual preference for attractive faces may be mediated by the vertical symmetry of the face. Chimeric faces, made from photographs of attractive and unattractive female faces, were produced by computer graphics. Babies looked longer at normal and at chimeric attractive faces than at normal and at chimeric unattractive faces. There were no developmental differences between the younger and older infants: all preferred to look at the attractive faces. Infants as young as 4 months showed similarity with adults in the 'aesthetic perception' of attractiveness and this preference was not based on the vertical symmetry of the face.
Effects of physical attractiveness on political beliefs.
Peterson, Rolfe Daus; Palmer, Carl L
2017-01-01
Physical attractiveness is an important social factor in our daily interactions. Scholars in social psychology provide evidence that attractiveness stereotypes and the "halo effect" are prominent in affecting the traits we attribute to others. However, the interest in attractiveness has not directly filtered down to questions of political behavior beyond candidates and elites. Utilizing measures of attractiveness across multiple surveys, we examine the relationship between attractiveness and political beliefs. Controlling for socioeconomic status, we find that more attractive individuals are more likely to report higher levels of political efficacy, identify as conservative, and identify as Republican. These findings suggest an additional mechanism for political socialization that has further implications for understanding how the body intertwines with the social nature of politics.
Attractiveness and Cooperation in Social Exchange
Directory of Open Access Journals (Sweden)
Chisato Takahashi
2006-01-01
Full Text Available We tested the hypothesis that physically more attractive men are less likely to cooperate in social exchange than less attractive men, while physical attractiveness has no effect on women's tendency toward cooperation, with four different experimental games (Prisoner's Dilemma with 99 players, Allocator Choice with 77 players, Faith with 16 players, and Trust with 21 players. Pictures of the game players were taken after they participated in one of the four games, and those pictures were presented to another set of participants (85 raters in Study 1 and 2, 36 raters in Study 3 for attractiveness ratings. Both male and female raters who were unaware of the photographed game players' actual behavior in the game judged the faces of male defectors (who defected in one of the four games to be more attractive than those of male cooperators, but they did not give differential attractiveness ratings to female defectors and female cooperators.
Investment Attractiveness of Food Industries in Ukraine
L. О.
2017-01-01
Effective investment is a factor for long-term company development. As enhancement of investment attractiveness is a required condition for economic growth and improvement of living standards, it needs to be on the agenda at government and company level. The article’s objective is to study investment attractiveness of food industries in Ukraine over 2012–2015. Investment attractiveness of food industries can be measured by indicators of liquidity, financial sustainability, and profit rate...
International Nuclear Information System (INIS)
Sutton, C.
1989-01-01
Inside the atom, particles interact through two forces which are never felt in the everyday world. But they may hold the key to the Universe. These ideas on subatomic forces are discussed with respect to the strong force, the electromagnetic force and the electroweak force. (author)
Positive illusions about one's partner's physical attractiveness.
Barelds-Dijkstra, Pieternel; Barelds, Dick P H
2008-03-01
This study examined couples' ratings of self and partner physical attractiveness. On the basis of the theory of positive illusions, it was expected that individuals would rate their partners as more attractive than their partners would rate themselves. Both members of 93 heterosexual couples, with a mean relationship length of about 14 years, provided ratings of both their own and their partner's physical attractiveness. Results support the theory that individuals hold positive illusions about their partner's physical attractiveness. Implications of these results in terms of relationship-enhancing biases are discussed.
Directory of Open Access Journals (Sweden)
E. A. Chaplygin
2018-04-01
Full Text Available Purpose. To carry out numerical estimates of currents and forces in the investigated inductor system with an attractive screen (ISAS and determine the effectiveness of the force attraction. Methodology. The calculated relationships and graphical constructions were obtained using the initial data of the system: induced current in the screen and sheet metal; the distributed force of attraction (Ampère force; the repulsive force acting on the sheet metal (Lorentz force; amplitude values of the force of attraction and repulsion; phase dependence of the force of attraction, the repulsive force and the total resulting force. Results. The results of calculations in the form of graphical dependencies of electrodynamic processes in the region under the conductors of a rectangular solenoid of inductor system with an attracting screen are presented. The graphs of forces and currents in region of dent are obtained. In the paper the analysis of electrodynamics processes for whole area under the winding of inductor system with an attractive screen is shown. The flowing this processes in the region of dent a given geometry is presented. Originality. The considered inductor system with an attractive screen and a rectangular solenoid is improved, in comparison with the previous developed ISAS. It has a working area under the lines of parallel conductors in the cross section of a rectangular solenoid, and this allows to place a predetermined portion of the sheet metal anywhere within the working region. Comparison of the indicators of electrodynamics processes in the considered variants of calculation shows an approximate growth of almost 1.5 times the power indicators in the area of the accepted dent in comparison with similar values for the entire area under the winding of the ISAS. Practical value. The results obtained are important for the practice of real estimates of the excited forces of attraction. With a decrease in the dent, the amplitude of the
Liquid drops attract or repel by the inverted Cheerios effect.
Karpitschka, Stefan; Pandey, Anupam; Lubbers, Luuk A; Weijs, Joost H; Botto, Lorenzo; Das, Siddhartha; Andreotti, Bruno; Snoeijer, Jacco H
2016-07-05
Solid particles floating at a liquid interface exhibit a long-ranged attraction mediated by surface tension. In the absence of bulk elasticity, this is the dominant lateral interaction of mechanical origin. Here, we show that an analogous long-range interaction occurs between adjacent droplets on solid substrates, which crucially relies on a combination of capillarity and bulk elasticity. We experimentally observe the interaction between droplets on soft gels and provide a theoretical framework that quantitatively predicts the interaction force between the droplets. Remarkably, we find that, although on thick substrates the interaction is purely attractive and leads to drop-drop coalescence, for relatively thin substrates a short-range repulsion occurs, which prevents the two drops from coming into direct contact. This versatile interaction is the liquid-on-solid analog of the "Cheerios effect." The effect will strongly influence the condensation and coarsening of drops on soft polymer films, and has potential implications for colloidal assembly and mechanobiology.
Investment Attractiveness of Food Industries in Ukraine
Directory of Open Access Journals (Sweden)
L. О.
2017-02-01
Full Text Available Effective investment is a factor for long-term company development. As enhancement of investment attractiveness is a required condition for economic growth and improvement of living standards, it needs to be on the agenda at government and company level. The article’s objective is to study investment attractiveness of food industries in Ukraine over 2012–2015. Investment attractiveness of food industries can be measured by indicators of liquidity, financial sustainability, and profit rate. Basically, food industries in Ukraine are attractive for investment, which is demonstrated by assessment of the financial indicators. The investment attractiveness worsened slightly in 2015 compared with 2014. The essential problems faced by food industries are shortage of internal funds and negative profit rate of all the activities, assets and own capital. Official statistical data and software package SPSS are used to build the dendrogram, allowing for dividing food industries by level of investment attractiveness into three groups: industries with high, medium and low level of investment attractiveness. It is found that meat industry is the one with the highest level of investment attractiveness. Also, investors should look positively at food-canning industry, oil and animal fat industry, flour-milling industry, starch and starch products industry, and other foods industry.
Sexual Attraction and Harassment: Management's New Problems.
Driscoll, Jeanne Bosson
1981-01-01
Both sexual attraction and harassment must be dealt with if men and women are to develop truly productive working relationships. Key issues include policies on sexual attraction and harassment, availability of professional resources on the subjects, training, and the role of personnel specialists. (CT)
Interpersonal Attraction in the Counseling Relationship.
Wachowiak, Dale; Diaz, Sandra
Murstein's Stimulus-Value-Role theory of dyadic relationships, in which attraction depends on the exchange value of the assets and liabilities each person brings to the situation, is employed as a foundation for this review of the literature on interpersonal attraction in the counseling relationship. A three-stage model, accounting for both…
The influence of facial attractiveness on imitation
Leeuwen, M.L. van; Veling, H.P.; Baaren, R.B. van; Dijksterhuis, A.J.
2009-01-01
People judge, evaluate, and treat attractive people better than moderately attractive or unattractive people [Langlois, J. H., Kalakanis, L., Rubenstein, A. J., Larson, A., Hallam, M., & Smoot, M. (2000). Maxims or myths of beauty? A meta-analytic and theoretical review. Psychological Bulletin, 126,
Positive illusions about one's partner's physical attractiveness
Barelds-Dijkstra, Pieternel; Barelds, Dick P. H.
