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1.
Takayuki Myo 《Few-Body Systems》2013,54(7-10):849-855
We propose a new theoretical approach to describe nucleus using bare nuclear interaction, in which the tensor and short-range correlations are described with the tensor-optimized shell model (TOSM) and the unitary correlation operator method (UCOM), respectively. We use a bare nucleon–nucleon interaction AV8′ and show the spectroscopic results of the He and Li isotopes with TOSM+UCOM, such as the importance of the pn pair correlated by the tensor force and the corresponding high momentum components.  相似文献   

2.
The tensor interaction plays an important role to determine the nuclear structure. In this study, we propose a tensor-optimized few-body model (TOFM) in the few body framework with bare nucleon-nucleon interaction. In TOFM, the configurations caused by the one-operation of the tensor operator to the S-wave ground state are introduced in the total wave function. It is shown that TOFM reproduces more than 90 % of the total binding energy and the tensor correlation of the few-body results for s-shell nuclei. We further apply TOFM to the p-shell, as 5He. We work out the variational calculation for 5He and discuss the structure difference between two resonance states 3/2? and 1/2?. In particular, we shed light on the roles of the tensor interaction in two states, such as the LS splitting energy.  相似文献   

3.
We give a presentation of the endomorphism algebra ${\rm End}_{\mathcal {U}_{q}(\mathfrak {sl}_{2})}(V^{\otimes r})$ , where V is the three-dimensional irreducible module for quantum ${\mathfrak {sl}_2}$ over the function field ${\mathbb {C}(q^{\frac{1}{2}})}$ . This will be as a quotient of the Birman–Wenzl–Murakami algebra BMW r (q) : =  BMW r (q ?4, q 2 ? q ?2) by an ideal generated by a single idempotent Φ q . Our presentation is in analogy with the case where V is replaced by the two-dimensional irreducible ${\mathcal {U}_q(\mathfrak {sl}_{2})}$ -module, the BMW algebra is replaced by the Hecke algebra H r (q) of type A r-1, Φ q is replaced by the quantum alternator in H 3(q), and the endomorphism algebra is the classical realisation of the Temperley–Lieb algebra on tensor space. In particular, we show that all relations among the endomorphisms defined by the R-matrices on ${V^{\otimes r}}$ are consequences of relations among the three R-matrices acting on ${V^{\otimes 4}}$ . The proof makes extensive use of the theory of cellular algebras. Potential applications include the decomposition of tensor powers when q is a root of unity.  相似文献   

4.
We have reviewed our theoretical calculations of the formation of a deeply bound K ? pp state with I = 1/2, J π  = 0? by the 3He(in-flight K ?, n) reaction at ${p_{K^-} = 1.0}$ rm GeV/c and θ lab = 0° for the forthcoming J-PARC E15 experiment. The expected inclusive and semiexclusive spectra have been calculated within the framework of a distorted-wave impulse approximation using the Green’s function method. The advantage of the use of the 3He target for the 3He(K ?, N) reactions are emphasized.  相似文献   

5.
The Heidelberg shape-effect model for heavy-ion tensor interactions is reformulated and generalized using the Hooton-Johnson formulation. The generalized semiclassical model (the turning-point model) predicts that the components of the tensor analysing power T2q have certain relations with each other for each type of tensor interaction (TR, TP and TL types). The predicted relations between the T2q are very simple and have a direct connection with the properties of the tensor interaction at the turning point. The model predictions are satisfied in quantum-mechanical calculations for 7Li and 23Na elastic scattering from 58Ni in the Fresnel-diffraction energy region. As a consequence of this model, it becomes possible to single out effects from a TP? or TL-type tensor interaction in polarized heavy-ion scattering. The presence of a TP-type tensor interaction is suggested by measured T20/T22 ratios for 7Li+58Ni scattering. In the turning-point model the three types of tensor operator are not independent, and this is found to be true also in a quantum-mechanical calculation. The model also predicts relations between the components of higher-rank tensor analysing power in the presence of a higher-rank tensor interaction. The rank-3 tensor case is discussed in detail.  相似文献   

6.
Tensor correlations in 4He were studied via the (p, dp) reaction at the incident energy of 392 MeV with a focus on spin configurations of correlated pn pairs in 4He at high relative momenta ${(P_{\rm rel}^{\rm cor})}$ . The preliminary results show that the correlated pn pair at ${P_{\rm rel}^{\rm cor} = 310 {\rm MeV/c}}$ predominantly has the channel spin S = 1, which is consistent with the characteristics of tensor correlations.  相似文献   

