Numerical Methods in Configuration-Space A = 3, 4 Bound-State and Scattering Calculations

In this paper, a method has been developed to solve three-particle Faddeev equations in the configuration space making use of a series expansion in hyperspherical harmonics. The following parameters of the bound state of triton and helium-3 nuclei have been calculated: the binding energies, the weights of symmetric and mixed-symmetry components of the wave function, the magnetic moments, and the charge radii.

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ON ASYMPTOTICS OF THREE-BODY BOUND STATE RADIAL WAVE FUNCTIONS OF HALO NUCLEI NEAR THE HYPERANGLE φ~0 AND φ~π/2 IN THE CONFIGURATION SPACE AND THREE-BODY ASYMPTOTIC NORMALIZATION FACTORS FOR 6He NUCLEUS IN THE (n+n+α)-CHANNEL

International Journal of Modern Physics E ◽

10.1142/s0218301309013701 ◽

2009 ◽

Vol 18 (07) ◽

pp. 1561-1585 ◽

Cited By ~ 3

Author(s):

R. YARMUKHAMEDOV ◽

M. K. UBAYDULLAEVA

Keyword(s):

Wave Function ◽

Configuration Space ◽

Bound State ◽

Wave Functions ◽

Halo Nuclei ◽

Asymptotic Normalization ◽

Radial Wave ◽

Asymptotic Expressions ◽

Three Body ◽

Normalization Factors

Asymptotic expressions for the bound state radial partial wave functions of three-body (nnc) halo nuclei with two loosely bound valence neutrons (n) are obtained in explicit form, when the relative distance between two neutrons (r) tends to infinity and the relative distance between the center of mass of core (c) and two neutrons (ρ) is too small or vice versa. These asymptotic expressions contain a factor that can strongly influence the asymptotic values of the three-body radial wave function in the vicinity of the hyperangle of φ~0 except 0 (r→∞ and ρ is too small except 0) or φ~π/2 except π/2 (ρ→∞ and r is too small except 0) in the configuration space. The derived asymptotic forms are applied to the analysis of the asymptotic behavior of the three-body (nnα) wave function for 6He nucleus obtained by other authors on the basis of multicluster stochastic variational method using the two forms of the αN-potential. The ranges of r (or ρ) from the asymptotical regions are determined for which the agreement between the calculated wave function and the asymptotics formulae is reached. Information about the values of the three-body asymptotic normalization factors is extracted.

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Calculating Masses of Pentaquarks Composed of Baryons and Mesons

Advances in High Energy Physics ◽

10.1155/2016/6480926 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4 ◽

Cited By ~ 7

Author(s):

M. Monemzadeh ◽

N. Tazimi ◽

Sh. Babaghodrat

Keyword(s):

Integral Equation ◽

Configuration Space ◽

Body Problem ◽

Bound State ◽

Pion Exchange ◽

Exchange Potential ◽

The Masses ◽

Exotic Baryon

We consider an exotic baryon (pentaquark) as a bound state of two-body systems composed of a baryon (nucleon) and a meson. We used a baryon-meson picture to reduce a complicated five-body problem to simple two-body problems. The homogeneous Lippmann-Schwinger integral equation is solved in configuration space by using one-pion exchange potential. We calculate the masses of pentaquarksθc(uuddc¯)andθb(uuddb¯).

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ACCURATE ITERATIVE AND PERTURBATIVE SOLUTIONS OF THE YUKAWA POTENTIAL

International Journal of Modern Physics E ◽

10.1142/s0218301306004806 ◽

2006 ◽

Vol 15 (06) ◽

pp. 1253-1262 ◽

Cited By ~ 18

Author(s):

M. KARAKOC ◽

I. BOZTOSUN

Keyword(s):

Numerical Methods ◽

Schrödinger Equation ◽

Schrodinger Equation ◽

State Energy ◽

Yukawa Potential ◽

Bound State ◽

Asymptotic Iteration Method ◽

Bound State Energy ◽

Energy Eigenvalues ◽

Radial Schrödinger Equation

We apply the asymptotic iteration method to solve the radial Schrödinger equation for the Yukawa type potentials. The solution of the radial Schrödinger equation by using different approaches requires tedious and cumbersome calculations; however, we present that it is possible to obtain the bound state energy eigenvalues for any n and ℓ values easily within the framework of this method. We also show the perturbed application of this method for the same potential. Our results are in excellent agreement with the findings of the SUSY perturbation, 1/N expansion and numerical methods.