This study examined couples' ratings of self and partner physical attractiveness. On the basis of the theory of positive illusions, it was expected that individuals would rate their partners as more attractive than their partners would rate themselves. Both members of 93 heterosexual couples, with a
Body Image, Physical Attractiveness, and Depression.
Noles, Steven W.; And Others
1985-01-01
Examined the relationship between body image, global self-concept, and depression. Men and women (N=224) completed questionnaires and were videotaped and objectively rated on attractiveness. Results indicated that depressed subjects were less satisfied with their bodies and saw themselves as less physically attractive than was reported by…
Electron attraction mediated by Coulomb repulsion.
Hamo, A; Benyamini, A; Shapir, I; Khivrich, I; Waissman, J; Kaasbjerg, K; Oreg, Y; von Oppen, F; Ilani, S
2016-07-21
One of the defining properties of electrons is their mutual Coulomb repulsion. However, in solids this basic property may change; for example, in superconductors, the coupling of electrons to lattice vibrations makes the electrons attract one another, leading to the formation of bound pairs. Fifty years ago it was proposed that electrons can be made attractive even when all of the degrees of freedom in the solid are electronic, by exploiting their repulsion from other electrons. This attraction mechanism, termed 'excitonic', promised to achieve stronger and more exotic superconductivity. Yet, despite an extensive search, experimental evidence for excitonic attraction has yet to be found. Here we demonstrate this attraction by constructing, from the bottom up, the fundamental building block of the excitonic mechanism. Our experiments are based on quantum devices made from pristine carbon nanotubes, combined with cryogenic precision manipulation. Using this platform, we demonstrate that two electrons can be made to attract each other using an independent electronic system as the 'glue' that mediates attraction. Owing to its tunability, our system offers insights into the underlying physics, such as the dependence of the emergent attraction on the underlying repulsion, and the origin of the pairing energy. We also demonstrate transport signatures of excitonic pairing. This experimental demonstration of excitonic pairing paves the way for the design of exotic states of matter.
Branner-Hubbard motions and attracting dynamics
DEFF Research Database (Denmark)
Petersen, Carsten Lunde; Tan, Lei
We introduce the new notion an aatracting dynamics, which is related to polynomial-likke mappings. Also we review the Branner-Hubbard motion and study its action on attracting dynamics.......We introduce the new notion an aatracting dynamics, which is related to polynomial-likke mappings. Also we review the Branner-Hubbard motion and study its action on attracting dynamics....
Bose-Einstein atoms in atomic traps with predominantly attractive two-body interactions
International Nuclear Information System (INIS)
Hussein, M.S.; Vorov, O.K.
2002-01-01
Using the Perron-Frobenius theorem, we prove that the results by Wilkin, Gunn, and Smith [Phys. Rev. Lett. 80, 2265 (1998)] for the ground states at angular momentum L of N harmonically trapped Bose atoms, interacting via weak attractive δ 2 (r) forces, are valid for a broad class of predominantly attractive interactions V(r), not necessarily attractive for any r. This class is described by sufficient conditions on the two-body matrix elements of the potential V(r). It includes, in particular, the Gaussian attraction of arbitrary radius, -1/r-Coulomb and log(r)-Coulomb forces, as well as all the short-range interactions satisfying inequality ∫d 2 r-vectorV(r)<0. In the precollapse regime, the angular momentum L is concentrated in the collective 'center-of-mass' mode, and there is no condensation at high L
Baalouch, Marouen
Studies of charmless three-body decays of the neutral B mesons with a K0S in the final state are presented in this thesis. The analyses are performed with the full statistics recorded by the LHCb spectrometer during the Run I of the LHC. The amplitude analysis of the decay B0→K0Sπ+π− represents the main part of this thesis analysis. A time-integrated untagged Dalitz-Plot analysis of the decay is performed. The fit fractions of the quasi-two-body decays are obtained. Likewise, the direct CP asymmetries of the quasi-two-body decays B0→K*+(892)π−, B0→K0*+(1430)π−, B0→K2*+(1430)π− and B0→f0(980)K0S are obtained. The largest sensitivity is obtained for ACP (B0→K*+(892)π−). This measurement is the first observation of the CP asymmetry with a significance larger then five standard deviations. The measurement is in agreement with the world average, with an improved precision.
Oryu, S; Yamashita, H; Nakazawa, M; Kamada, H
2000-01-01
The hypernucleus subLAMBDA sup 9 Be is investigated in an alpha-alpha-LAMBDA three-body model using the Faddeev formalism. We use an alpha-alpha interaction in which the Pauli-forbidden states are correctly taken into account and we employ some phenomenological potentials between the alpha and LAMBDA particles. We obtained two bound states for J suppi = 1/2 sup + and 3/2 sup + , and three resonance states of (3/2) sub 1 sup - , (3/2) sub 2 sup - , (3/2) sub 3 sup -. We studied the properties of these states by calculating the components and the expectation values of the potential for each partial wave. It is found that a few channels dominate in the 1/2 sup + and 3/2 sup + states, so that the alpha-clusters or the sup 8 Be core are still alive in the nucleus. In a case were the two alpha particles are fixed on an axis the contour plots of the distribution of the LAMBDA particle are shown. With the assistence of these plots one can visually understand that some of them are shell-model-like states while others ...
Rodrigues Cavalcante, Ana Barbara; Joram, Christian
In the first part of the thesis, we present studies on three-body charmless $B^\\pm$ decays. The analysis is performed using LHCb dataset from proton-proton collisions at the centre-of-mass energy of 7 TeV and 8 TeV collected in 2011 and 2012, respectively, corresponding to an integrated luminosity of 3.1 fb$^{-1}$. We measured the inclusive $CP$ asymmetry of the four channels: $B^\\pm\\to K^\\pm\\pi^+\\pi^-$, $B^\\pm \\to K^\\pm K^+ K^-$, $B^\\pm \\to \\pi^\\pm\\pi^+\\pi^-$ and $B^\\pm\\to \\pi^\\pm K^+ K^-$. $CP$ asymmetries were also studied along the phase space. The second part of this thesis is devoted to my contribution to the LHCb SciFi Tracker, a detector made of scintillating fibres. It presents the experimental setups used to characterise the scintillating fibres which need to meet specific requirements to be able to operate under the running conditions foreseen for the LHCb upgrade. In addition, we discuss the results on the development of fibres made of a new class of scintillating material denominated as Nanostruc...
The contribution of the electrostatic proximity force to atomic force microscopy with insulators
International Nuclear Information System (INIS)
Stanley Czarnecki, W.; Schein, L.B.
2005-01-01
Measurements, using atomic force microscopy, of the force and force derivative on a charged insulating micron sized sphere as a function of gap between the sphere and a conductive plane have revealed attractive forces at finite gaps that are larger than predicted by either van der Waals or conventional electrostatic forces. We suggest that these observations may be due to an electrostatic force that we have identified theoretically and call the proximity force. This proximity force is due to the discrete charges on the surface of the sphere in close proximity to the plane
The contribution of the electrostatic proximity force to atomic force microscopy with insulators
Energy Technology Data Exchange (ETDEWEB)
Stanley Czarnecki, W. [Aetas Technology Corporation, P.O. Box 53398, Irvine, CA 92619-3398 (United States); IBM Corporation, 5600 Cottle Rd., Building 13, San Jose, CA 95193 (United States); Schein, L.B. [Aetas Technology Corporation, P.O. Box 53398, Irvine, CA 92619-3398 (United States)]. E-mail: schein@prodigy.net
2005-05-16
Measurements, using atomic force microscopy, of the force and force derivative on a charged insulating micron sized sphere as a function of gap between the sphere and a conductive plane have revealed attractive forces at finite gaps that are larger than predicted by either van der Waals or conventional electrostatic forces. We suggest that these observations may be due to an electrostatic force that we have identified theoretically and call the proximity force. This proximity force is due to the discrete charges on the surface of the sphere in close proximity to the plane.
The Relationship of Interpersonal Attraction and Attraction to Group in a Growth Group Setting.
Evans, Nancy J.
1984-01-01
Investigated the relationship of interpersonal attraction and attraction to groups. Students (N=56) participating in growth groups completed the Group Attitude Scale and individual rating scales early, midway, and late in the group. Data indicated an increasing relationship between interpersonal and group attraction throughout the life of the…
The Putative Son's Attractiveness Alters the Perceived Attractiveness of the Putative Father.