7.
We describe a 3He magnetometer capable to measure high magnetic fields (B> 0.1 T) with a relative accuracy of better than 10-12. Our approach is based on the measurement of the free induction decay of gaseous, nuclear spin polarized 3He following a resonant radio frequency pulse excitation. The measurement sensitivity can be attributed to the long coherent spin precession time T2 ? being of order minutes which is achieved for spherical sample cells in the regime of “motional narrowing” where the disturbing influence of field inhomogeneities is strongly suppressed. The 3He gas is spin polarized in situ using a new, non-standard variant of the metastability exchange optical pumping. We show that miniaturization helps to increase T2 ? further and that the measurement sensitivity is not significantly affected by temporal field fluctuations of order 10-4.  相似文献   

8.
Tensor representation in teleportation and controlled teleportation   总被引:1,自引:0,他引:1  
We propose the tensor representation of teleportation and controlled teleportation. By using this representation, it is easy to describe the process of teleporting an unknown N-qubit state via a genuine 2N-qubit channel, and to find the necessary and sufficient condition of realizing a successful teleportation (which is determined by the measurement matrix Tα and the quantum channel parameter matrix X). For controlled teleportation, if composing tensor representation with graph, one can easily design any kind of controlled teleportation. As examples, we give a scheme of symmetrically controlled teleportation of two-qubit states and a scheme of representative network controlled of three-qubit states. This method can also be generalized to the controlled teleportation of N-qubit states.  相似文献   

9.
We theoretically demonstrate the inclusive and semiexclusive spectra in the 3He (K ?, π ?) reactions at 600 MeV/c (4°) within a distorted-wave impulse approximation, using a coupled (2N ? Λ) + (2N ? Σ) model with a spreading potential. It is shown that a signal of a ${^3_\Sigma{\rm He}}$ quasibound state is clearly observed near the Σ threshold in the π ? spectrum, whereas a peak of a ${^3_\Sigma{\rm n}}$ quasibound state is relatively reduced in the π + spectrum. The mechanism of Σ production for these spectra is discussed.  相似文献   

10.
Elastic and inelastic scattering of 7Li by 58Ni at Elab = 14.2 and 20.3 MeV is investigated theoretically, special emphasis being laid on polarization phenomena. A parameter-independent study shows second-rank tensor interactions to be the main origin of tensor analyzing powers for both elastic and inelastic scattering. Coupled-channel (CC) calculations using cluster-folding interactions which include the tensor terms are found to be successful in reproducing the data for cross sections and vector and tensor analyzing powers, when projectile excitation effects are sufficiently taken into account. Scattering of 6Li by 58Ni at Elab = 20.0 MeV is also investigated by the CC calculation, where successes similar to the 7Li case are obtained in understanding experimental data.  相似文献   

11.
A technique is proposed for determining the orientation of the orbital anisotropy axis in 3He A. It relies upon the anisotropy of the dielectric tensor which is estimated to be 3×10?7 (1?T/Tc) in 3He A.  相似文献   

12.
The effect of chloride concentration on Mn2+ (S = 5/2, I = 5/2) ions in frozen aqueous solutions is studied by high-field high-frequency electron paramagnetic resonance (HFEPR). The usually six sharp lines characteristic of Mn2+ ions, arising from the m s  = ?1/2 → 1/2 transition, is modified by the addition of Cl? anions and the six resonances become much broader and more complex. This new feature likely arises from the ligation of one Cl? anion to a hydrated Mn2+ ion forming a [Mn(H2O)5Cl]? complex. This complex increases linearly with Cl? concentration with an association constant of K a, apparent = 61 M?1. The structure of the putative chloride complex was studied using density functional theory calculations and the expected zero-field interaction of such a manganese center was calculated using the superposition model. The predicted values were similar to those determined from the simulation of the spectrum of the m s  = ?5/3 → ?3/2 transition of the chloride complex. This effect of Cl? anions occurs at biologically relevant concentration and can be used to probe the Mn2+ ions in cellular and protein environments.  相似文献   

13.
14.
We consider a problem in random matrix theory that is inspired by quantum information theory: determining the largest eigenvalue of a sum of p random product states in \({(\mathbb {C}^d)^{\otimes k}}\), where k and p/d k are fixed while d → ∞. When k = 1, the Mar?enko-Pastur law determines (up to small corrections) not only the largest eigenvalue (\({(1+\sqrt{p/d^k})^2}\)) but the smallest eigenvalue \({(\min(0,1-\sqrt{p/d^k})^2)}\) and the spectral density in between. We use the method of moments to show that for k > 1 the largest eigenvalue is still approximately \({(1+\sqrt{p/d^k})^2}\) and the spectral density approaches that of the Mar?enko-Pastur law, generalizing the random matrix theory result to the random tensor case. Our bound on the largest eigenvalue has implications both for sampling from a particular heavy-tailed distribution and for a recently proposed quantum data-hiding and correlation-locking scheme due to Leung and Winter.Since the matrices we consider have neither independent entries nor unitary invariance, we need to develop new techniques for their analysis. The main contribution of this paper is to give three different methods for analyzing mixtures of random product states: a diagrammatic approach based on Gaussian integrals, a combinatorial method that looks at the cycle decompositions of permutations and a recursive method that uses a variant of the Schwinger-Dyson equations.  相似文献   