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Configuration-space faddeev calculations: Numerical methods

Models and Methods in Few-Body Physics - Lecture Notes in Physics ◽

10.1007/3-540-17647-0_25 ◽

2008 ◽

pp. 64-99 ◽

Cited By ~ 12

Author(s):

G. L. Payne

Keyword(s):

Numerical Methods ◽

Configuration Space

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Particle representation for $NN{\bar K}$ system

SciPost Physics Proceedings ◽

10.21468/scipostphysproc.3.044 ◽

2020 ◽

Cited By ~ 1

Author(s):

Branislav Vlahovic ◽

Igor Filikhin ◽

Roman Ya. Kezarashvili

Keyword(s):

Quantum System ◽

Configuration Space ◽

Bound States ◽

Bound State ◽

Particle Model ◽

Faddeev Equations ◽

Quasi Bound State

In the framework of the Faddeev equations in configuration space we perform an analysis of quasi-bound state of the NN{\bar K}NNK‾ system within a particle model. In our approach, the system NN{\bar K}(s_{NN}=0)NNK‾(sNN=0) (NN{\bar K}(s_{NN}=1))NNK‾(sNN=1)) is described as a superposition of ppK^{-}ppK− and pn{\bar K}^0pnK‾0 (nn{\bar K}^{0}nnK‾0 and pn{ K}^-pnK−) states, which is possible due to a particle transition. The relation of the particle model to the theory of a two-state quantum system is addressed and discussed taking into account the possibilities of deep and shallow NN{\bar K}(s_{NN}=0)NNK‾(sNN=0) quasi-bound states.

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CRYO-Electron Microscopy of the Acto-Myosin-ATP Complex

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100179993 ◽

1990 ◽

Vol 48 (1) ◽

pp. 248-249

Author(s):

John Trinickt ◽

Howard White

Keyword(s):

Electron Microscopy ◽

Atp Hydrolysis ◽

Myosin Head ◽

Bound State ◽

Cross Linking ◽

Weakly Bound ◽

Cryo Electron Microscopy ◽

Myosin Subfragment 1 ◽

Attached State ◽

High Fraction

The primary force of muscle contraction is thought to involve a change in the myosin head whilst attached to actin, the energy coming from ATP hydrolysis. This change in attached state could either be a conformational change in the head or an alteration in the binding angle made with actin. A considerable amount is known about one bound state, the so-called strongly attached state, which occurs in the presence of ADP or in the absence of nucleotide. In this state, which probably corresponds to the last attached state of the force-producing cycle, the angle between the long axis myosin head and the actin filament is roughly 45°. Details of other attached states before and during power production have been difficult to obtain because, even at very high protein concentration, the complex is almost completely dissociated by ATP. Electron micrographs of the complex in the presence of ATP have therefore been obtained only after chemically cross-linking myosin subfragment-1 (S1) to actin filaments to prevent dissociation. But it is unclear then whether the variability in attachment angle observed is due merely to the cross-link acting as a hinge.We have recently found low ionic-strength conditions under which, without resorting to cross-linking, a high fraction of S1 is bound to actin during steady state ATP hydrolysis. The structure of this complex is being studied by cryo-electron microscopy of hydrated specimens. Most advantages of frozen specimens over ambient temperature methods such as negative staining have already been documented. These include improved preservation and fixation rates and the ability to observe protein directly rather than a surrounding stain envelope. In the present experiments, hydrated specimens have the additional benefit that it is feasible to use protein concentrations roughly two orders of magnitude higher than in conventional specimens, thereby reducing dissociation of weakly bound complexes.

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