Prokop, Pavol
2015-08-01
A body of literature has investigated female mate choice in the pre-mating context (pre-mating sexual selection). Humans, however, are long-living mammals forming pair-bonds which sequentially produce offspring. Post-mating evaluations of a partner's attractiveness may thus significantly influence the reproductive success of men and women. I tested herein the theory that the attractiveness of putative sons provides extra information about the genetic quality of fathers, thereby influencing fathers' attractiveness across three studies. As predicted, facially attractive boys were more frequently attributed to attractive putative fathers and vice versa (Study 1). Furthermore, priming with an attractive putative son increased the attractiveness of the putative father with the reverse being true for unattractive putative sons. When putative fathers were presented as stepfathers, the effect of the boy's attractiveness on the stepfather's attractiveness was lower and less consistent (Study 2). This suggests that the presence of an attractive boy has the strongest effect on the perceived attractiveness of putative fathers rather than on non-fathers. The generalized effect of priming with beautiful non-human objects also exists, but its effect is much weaker compared with the effects of putative biological sons (Study 3). Overall, this study highlighted the importance of post-mating sexual selection in humans and suggests that the heritable attractive traits of men are also evaluated by females after mating and/or may be used by females in mate poaching.
Differences between Caucasian and Asian attractive faces.
Rhee, S C
2018-02-01
There are discrepancies between the public's current beauty desires and conventional theories and historical rules regarding facial beauty. This photogrammetric study aims to describe in detail mathematical differences in facial configuration between attractive Caucasian and attractive Asian faces. To analyse the structural differences between attractive Caucasian and attractive Asian faces, frontal face and lateral face views for each race were morphed; facial landmarks were defined, and the relative photographic pixel distances and angles were measured. Absolute values were acquired by arithmetic conversion for comparison. The data indicate that some conventional beliefs of facial attractiveness can be applied but others are no longer valid in explaining perspectives of beauty between Caucasians and Asians. Racial differences in the perceptions of attractive faces were evident. Common features as a phenomenon of global fusion in the perspectives on facial beauty were revealed. Beauty standards differ with race and ethnicity, and some conventional rules for ideal facial attractiveness were found to be inappropriate. We must reexamine old principles of facial beauty and continue to fundamentally question it according to its racial, cultural, and neuropsychological aspects. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Common views of potentially attractive fusion concepts
International Nuclear Information System (INIS)
Piet, S.J.
1986-01-01
Several innovative fusion concepts have recently been proposed with the intent of improving radically the attractiveness of fusion energy. Before their assessment is complete, however, the question of what constitutes an especially attractive fusion product should be examined from multiple viewpoints. The primary purpose of this paper is to examine views of potentially attractive fusion concepts from three perspectives, trying to determine commonalities. These viewpoints are (a) economics, (b) maintenance and reliability, and (c) safety and environment. The secondary purpose of the paper is to review some innovative concepts from these viewpoints
Studies of Three-Body Decay of B to J/ψηK and B(Bs to ηcπK*
Directory of Open Access Journals (Sweden)
Behnam Mohammadi
2014-01-01
Full Text Available We investigate the B0→J/ψηK0 and B+→J/ψηK+ decay by using the Dalitz plot analysis. As we know there are tree, penguin, emission, and emission-annihilation diagrams for these decay modes in the factorization approach. The transition matrix element is factorized into a B→ηK form factor multiplied by J/ψ decay constant and also a B→K form factor multiplied by J/ψη decay constant. According to QCD factorization approach and using the Dalitz plot analysis, we calculate the branching ratios of the B0→J/ψηK0 and B+→J/ψηK+ three-body decay in view of the η-η' mixing and obtain the value of the (9.22-1.47+2.67×10-5, while the experimental results of them are (8±4×10-5 and (10.8±3.3×10-5, respectively. In this research we also analyze the B(Bs→ηcπK* decay which is similar to the previous decay, but there is no experimental data for the last decay. Since for calculations of the B(Bs→ηcπK* decay we use assumptions of the B→J/ψηK decay, we hope that if this decay will be measured by the LHCb in the future, the experimental results will be in agreement with our calculations.
Direct measurement of sub-Debye-length attraction between oppositely charged surfaces.
Kampf, Nir; Ben-Yaakov, Dan; Andelman, David; Safran, S A; Klein, Jacob
2009-09-11
Using a surface force balance with fast video analysis, we have measured directly the attractive forces between oppositely charged solid surfaces (charge densities sigma(+), sigma(-)) across water over the entire range of interaction, in particular, at surface separations D below the Debye screening length lambda(S). At very low salt concentration we find a long-ranged attraction between the surfaces (onset ca. 100 nm), whose variation at D
Agthe, Maria; Spörrle, Matthias; Maner, Jon K
2011-08-01
Previous studies of organizational decision making demonstrate an abundance of positive biases directed toward highly attractive individuals. The current research, in contrast, suggests that when the person being evaluated is of the same sex as the evaluator, attractiveness hurts, rather than helps. Three experiments assessing evaluations of potential job candidates (Studies 1 and 3) and university applicants (Study 2) demonstrated positive biases toward highly attractive other-sex targets but negative biases toward highly attractive same-sex targets. This pattern was mediated by variability in participants' desire to interact with versus avoid the target individual (Studies 1 and 2) and was moderated by participants' level of self-esteem (Study 3); the derogation of attractive same-sex targets was not observed among people with high self-esteem. Findings demonstrate an important exception to the positive effects of attractiveness in organizational settings and suggest that negative responses to attractive same-sex targets stem from perceptions of self-threat.
The subtle attractions of dry vault storage
International Nuclear Information System (INIS)
Ealing, C.J.
1993-01-01
Utilities in the United States of America, Scotland and Hungary have all adopted dry vault technology in their plans for spent fuel storage. This article looks at what makes dry storage an attractive option. (author)
Integrating body movement into attractiveness research.
Fink, Bernhard; Weege, Bettina; Neave, Nick; Pham, Michael N; Shackelford, Todd K
2015-01-01
People judge attractiveness and make trait inferences from the physical appearance of others, and research reveals high agreement among observers making such judgments. Evolutionary psychologists have argued that interest in physical appearance and beauty reflects adaptations that motivate the search for desirable qualities in a potential partner. Although men more than women value the physical appearance of a partner, appearance universally affects social perception in both sexes. Most studies of attractiveness perceptions have focused on third party assessments of static representations of the face and body. Corroborating evidence suggests that body movement, such as dance, also conveys information about mate quality. Here we review evidence that dynamic cues (e.g., gait, dance) also influence perceptions of mate quality, including personality traits, strength, and overall attractiveness. We recommend that attractiveness research considers the informational value of body movement in addition to static cues, to present an integrated perspective on human social perception.
Social preferences based on sexual attractiveness
DEFF Research Database (Denmark)
Brask, Josefine Bohr; Croft, Darren P.; Thompson, Katharine
2012-01-01
influencing the decision-making of males to their advantage. We tested this hypothesis in the Trinidadian guppy (Poecilia reticulata), a species with high levels of male sexual harassment. First, we confirmed that non-receptive females were harassed less when they were paired with a more sexually attractive...... with females that are more sexually attractive than themselves and that they perform active partner choices based on this relative attractiveness. We propose that this strategy is likely to represent an important pathway by which females can construct social niches that influence the decision-making of others......Male sexual harassment of females is common across sexually reproducing species and can result in fitness costs to females. We hypothesized that females can reduce unwanted male attention by constructing a social niche where their female associates are more sexually attractive than themselves, thus...
Attracting and repelling in homogeneous signal processes
International Nuclear Information System (INIS)
Downarowicz, T; Grzegorek, P; Lacroix, Y
2010-01-01
Attracting and repelling are discussed on two levels: in abstract signal processes and in signal processes arising as returns to a fixed set in an ergodic dynamical system. In the first approach, among other things, we give three examples in which the sum of two Poisson (hence neutral—neither attracting nor repelling) processes comes out either neutral or attracting, or repelling, depending on how the two processes depend on each other. The main new result of the second type concerns so-called 'composite events' in the form of a union of all cylinders over blocks belonging to the δ-ball in the Hamming distance around a fixed block. We prove that in a typical ergodic nonperiodic process the majority of such 'composite events' reveal strong attracting. We discuss the practical interpretation of this result
Electrostatic attraction between overall neutral surfaces.
Adar, Ram M; Andelman, David; Diamant, Haim
2016-08-01
Two overall neutral surfaces with positively and negatively charged domains ("patches") have been shown in recent experiments to exhibit long-range attraction when immersed in an ionic solution. Motivated by the experiments, we calculate analytically the osmotic pressure between such surfaces within the Poisson-Boltzmann framework, using a variational principle for the surface-averaged free energy. The electrostatic potential, calculated beyond the linear Debye-Hückel theory, yields an overall attraction at large intersurface separations, over a wide range of the system's controlled length scales. In particular, the attraction is stronger and occurs at smaller separations for surface patches of larger size and charge density. In this large patch limit, we find that the attraction-repulsion crossover separation is inversely proportional to the square of the patch-charge density and to the Debye screening length.