15.
Amplitudes for A2 quantum number exchange in K±N scattering are determined at pL = 3, 4 and 6 GeV using new K±N CEX differential cross-section data supplemented by sum rule estimates of polarizations. Amplitudes for ? quantum number exchange are calculated from πN scattering by SU(3) octet symmetry. This is justified by K±N FESR, which furthermore are used to resolve ambiguities in the analysis. Comparison with other reactions involving charge and hyperchange exchange shows reasonable overall consistency between data, SU(3), and the tensor amplitudes. The phase of the A2s-channel helicity flip amplitude is well described by a Regge pole term with trajectory displaced downwards relative to that appropriate for the ? flip amplitude. This is shown to be the main mechanism contributing to the difference between differential cross sections for the K±N CEX processes, connected by line reversal. It is suggested that this mechanism may persist at higher energies. The A2 non-flip amplitude does not have the standard peripheral form.  相似文献   

16.
The233Th(3He,d)233Pa and233Th(α, t)233Pa reactions were studied with 28.5-MeV3He and 30-MeV α-particles, respectively. The reaction results are interpreted in terms of a distorted-wave Born-approximation analysis. Transferred angular momenta are deduced from (α, t) and (3He,d) cross-section ratios,R=dσ(α, t)/dσ(3He,d). Theoretical cross sections, calculated in the framework of the Nilsson model with pairing and Coriolis interactions included, are in reasonable agreement with experiment. Rotational bands built on the following Nilsson proton configurations are identified in233Pa: 1/2?[530↑], 3/2+[651↑], 1/2+[660↑], 5/2+[642↑], 5/2?[5231↓], and 3/2?[521↑].  相似文献   

17.
The formation of a deeply-bound K?? ? pp state by the 3He(in-flight K? n) reaction is investigated theoretically in a distorted-wave impulse approximation using the Green’s function method. The expected inclusive and semi-exclusive spectra at $p_{K^-} = 1.0$ GeV/c and $\theta_n = 0^{\circ}$ are calculated for the forthcoming J-PARC E15 experiment. We discuss these spectra with some K? -“pp” optical potentials, taking into account the energy-dependence of the imaginary part of the potentials by a phase space suppression factor.  相似文献   

18.
We have calculated 7Li(K ?, K +) reaction spectrum at ${p_{K^-} = 1.65}$ GeV/c and ${\theta_{K}^{+} = 0^\circ}$ within the framework of distorted wave impulse approximation (DWIA) using the ${[\Xi^-{-}^6{\rm He}(0^+)]-[\Xi^-{-}^6{\rm He}^*(2^+)]}$ coupled-channel Green’s function approach, and examined whether the peak corresponding to the Ξ ? hypernuclear states can be visible in the reaction spectrum, by employing various Ξ ??6He effective potentials.  相似文献   

19.
The tensor analysing powers T20 and T22 of(d, p) reactions leading to several states of the final nuclei 29Si, 68Zn, 91Zr and 209Pb were measured at 12.3 MeV deuteron beam energy. The measured tensor analysing powers together with the vector analysing power and cross-section data are compared with DWBA calculations with and without the deuteron D-state. The D-state effects and j-dependence of the tensor analysing powers are discussed. The spin transfers involved in populating the 1.08, 1.88 and 3.30 MeV states in 68Zn in the 67Zn(d, p)68Zn reaction are deduced to be predominantly 12?. This implies an assignment for the 3.287 MeV level of 68Zn of Jπ = 2+.  相似文献   

20.
H. Suno  E. Hiyama  M. Kamimura 《Few-Body Systems》2013,54(7-10):1557-1560
The triatomic 4He system and its isotopic species ${^4{\rm He}_2^3{\rm He}}$ are theoretically investigated. By adopting the best empirical helium interaction potentials, we calculate the bound state energy levels as well as the rates for the three-body recombination processes: 4He + 4He + 4He → 4 He2 + 4He and 4He + 4He + 3He → 4He2 + 3He. We consider not only zero total angular momentum J = 0 states, but also J > 0 states. We also extend our study to mixed helium-alkali triatomic systems, that is 4He2 X with X = 7Li, 23Na, 39K, 85 Rb, and 133Cs. The energy levels of all the J ≥ 0 bound states for these species are calculated as well as the rates for three-body recombination processes such as 4He + 4He + 7Li → 4 He2 + 7Li and 4He + 4He + 7Li → 4 He7Li + 4He. In our calculations, the adiabatic hyperspherical representation is employed but we also obtain preliminary results using the Gaussian expansion method.  相似文献   

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