Interpersonal attraction in buyer–supplier relationships
DEFF Research Database (Denmark)
Ellegaard, Chris
2012-01-01
The concept of attraction is not reserved for the study of interpersonal relationships between husband and wife, family members, or lifelong friends. On the contrary, it contains much potential as a variable describing interpersonal business exchange relationships. This potential has been noted...... by well-known industrial marketing scholars in the past, and recent theoretical advances have incorporated attraction to describe buyer– supplier exchange, although primarily at the interorganizational level of analysis. The in-depth understanding of interpersonal attraction between boundary spanners...... representing buying and supply companies has yet to be developed. By drawing on social psychology and social exchange literature, this paper attempts to fill some of this gap. It contributes by uncovering the elements and process of interpersonal attraction. Furthermore, propositions are formulated to guide...
MUSEUMS AS CULTURAL TOURISM ATTRACTIONS IN UBUD
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Ida Bagus Kade Subhiksu
2016-03-01
Full Text Available Recently, there has been a shift in the attributes of several museums in Ubud in order to attract more tourists to visit museums as cultural tourism attractions. Some museums have expanded their collections and add other attributes to complement their main collections, which as the potential to alter the idealism, functions, and roles of museums. Another challenge faced by museum operators is the development of other tourist attractions, such as the addition of tourism destination attributes in Ubud, which was initially known as tourism destinations that offered art and culture such as dance performances and museums, and now have expanded into yoga destination, adventure destination, and so on. Based on these factors, the problem statements in this research are formulated as follows: (1 How are museums as tourist attractions in Ubud area, from the perspective of operators? (2 How are museums as tourist attractions in Ubud area, from the perspective of visitors? (3 How is the relationship between museums and other tourism components when examined from the role of museums as cultural tourism attractions in Ubud area?. This research on museums was conducted in the Ubud area because Ubud has made museums as the cultural tourism attractions in the area, which include the Blanco Museum, Museum Puri Lukisan, Agung Rai Museum of Art (ARMA, the Rudana Museum, and Neka Art Museum. This research is based on the theories of museum management, marketing, and theories on cultural tourism attraction. The research involved the participation of 82 foreign visitors and 79 domestic visitors as respondents, in addition to five museum owners and two museum professionals as informants. The conclusion of this research are as follows: (1 From the perspective of museum operators, museums function as cultural tourism attractions, as sources of historical information, as the media for cultural preservation, and the actualization of the noble objective of the museum
Attractive and repulsive magnetic suspension systems overview
Cope, David B.; Fontana, Richard R.
1992-01-01
Magnetic suspension systems can be used in a wide variety of applications. The decision of whether to use an attractive or repulsive suspension system for a particular application is a fundamental one which must be made during the design process. As an aid to the designer, we compare and contrast attractive and repulsive magnetic suspension systems and indicate whether and under what conditions one or the other system is preferred.
Hydrodynamic attraction of swimming microorganisms by surfaces
Berke, Allison P.; Turner, Linda; Berg, Howard C.; Lauga, Eric
2008-01-01
Cells swimming in confined environments are attracted by surfaces. We measure the steady-state distribution of smooth-swimming bacteria (Escherichia coli) between two glass plates. In agreement with earlier studies, we find a strong increase of the cell concentration at the boundaries. We demonstrate theoretically that hydrodynamic interactions of the swimming cells with solid surfaces lead to their re-orientation in the direction parallel to the surfaces, as well as their attraction by the c...
Malaria mosquitoes attracted by fatal fungus.
Directory of Open Access Journals (Sweden)
Justin George
Full Text Available Insect-killing fungi such as Beauveria bassiana are being evaluated as possible active ingredients for use in novel biopesticides against mosquito vectors that transmit malaria. Fungal pathogens infect through contact and so applications of spores to surfaces such as walls, nets, or other resting sites provide possible routes to infect mosquitoes in and around domestic dwellings. However, some insects can detect and actively avoid fungal spores to reduce infection risk. If true for mosquitoes, such behavior could render the biopesticide approach ineffective. Here we find that the spores of B. bassiana are highly attractive to females of Anopheles stephensi, a major anopheline mosquito vector of human malaria in Asia. We further find that An. stephensi females are preferentially attracted to dead and dying caterpillars infected with B. bassiana, landing on them and subsequently becoming infected with the fungus. Females are also preferentially attracted to cloth sprayed with oil-formulated B. bassiana spores, with 95% of the attracted females becoming infected after a one-minute visit on the cloth. This is the first report of an insect being attracted to a lethal fungal pathogen. The exact mechanisms involved in this behavior remain unclear. Nonetheless, our results indicate that biopesticidal formulations comprising B. bassiana spores will be conducive to attraction and on-source visitation by malaria vectors.
Divine proportions in attractive and nonattractive faces.
Pancherz, Hans; Knapp, Verena; Erbe, Christina; Heiss, Anja Melina
2010-01-01
To test Ricketts' 1982 hypothesis that facial beauty is measurable by comparing attractive and nonattractive faces of females and males with respect to the presence of the divine proportions. The analysis of frontal view facial photos of 90 cover models (50 females, 40 males) from famous fashion magazines and of 34 attractive (29 females, five males) and 34 nonattractive (13 females, 21 males) persons selected from a group of former orthodontic patients was carried out in this study. Based on Ricketts' method, five transverse and seven vertical facial reference distances were measured and compared with the corresponding calculated divine distances expressed in phi-relationships (f=1.618). Furthermore, transverse and vertical facial disproportion indices were created. For both the models and patients, all the reference distances varied largely from respective divine values. The average deviations ranged from 0.3% to 7.8% in the female groups of models and attractive patients with no difference between them. In the male groups of models and attractive patients, the average deviations ranged from 0.2% to 11.2%. When comparing attractive and nonattractive female, as well as male, patients, deviations from the divine values for all variables were larger in the nonattractive sample. Attractive individuals have facial proportions closer to the divine values than nonattractive ones. In accordance with the hypothesis of Ricketts, facial beauty is measurable to some degree. COPYRIGHT © 2009 BY QUINTESSENCE PUBLISHING CO, INC.
Social attraction mediated by fruit flies' microbiome.
Venu, Isvarya; Durisko, Zachary; Xu, Jianping; Dukas, Reuven
2014-04-15
Larval and adult fruit flies are attracted to volatiles emanating from food substrates that have been occupied by larvae. We tested whether such volatiles are emitted by the larval gut bacteria by conducting tests under bacteria-free (axenic) conditions. We also tested attraction to two bacteria species, Lactobacillus brevis, which we cultured from larvae in our lab, and L. plantarum, a common constituent of fruit flies' microbiome in other laboratory populations and in wild fruit flies. Neither larvae nor adults showed attraction to axenic food that had been occupied by axenic larvae, but both showed the previously reported attraction to standard food that had been occupied by larvae with an intact microbiome. Larvae also showed significant attraction to volatiles from axenic food and larvae to which we added only either L. brevis or L. plantarum, and volatiles from L. brevis reared on its optimal growth medium. Controlled learning experiments indicated that larvae experienced with both standard and axenic used food do not perceive either as superior, while focal larvae experienced with simulated used food, which contains burrows, perceive it as superior to unused food. Our results suggest that flies rely on microbiome-derived volatiles for long-distance attraction to suitable food patches. Under natural settings, fruits often contain harmful fungi and bacteria, and both L. brevis and L. plantarum produce compounds that suppress the growth of some antagonistic fungi and bacteria. The larval microbiome volatiles may therefore lead prospective fruit flies towards substrates with a hospitable microbial environment.
Persepsi Wisatawan Terhadap Night Life Attraction
Directory of Open Access Journals (Sweden)
Hary Hermawan
2017-04-01
ABSTRACT Cabaret is a term performances of music, comedy, dance, drama, and other special mix of art perfomed by men who dressed in women (ladyboy on stage. Cabaret performances in Oyot Godhong Restaurant intended as new tourist attraction that is expected to increase the interest of tourists to visit Malioboro in Yogyakarta, especially to Oyot Godhong Restaurants. Based descriptive study shows that the characteristics travelers who viewed Kabaret show is very diverse, each of which has perceptions and motivations are different. Cabaret performances have qualified to become the cultural attractions are staged at night (night atraction in the city of Yogyakarta. Based on traveler perception indicates that the cabaret performances have beauty or aesthetics, uniqueness, and values that match the criteria criteria of the standard as a tourist attraction. Performances Cabaret in Oyot Godhong Restaurants able to increase the sale value. Oyot Godhong Restaurants previously only form of tourism facilities (amenities, but is now a restaurant that has a tourist attraction (atraction. Keywords: Cabaret show, night life attractions, tourism attraction, tourists perception, tourism marketing
Unconscious processing of facial attractiveness: invisible attractive faces orient visual attention.
Hung, Shao-Min; Nieh, Chih-Hsuan; Hsieh, Po-Jang
2016-11-16
Past research has proven human's extraordinary ability to extract information from a face in the blink of an eye, including its emotion, gaze direction, and attractiveness. However, it remains elusive whether facial attractiveness can be processed and influences our behaviors in the complete absence of conscious awareness. Here we demonstrate unconscious processing of facial attractiveness with three distinct approaches. In Experiment 1, the time taken for faces to break interocular suppression was measured. The results showed that attractive faces enjoyed the privilege of breaking suppression and reaching consciousness earlier. In Experiment 2, we further showed that attractive faces had lower visibility thresholds, again suggesting that facial attractiveness could be processed more easily to reach consciousness. Crucially, in Experiment 3, a significant decrease of accuracy on an orientation discrimination task subsequent to an invisible attractive face showed that attractive faces, albeit suppressed and invisible, still exerted an effect by orienting attention. Taken together, for the first time, we show that facial attractiveness can be processed in the complete absence of consciousness, and an unconscious attractive face is still capable of directing our attention.
Occupational Outlook Quarterly, 2012
2012-01-01
The labor force is the number of people ages 16 or older who are either working or looking for work. It does not include active-duty military personnel or the institutionalized population, such as prison inmates. Determining the size of the labor force is a way of determining how big the economy can get. The size of the labor force depends on two…
International Nuclear Information System (INIS)
Blokhintsev, L.D.; Igamov, S.B.; Nishonov, MM; Yarmukhamedov, R; Kamimura, M.
2003-01-01
The d(α, γ) 6 Li reaction is one of the sources of 6 Li production in the Big-Bang nuclear synthesis. At present extremely large uncertainties exist on this prediction mainly due to the absence of reliable directly measured cross section (or astrophysical S-factor, S(E)) at astrophysical relevant energies E, including E=0. As far theoretical calculation of the S(E) that have rather large spread. On the other hand, the d(α, γ) 6 Li reaction is predominantly of peripheral character at extremely low energies. Therefore the calculated S(E) at extremely low energies is mainly determined by the nuclear vertex constant (NVC) (or respective asymptotic normalization constant (ANC)) for the virtual decay 6 Li→α + d. Taking into account this circumstance we develop a method of calculation of the NVC for the virtual decay 6 Li→α + d for the subsequent application of the calculated one to the direct radiative capture d(α, γ) 6 Li cross - section (or astrophysical S-factor) calculation at extremely low energies E, including E=0. The developed method is based on the three-body Faddeev approach which is applied for the α-d scattering by using different forms of the NN- and αN-potentials. As a result the values of NVC and respective ANC for 6 Li→α + d virtual decay are obtained using two forms both for NN- and for αN-potential. They are the separable potentials with Yamaguchi type form factor and Paris potential with PEST 16 form factor for the NN- potential and Yamaguchi type form factor and Sack-Biedenharn-Breit potential for the αN- potential. A noticeable sensitivity to used forms of the NN- and αN- potential occurs both for the calculated NVC (or ANC) and astrophysical S- factor S(E) of the direct radiative capture d(α, γ) 6 Li reaction at extremely low energies E (≤100 keV), including the value E=0. The calculated S(E) have been obtained using the information about the NVC values. The obtained values of NVC and S(E) are compared with those of obtained
Van der Waals Forces and Photon-Less Effective Field Theory
International Nuclear Information System (INIS)
Arriola, E.R.
2011-01-01
In the ultra-cold regime Van der Waals forces between neutral atoms can be represented by short range effective interactions. We show that universal low energy scaling features of the underlying vdW long range force stemming from two photon exchange impose restrictions on an Effective Field Theory without explicit photons. The role of naively redundant operators, relevant to the definition of three body forces, is also analyzed. (author)
Quantum Statistics: Is there an effective fermion repulsion or boson attraction?
Mullin, W. J.; Blaylock, G.
2003-01-01
Physicists often claim that there is an effective repulsion between fermions, implied by the Pauli principle, and a corresponding effective attraction between bosons. We examine the origins of such exchange force ideas, the validity for them, and the areas where they are highly misleading. We propose that future explanations of quantum statistics should avoid the idea of a effective force completely and replace it with more appropriate physical insights, some of which are suggested here.
Assessment of perceived orthodontic appliance attractiveness.
Ziuchkovski, James P; Fields, Henry W; Johnston, William M; Lindsey, Delwin T
2008-04-01
To date, no studies have been published in the literature evaluating the esthetics of orthodontic appliances. The purpose of this study was to assess appliance variables, including appliance type, brand, wire, and ligature tie, for their relative attractiveness. Demographic factors were also evaluated. Appliances were placed in an adult, and digital images were captured, standardized, and incorporated into a computer-based survey. Subjects (n = 200) rated each image for attractiveness on a visual analog scale. The attractiveness ratings were analyzed by using factorial analysis of variance with repeated measures. Post-hoc testing was done with the Tukey-Kramer test (overall a appliances), ceramic, and all self-ligating/stainless steel appliances. No differences between brands in each appliance type were found. Ratings of some ceramic appliances were significantly affected by archwire and ligature tie, depending on several demographic interactions. Orthodontic appliance attractiveness varies by the following hierarchy of appliance types: alternative > ceramic > all stainless steel/self-ligating. Wire and tie selection can affect the appearance of ceramic appliances but have no impact on stainless steel or self-ligating appliances. Certain demographic factors have variable effects on attractiveness ratings.
Insulin signaling mediates sexual attractiveness in Drosophila.
Directory of Open Access Journals (Sweden)
Tsung-Han Kuo
Full Text Available Sexually attractive characteristics are often thought to reflect an individual's condition or reproductive potential, but the underlying molecular mechanisms through which they do so are generally unknown. Insulin/insulin-like growth factor signaling (IIS is known to modulate aging, reproduction, and stress resistance in several species and to contribute to variability of these traits in natural populations. Here we show that IIS determines sexual attractiveness in Drosophila through transcriptional regulation of genes involved in the production of cuticular hydrocarbons (CHC, many of which function as pheromones. Using traditional gas chromatography/mass spectrometry (GC/MS together with newly introduced laser desorption/ionization orthogonal time-of-flight mass spectrometry (LDI-MS we establish that CHC profiles are significantly affected by genetic manipulations that target IIS. Manipulations that reduce IIS also reduce attractiveness, while females with increased IIS are significantly more attractive than wild-type animals. IIS effects on attractiveness are mediated by changes in CHC profiles. Insulin signaling influences CHC through pathways that are likely independent of dFOXO and that may involve the nutrient-sensing Target of Rapamycin (TOR pathway. These results suggest that the activity of conserved molecular regulators of longevity and reproductive output may manifest in different species as external characteristics that are perceived as honest indicators of fitness potential.
Buhmann, Stefan Yoshi
2012-01-01
In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...
Particle attraction effects on the centrifugal casting and extrusion of alumina
International Nuclear Information System (INIS)
Schilling, C.H.; Bergstroem, L.; Ker, H.L.; Aksay, I.A.
1993-01-01
Interparticle attraction forces were empirically related to the centrifugal casting and extrusion behavior of flocculated alumina suspensions. Attractive forces were altered by two approaches: Salt flocculation, which entails regulating the electrical double-layer thickness through electrolyte additions; and screening of van der Waals attraction by steric interactions of surface-adsorbed fatty acids. Specimens produced by both compressibility at a critical maximum density that increased with decreasing interparticle attraction. Gradients in packing density during centrifugal casting were alleviated using both methods as long as spatial variations of the effective stress were within the low-compressibility range. We hypothesized that the reduced interparticle attraction in both methods may also raise the threshold packing density at which ductile-to-brittle transitions occur during plastic shear. Specimens prepared with oleic acid adlayers were highly plastic and easily extrudable at solids contents of up to 59 vol%, although salt-flocculated samples at 55 vol% density extruded at creeping flow rates that were insensitive to the applied pressure. Results suggested that particle rearrangement during shear, is a rate-limiting process, with an average relaxation time that is lowered by reducing interparticle attraction
Recognition bias and the physical attractiveness stereotype.
Rohner, Jean-Christophe; Rasmussen, Anders
2012-06-01
Previous studies have found a recognition bias for information consistent with the physical attractiveness stereotype (PAS), in which participants believe that they remember that attractive individuals have positive qualities and that unattractive individuals have negative qualities, regardless of what information actually occurred. The purpose of this research was to examine whether recognition bias for PAS congruent information is replicable and invariant across a variety of conditions (i.e. generalizable). The effects of nine different moderator variables were examined in two experiments. With a few exceptions, the effect of PAS congruence on recognition bias was independent of the moderator variables. The results suggest that the tendency to believe that one remembers information consistent with the physical attractiveness stereotype is a robust phenomenon. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.
Improved attractants for enhancing tsetse fly suppression
International Nuclear Information System (INIS)
2003-09-01
At the initiation of this co-ordinated research project (CRP), the available visually attractant devices and odours for entomological monitoring and for suppression of tsetse fly populations were not equally effective against all economically important tsetse fly species. For species like G. austeni, G. brevipalpis, G. swynnertoni and some species of the PALPALIS-group of tsetse flies no sufficiently effective combinations of visual or odour attractants were available for efficient suppression and standardized monitoring as part of an operational integrated intervention campaign against the tsetse and trypanosomosis (T and T) problem. The Co-ordinated Research Project on Improved Attractants for Enhancing the Efficiency of Tsetse Fly Suppression Operations and Barrier Systems used in Tsetse Control/Eradication Campaigns involved (a) the identification, synthesis and provision of candidate kairomones, their analogues and of dispensers; (b) laboratory screening of synthesised candidate kairomones through electrophysiological studies and wind tunnel experiments; (c) field tests of candidate kairomones alone or as part of odour blends, in combination with available and or new trap designs; and (d) analysis of hydrocarbons that influence tsetse sexual behaviour. The CRP accomplished several main objectives, namely: - The screening of new structurally related compounds, including specific stereoisomers, of known tsetse attractants resulted in the identification of several new candidate odour attractants with promising potential. - An efficient two-step synthetic method was developed for the pilot plant scale production of 3-n-propyphenol, synergistic tsetse kairomone component. - Electrophysiological experiments complemented with wind tunnel studies provided an efficient basis for the laboratory screening of candidate attractants prior to the initiation of laborious field tests. - New traps were identified and modifications of existing traps were tested for some species
Application of the three-body model to the reactions 6Li(3He,t 3He)3He and 6Li(3He,3He3He)3H
International Nuclear Information System (INIS)
Haftel, M.I.; Allas, R.G.; Beach, L.A.; Bondelid, R.O.; Petersen, E.L.; Slaus, I.; Lambert, J.M.; Treado, P.A.
1977-01-01
Experimental and theoretical cross sections are presented for the 6 Li( 3 He, 3 He 3 He) 3 H and 6 Li( 3 He,t 3 He) 3 He reactions for the symmetric angle pairs 20 0 -20 0 , 28.3 0 -28.3 0 , and 35 0 -35 0 . The theoretical cross sections are calculated in a three-body model where the trions (i.e., mass-3 nuclei) are treated as elementary particles with 6 Li being a 3 He- 3 H bound state. The trion-trion interaction is represented by S wave separable potentials with the breakup cross sections calculated with the tree-body Haftel-Ebenhoeh code. the Coulomb interaction is taken into account by fitting the separable potential parameters to the trion-trion scattering data and is included approximately in the breakup code. The experimental cross sections are compared with both the plane-wave impulse approximation and the three-body model predictions. The plane-wave impulse approximation predicts both the shapes and magnitudes poorly (10 to 20 times experiment). Without Coulomb corrections the three-body model gives good agreement with experiment for the shapes of the spectra with the magnitudes generally being about 40% of experiment for 6 Li( 3 He, 3 He 3 He) 3 H and about 80% for 6 Li( 3 He,t 3 He) 3 He. The Coulomb corrections improve the magnitudes predicted by the three-body model but not the shapes. It is observed that for these reactions S wave separable potentials describe the breakup data much better than they do the two-body trion-trion scattering data. This result should encourage further three-body treatment of these and similar reactions
Cavior, Norman; And Others
1975-01-01
Tenth and twelfth grade males and females who knew each other judged, within grade levels, their classmates on physical attractiveness (PA), perceived attitude similarity (PAS), and interpersonal attraction (IA). Regression analyses supported the hypotheses that PA and PAS are positively correlated. (Author)
Mathes, Eugene W.
1975-01-01
The "information availability model" of heterosexual attraction was tested by having subjects go on a series of five encounters. It was found that both physical attractiveness and the personality variable, anxiety, had early and continuous effects on liking. It was concluded the model is an inadequate explanation of heterosexual…
Nuclear reaction matrix and nuclear forces
International Nuclear Information System (INIS)
Nagata, Sinobu; Bando, Hiroharu; Akaishi, Yoshinori.
1979-01-01
An essentially exact method of solution is presented for the reaction- matrix (G-matrix) equation defined with the orthogonalized plane-wave intermediate spectrum for high-lying two-particle states. The accuracy is examined for introduced truncations and also in comparison with the Tsai-Kuo and Sauer methods. Properties of the G-matrix are discussed with emphasis on the relation with the saturation mechanism, especially overall saturation from light to heavy nuclei. Density and starting-energy dependences of the G-matrix are separately extracted and discussed. It is demonstrated that the triplet-even tensor component of the nuclear force is principally responsible for these dependences and hence for the saturation mechanism. In this context different nuclear potentials are used in the renormalized Brueckner calculation for energies of closed-shell nuclei in the harmonic oscillator basis. A semi-phenomenological ''two-body potential'' is devised so that it can reproduce the saturation energies and densities of nuclear matter and finite nuclei in the lowest-order Brueckner treatment. It is composed of a realistic N-N potential and two additional parts; one incorporates the three-body force effect and the other is assumed to embody higher-cluster correlations in G. The tensor component in the triplet-even state of this potential is enhanced by the three-body force effect. The G-matrix is represented in the effective local form and decomposed into central, LS and tensor components. (author)
Directory of Open Access Journals (Sweden)
Anton Schlechter
2014-11-01
Full Text Available Orientation: In order to attract knowledge workers and maintain a competitive advantage,it is necessary for organisations to understand how knowledge workers are attracted todifferent types and levels of financial rewards. Research purpose: This research investigated a set of financial reward elements (remuneration, employee benefits and variable pay to determine whether knowledgeworkers perceived them as attractive inducements when considering a job or position. Motivation for the study: In South Africa there is a shortage of talent, largely due to highrates of emigration of scarce skills (human capital. Financial rewards or inducementsare necessary to attract talent and it is essential to assess which of these rewards are mostsuccessful in this regard. Method: A 23 full-factorial experimental design (field experiment was used. The threefinancial reward elements (remuneration, employee benefits and variable pay weremanipulated in a fictitious job advertisement (each at two levels. Eight (2 × 2 × 2 = 8 differentversions of a job advertisement were used as a stimulus to determine the effect of financialreward elements on perceived job attractiveness. A questionnaire was used to measure howparticipants perceived the attractiveness of the job. A convenience sampling approach wasused. Different organisations throughout South Africa, as well as corporate members of the South African Reward Association, were asked to participate in the study. Respondents (n = 169 were randomly assigned to the various experimental conditions (i.e. one of the eightadvertisements. Data were analysed using descriptive statistics. A full-factorial analysis ofvariance was used to investigate if significant main effects could be found. Main findings: Participants considered high levels of remuneration, the inclusion ofbenefits and variable pay to be significant job attraction factors within a reward package. Remuneration was found to have the largest main effect on job
Attraction of nonlocal dark optical solitons
DEFF Research Database (Denmark)
Nikolov, Nikola Ivanov; Neshev, Dragomir; Krolikowski, Wieslaw
2004-01-01
We study the formation and interaction of spatial dark optical solitons in materials with a nonlocal nonlinear response. We show that unlike in local materials, where dark solitons typically repel, the nonlocal nonlinearity leads to a long-range attraction and formation of stable bound states...
Placemaking: Attracting and Retaining Today's Students
Knight, Brent
2016-01-01
Research suggests that the appearance of a college campus--both inside and out--is a significant criterion in college selection. As community colleges are finding it increasingly important to attract and retain students, placemaking is becoming an effective and efficient platform to support recruitment and retention. Placemaking is imagining and…
Attractive planar panelization using dynamic relaxation principles
Gauss, Florian; Teuffel, Patrick
2015-01-01
In the presented paper a new method is proposed to approximate a given NURBS surface with a PQ (Planar Quad) mesh. The desired mesh layout will be generated in then attracted to the target surface. The process iteratively pulls the mesh vertices towards the target surface and then planarizes the
Professional assessment of facial profile attractiveness.
Soh, Jen; Chew, Ming Tak; Wong, Hwee Bee
2005-08-01
The aim of this study was to compare the assessments of Chinese facial profile attractiveness by orthodontists and oral surgeons. The sample comprised 31 dental professionals (20 orthodontists, 11 oral surgeons) in an Asian community. Facial profile photographs and lateral cephalometric radiographs of 2 Chinese adults (1 man, 1 woman) with normal profiles, Class I incisor relationships, and Class I skeletal patterns were digitized. The digital images were modified by altering cephalometric skeletal and dental hard tissue Chinese normative values in increments of 2 standard deviations in the anteroposterior plane to obtain 7 facial profiles for each sex. The images were bimaxillary protrusion, protrusive mandible, retrusive mandible, normal profile (Class I incisor with Class I skeletal pattern), retrusive maxilla, protrusive maxilla, and bimaxillary retrusion. The Mann-Whitney U test was used to determine professional differences in assessment. Multiple regression analysis was performed with age, professional status, sex, and number of years in practice as independent variables. A strong correlation was found in the profile assessment between orthodontists and oral surgeons. Normal and bimaxillary retrusive Chinese male and female profiles were judged to be highly attractive by orthodontists and oral surgeons. Chinese male and female profiles with protrusive mandibles were judged the least attractive. There was a difference in professional opinion about the most attractive male profile (P profile and oral surgeons preferring a fuller normal Chinese profile. Sex of dental professionals and number of years in clinical practice were found to affect profile rankings.
Stereotyping Physical Attractiveness: A Sociocultural Perspective.
Dion, Karen K.; And Others
1990-01-01
Studies the tendency to stereotype physical attractiveness and identification in a collectivist culture using a group of 53 Chinese Canadian college students. Finds that introverts tended to be more prone to stereotyping than extroverts. Subjects with the highest cultural involvement were least prone to stereotyping with regard to social…
Basins of Attraction for Chimera States
DEFF Research Database (Denmark)
Martens, Erik Andreas; Panaggio, Mark; Abrams, Daniel
2016-01-01
Chimera states---curious symmetry-broken states in systems of identical coupled oscillators---typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we...
Male and Female Perception of Physical Attractiveness
Directory of Open Access Journals (Sweden)
Ray Garza
2016-02-01
Full Text Available Waist-to-hip ratio (WHR and breast size are morphological traits that are associated with female attractiveness. Previous studies using line drawings of women have shown that men across cultures rate low WHRs (0.6 and 0.7 as most attractive. In this study, we used additional viewing measurements (i.e., first fixation duration and visual regressions to measure visual attention and record how long participants first focused on the female body and whether they regressed back to an area of interest. Additionally, we manipulated skin tone to determine whether they preferred light- or dark-skinned women. In two eye tracking experiments, participants rated the attractiveness of female nude images varying in WHR (0.5–0.9, breast size, and skin tone. We measured first fixation duration, gaze duration, and total time. The overall results of both studies revealed that visual attention fell mostly on the face, the breasts, and the midriff of the female body, supporting the evolutionary view that reproductively relevant regions of the female body are important to female attractiveness. Because the stimuli varied in skin tone and the participants were mainly Hispanic of Mexican American descent, the findings from these studies also support a preference for low WHRs and reproductively relevant regions of the female body.
Cultured skin microbiota attracts malaria mosquitoes
Verhulst, N.O.; Beijleveld, H.; Knols, B.G.J.; Takken, W.; Schraa, G.; Bouwmeester, H.J.; Smallegange, R.C.
2009-01-01
Background - Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human
Cultured skin microbiota attracts malaria mosquitoes
Verhulst, Niels O.; Beijleveld, Hans; Knols, Bart Gj; Takken, Willem; Schraa, Gosse; Bouwmeester, Harro J.; Smallegange, Renate C.
2009-01-01
Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours.
Cultured skin microbiota attracts malaria mosquitoes
Verhulst, N.O.; Beijleveld, H.; Knols, B.G.J.; Takken, W.; Schraa, G.; Bouwmeester, H.J.; Smallegange, R.C.
2009-01-01
Background: Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human
Domain of attraction computation for tumor dynamics
Doban, A.I.; Lazar, M.
2014-01-01
In this paper we propose the use of rational Lyapunov functions to estimate the domain of attraction of the tumor dormancy equilibrium of immune cells-malignant cells interaction dynamics. A procedure for computing rational Lyapunov functions is worked out, with focus on obtaining a meaningful
Agreement Attraction in Comprehension: Representations and Processes
Wagers, Matthew W.; Lau, Ellen F.; Phillips, Colin
2009-01-01
Much work has demonstrated so-called attraction errors in the production of subject-verb agreement (e.g., "The key to the cabinets are on the table", [Bock, J. K., & Miller, C. A. (1991). "Broken agreement." "Cognitive Psychology, 23", 45-93]), in which a verb erroneously agrees with an intervening noun. Six self-paced reading experiments examined…
Synthesis: Part II, Land Use Attractiveness.
Pressman, Rob
This material includes student guide sheets, reference material, and tape script for the audio-tutorial unit on the Synthesis Unit, Land Use Attractiveness. An audiotape is used with the materials. The material is designed for use with Connecticut schools, but can be adapted to other localities. The unit is designed to build on skills and…
Ordinal Position, Approval Motivation, and Interpersonal Attraction
Nowicki, Stephen, Jr.
1971-01-01
Results of the study suggest that birth-order effects might be included within the wider framework of approval-dependency theory. Females tend to account for a significant share of birth-order effects. More particularly, firstborn females accounted for much of the differences in expressed attraction as well as need for social approval. (Author)
Attracting Preservice Teachers to Remote Locations
Young, Kenneth D.; Grainger, Peter; James, Dennis
2018-01-01
Teaching in rural/remote regions poses many challenges to teachers and is identified as a priority research area by the state government. Despite initiatives by the Queensland state government and university providers to solve the issue through various incentives designed to attract teachers, the problem remains significant. This research…
Facial Diversity and Infant Preferences for Attractive Faces.
Langlois, Judith H.; And Others
1991-01-01
Three studies examined infant preferences for attractive faces of White males, White females, Black females, and infants. Infants viewed pairs of faces rated for attractiveness by adults. Preferences for attractive faces were found for all facial types. (BC)
Nitrate analogs as attractants for soybean cyst nematode.
Hosoi, Akito; Katsuyama, Tsutomu; Sasaki, Yasuyuki; Kondo, Tatsuhiko; Yajima, Shunsuke; Ito, Shinsaku
2017-08-01
Soybean cyst nematode (SCN) Heterodera glycines Ichinohe, a plant parasite, is one of the most serious pests of soybean. In this paper, we report that SCN is attracted to nitrate and its analogs. We performed attraction assays to screen for novel attractants for SCN and found that nitrates were attractants for SCN and SCN recognized nitrate gradients. However, attraction of SCN to nitrates was not observed on agar containing nitrate. To further elucidate the attraction mechanism in SCN, we performed attraction assays using nitrate analogs ([Formula: see text], [Formula: see text], [Formula: see text]). SCN was attracted to all nitrate analogs; however, attraction of SCN to nitrate analogs was not observed on agar containing nitrate. In contrast, SCN was attracted to azuki root, irrespective of presence or absence of nitrate in agar media. Our results suggest that the attraction mechanisms differ between plant-derived attractant and nitrate.
Cultured skin microbiota attracts malaria mosquitoes
Directory of Open Access Journals (Sweden)
Takken Willem
2009-12-01
Full Text Available Abstract Background Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours. It is hypothesized that host attractiveness and selection of An. gambiae is affected by the species composition, density, and metabolic activity of the skin microbiota. A study is presented in which the production and constituency of volatile organic compounds (VOCs by human skin microbiota is examined and the behavioural responses of An. gambiae to VOCs from skin microbiota are investigated. Methods Blood agar plates incubated with skin microbiota from human feet or with a reference strain of Staphylococcus epidermidis were tested for their attractiveness to An. gambiae in olfactometer bioassays and indoor trapping experiments. Entrained air collected from blood agar plates incubated with natural skin microbiota or with S. epidermidis were analysed using GC-MS. A synthetic blend of the compounds identified was tested for its attractiveness to An. gambiae. Behavioural data were analysed by a χ2-test and GLM. GC-MS results were analysed by fitting an exponential regression line to test the effect of the concentration of bacteria. Results More An. gambiae were caught with blood agar plates incubated with skin bacteria than with sterile blood agar plates, with a significant effect of incubation time and dilution of the skin microbiota. When bacteria from the feet of four other volunteers were tested, similar effects were found. Fourteen putative attractants were found in the headspace of the skin bacteria. A synthetic blend of 10 of these was attractive to An. gambiae. Conclusions The discovery that volatiles produced by human skin microorganisms in vitro mediate An. gambiae host-seeking behaviour creates new opportunities for the
Physical attractiveness, romantic love, and equity restoration in dating relationships.
Critelli, J W; Waid, L R
1980-12-01
Measures of physical attractiveness, romantic love, and dominance were given to a sample of 123 dating couples. Contrary to expectation, attractive subjects were not loved more than those judged as less attractive. As suggested by equity theory, however, subjects who believed that their partners were the more attractive member of the dyad loved their partners more (p relationships (p attractive member. The results suggest that as the dating relationship progresses, the relative difference in attractiveness between partners may become a more important determinant of attraction than overall level of attractiveness.
Swarming and pattern formation due to selective attraction and repulsion.
Romanczuk, Pawel; Schimansky-Geier, Lutz
2012-12-06
We discuss the collective dynamics of self-propelled particles with selective attraction and repulsion interactions. Each particle, or individual, may respond differently to its neighbours depending on the sign of their relative velocity. Thus, it is able to distinguish approaching (coming closer) and retreating (moving away) individuals. This differentiation of the social response is motivated by the response to looming visual stimuli and may be seen as a generalization of the previously proposed escape and pursuit interactions motivated by empirical evidence for cannibalism as a driving force of collective migration in locusts and Mormon crickets. The model can account for different types of behaviour such as pure attraction, pure repulsion or escape and pursuit, depending on the values (signs) of the different response strengths. It provides, in the light of recent experimental results, an interesting alternative to previously proposed models of collective motion with an explicit velocity-alignment interaction. We discuss the derivation of a coarse-grained description of the system dynamics, which allows us to derive analytically the necessary condition for emergence of collective motion. Furthermore, we analyse systematically the onset of collective motion and clustering in numerical simulations of the model for varying interaction strengths. We show that collective motion arises only in a subregion of the parameter space, which is consistent with the analytical prediction and corresponds to an effective escape and/or pursuit response.
Hidden Attraction - The History and Mystery of Magnetism
Verschuur, Gerrit L.
1996-04-01
Long one of nature's most fascinating phenomena, magnetism was once the subject of many superstitions. Magnets were thought useful to thieves, effective as a love potion, and as a cure for gout or spasms. They could remove sorcery from women and put demons to flight and even reconcile married couples. It was said that a lodestone pickled in the salt of sucking fish had the power to attract gold. Today, these beliefs have been put aside, but magnetism is no less remarkable for our modern understanding of it. In Hidden Attraction , Gerrit L. Verschuur, a noted astronomer and National Book Award nominee for The Invisible Universe , traces the history of our fascination with magnetism, from the mystery and superstition that propelled the first alchemical experiments with lodestone, through the more tangible works of Faraday, Maxwell, Hertz and other great pioneers of magnetism (scientists responsible for the extraordinary advances in modern science and technology, including radio, the telephone, and computers, that characterize the twentieth century), to state-of-the-art theories that see magnetism as a basic force in the universe. Boasting many informative illustrations, this is an adventure of the mind, using the specific phenomenon of magnetism to show how we have moved from an era of superstitions to one in which the Theory of Everything looms on the horizon.
Hidden attraction the history and mystery of magnetism
Verschuur, Gerrit L
1996-01-01
Long one of nature''s most fascinating phenomena, magnetism was once the subject of many superstitions. Magnets were thought useful to thieves, effective as a love potion or as a cure for gout or spasms. They could remove sorcery from women and put demons to flight and even reconcile married couples. It was said that a lodestone pickled in the salt of sucking fish had the power to attract gold. Today, these beliefs have been put aside, but magnetism is no less remarkable for our modern understanding of it. In Hidden Attraction, Gerrit L. Verschuur, a noted astronomer and National Book Award nominee for The Invisible Universe, traces the history of our fascination with magnetism, from the first discovery of magnets in Greece, to state-of-the-art theories that see magnetism as a basic force in the universe. The book begins with the early debunking of superstitions by Peter Peregrinus (Pierre de Maricourt), whom Roger Bacon hailed as one of the world''s first experimental scientists (Perigrinus held that "experi...
1982-01-01
The different forces, together with a pictorial analogy of how the exchange of particles works. The table lists the relative strength of the couplings, the quanta associated with the force fields and the bodies or phenomena in which they have a dominant role.
Occupational Outlook Quarterly, 2010
2010-01-01
The labor force is the number of people aged 16 or older who are either working or looking for work. It does not include active-duty military personnel or institutionalized people, such as prison inmates. Quantifying this total supply of labor is a way of determining how big the economy can get. Labor force participation rates vary significantly…
Service Packages – Attractiveness Has Many Faces
Directory of Open Access Journals (Sweden)
Ilona Bondos
2016-01-01
Full Text Available This article is an attempt to identify the impact of the customer age (especially the Baby boomers generation and the X and the Y generation on the assessment of incentives to buy service package. Belonging to different age generations seems to be important for the effectiveness of service packages sales – the entrance by the consumers in subsequent phases of the life cycle is related to their perception of the market offer. The starting point for the empirical part of the article was to analyze the different average scores attractiveness of the ten packages service features (incentives to purchase. Then, using multidimensional scaling authors determined the similarity or dissimilarity data on a set of applied incentives to use service packages. Visible differences indicate a different perception of the attractiveness of packages representatives of the Baby boomer generation and Y generation. Managerial implications and directions for future research are discussed.
Manipulating bubbles with secondary Bjerknes forces
Energy Technology Data Exchange (ETDEWEB)
Lanoy, Maxime [Institut Langevin, ESPCI ParisTech, CNRS (UMR 7587), PSL Research University, 1 rue Jussieu, 75005 Paris (France); Laboratoire Matière et Systèmes Complexes, Université Paris-Diderot, CNRS (UMR 7057), 10 rue Alice Domon et Léonie Duquet, 75013 Paris (France); Derec, Caroline; Leroy, Valentin [Laboratoire Matière et Systèmes Complexes, Université Paris-Diderot, CNRS (UMR 7057), 10 rue Alice Domon et Léonie Duquet, 75013 Paris (France); Tourin, Arnaud [Institut Langevin, ESPCI ParisTech, CNRS (UMR 7587), PSL Research University, 1 rue Jussieu, 75005 Paris (France)
2015-11-23
Gas bubbles in a sound field are submitted to a radiative force, known as the secondary Bjerknes force. We propose an original experimental setup that allows us to investigate in detail this force between two bubbles, as a function of the sonication frequency, as well as the bubbles radii and distance. We report the observation of both attractive and, more interestingly, repulsive Bjerknes force, when the two bubbles are driven in antiphase. Our experiments show the importance of taking multiple scatterings into account, which leads to a strong acoustic coupling of the bubbles when their radii are similar. Our setup demonstrates the accuracy of secondary Bjerknes forces for attracting or repealing a bubble, and could lead to new acoustic tools for noncontact manipulation in microfluidic devices.
Manipulating bubbles with secondary Bjerknes forces
International Nuclear Information System (INIS)
Lanoy, Maxime; Derec, Caroline; Leroy, Valentin; Tourin, Arnaud
2015-01-01
Gas bubbles in a sound field are submitted to a radiative force, known as the secondary Bjerknes force. We propose an original experimental setup that allows us to investigate in detail this force between two bubbles, as a function of the sonication frequency, as well as the bubbles radii and distance. We report the observation of both attractive and, more interestingly, repulsive Bjerknes force, when the two bubbles are driven in antiphase. Our experiments show the importance of taking multiple scatterings into account, which leads to a strong acoustic coupling of the bubbles when their radii are similar. Our setup demonstrates the accuracy of secondary Bjerknes forces for attracting or repealing a bubble, and could lead to new acoustic tools for noncontact manipulation in microfluidic devices
The tourism attractiveness of Polish libraries
Miedzińska, Magdalena; Tanaś, Sławoj
2009-01-01
The aim of the article is to draw the reader's attention to the tourism attractiveness of renowned Polish libraries. These have attained a tourism function due to tourism exploration and penetration, but remain in the shadow of other Polish cultural assets. The article outlines the historical geography of Polish libraries, an analysis of tourism assets and an attempt to classify and catalogue libraries in Poland.