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1.
《Physics letters. [Part B]》1986,174(2):133-136
Muonic X-ray spectra of μ3He and μ4He from dμd, pμd, and dμt fusion are analyzed for various target densities. Theoretical values of the intensity ratio μ3He(3→1)/μ3He(2→1) for dμd and pμd fusion at liquid hydrogen density are, respectively, 0.132 and 0.0553. These are in good agreement with the experimental results.  相似文献   

2.
Data from the recent PSI high statistics experiment on d μ d fusion are used to measure the stripping process in d μ d→ n+μ,3He and test current calculations of the stripping process. The PSI results in μ3He capture are also used to remove a troubling background from this measurement. Combination of these results with the old dμ t sticking analysis slightly raise and improve that result to ωs= (0.58± 0.04)% and indicate that theory and experiment can meet if theoretical stripping is increased only at the beginning of the track. This conclusion is in accord with the new stripping calculations where excited state stripping is increased significantly. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

3.
The pionic decay of a possible dibaryon, d’ → πNN, is studied in the model assuming the production of 3 P 0 quark-antiquark pairs and in other models of effective quark-pion coupling. The vertex constants and the form factors for pion-baryon and pion-dibaryon couplings are calculated. The effect of the internal pion structure on decay widths is investigated. It is shown that the quark structure of the nucleon-nucleon wave function in the overlap region plays an important role in dibaryon decays, and known models of nucleon-nucleon interaction are analyzed with allowance for this circumstance. The decay width of a dibaryon is estimated as a function of its effective mass in nuclear matter.  相似文献   

4.
We provide a new class of entanglement witnesses for dd systems (two qudits). Our construction generalizes the one proposed recently by Jafarizadeh et al. for d = 3 and d = 4 on the basis of semidefinite linear programming. Moreover, we provide a new class of PPT entangled states detected by our witnesses which generalizes well known family of states constructed by Horodecki et al. for d = 3.  相似文献   

5.
A collective adiabatic approach is used to explore the total and differential cross sections for the reactions d + dp + 3H and d + dn + 3He at incident-deuteron energies of up to 6 MeV. All substantially contributing partial waves of order not higher than that of G waves are taken into account. The experimental value of the difference of the cross sections for the above mirror reactions is reproduced theoretically under the assumption that nuclear forces obey the condition of isotopic invariance. The positions and amplitudes of the maxima in the calculated total cross sections virtually coincide with those of the corresponding experimental values. It is shown that, around the maxima of the cross sections under study, dominant contributions to them come from the P wave. The sensitivity of observables to the parameters of nucleon-nucleon interaction is analyzed.  相似文献   

6.
7.
《Nuclear Physics A》1997,625(3):598-620
At the Munich Tandem Accelerator the reactions 125Te(d, p)126Te, 126Te(d, d′)126Te and 127I(d, 3He)126Te were measured with deuteron energies between 24 and 28 MeV up to excitation energies of about 3.2 MeV. Using γ-lines from previous (n,γ), (n,n′γ) and (γ,γ′) experiments, a level scheme of 126Te up to above 3 MeV was established. The results are compared with quasiparticle-phonon model calculations.  相似文献   

8.
9.
We first construct a new maximally entangled basis in bipartite systems \(\mathbb {C}^{d} \otimes \mathbb {C}^{kd}\ (k\in Z^{+})\) which is diffrent from the one in Tao et al. (Quantum Inf. Process. 14, 2291 (2015)), then we generalize such maximally entangled basis into arbitrary bipartite systems \(\mathbb {C}^{d} \otimes \mathbb {C}^{d^{\prime }}\). We also study the mutual unbiased property of the two types of maximally entangled bases in bipartite systems \(\mathbb {C}^{d} \otimes \mathbb {C}^{kd}\). In particular, explicit examples in \(\mathbb {C}^{2} \otimes \mathbb {C}^{4}\), \(\mathbb {C}^{2} \otimes \mathbb {C}^{8}\) and \(\mathbb {C}^{3} \otimes \mathbb {C}^{3}\) are presented.  相似文献   

10.
After the feasibility of vacuum isolated d production was demonstrated at TRIUMF in 1989, development was begun on a target system that would take advantage of the process to aid in the understanding of the muon catalyzed fusion cycle. Minimal neutron backgrounds, the ability to use silicon detectors, and compatibility with tritium were considered important for a very versatile target system. The advantages which the target gives in isolating CF process will be outlined.  相似文献   

11.
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13.
A vibrating sample magnetometer (VSM) has been used to study the field-dependent magnetization, M(H), of the d5?d7 metal acetates [M(OAc)2.nH2O], metal β?diketonate complexes [M(tba)2(H2O)2] and the macromolecular polymers [M(tba)2(4,4-bipy)]n (where, M = Mn(II), Fe(II), and Co(II), OAc = O2CCH3, tba = deprotonated 3-benzoyl-1.1.1-trifluoroacetone, and 4,4-bipy = 4,4′-bipyridine). The magnetic field strength (H) was applied in the range of 0?104 Oe at ambient temperature (ca. 23°C). The experimental results showed that the d5?d7 metal acetate, complexes and polymers exhibit low paramagnetic properties excepting [Fe(tba)2(4,4-bipy)]n polymer, which had negative magnetization M(emu/g) showing diamagnetic properties in the range 0?104 Oe. The magnetization was almost equal to zero without an applied magnetic field (H(Oe)) for each d5?d7 metal acetate, complex, and polymer. The linear M(H) curve had a magnetic saturation for iron and manganese acetate species at the magnetic field strengths of 3.1 × 103 and 4.7 × 103 Oe, respectively. The external magnetic field reached 9.0 × 103 Oe without any saturation magnetization for the cobalt compounds. The coordination effect of 3-benzoyl-1.1.1-trifluoroacetone (H-tba) and 4,4′-bipyridine (4,4′-bipy) ligands on the field-dependent magnetization M(H) and paramagnetic behavior of d5?d7 metal atoms is discussed. The field-dependent magnetization M(H) curves of metal β?diketonate complexes and the polymers including d5?d7 metal acetates showed a weak field octahedral geometry.  相似文献   

14.
Model potential calculations have been performed to investigate the influence of valence-core electron exchange on oscillator strengths in the Cs isoelectronic sequence. It is demonstrated that inclusion of valence-core electron exchange in the model potential calculations of oscillator strengths for transitions involving orbitals which undergo the collapse phenomenon (usually d or f orbitals) is important and may modify the character of the transition (emission or absorption) due to the change in the relative positions of the states involved. In the collapse region, oscillator strengths for these transitions may also depend strongly on the form of the exchange approximation used. The reason for this influence is that valence-core electron exchange greatly facilitates the collapse phenomenon, thus affecting the positions of states and radial transition integrals. For transitions which do not involve orbitals undergoing collapse or occur in members of the isoelectronic sequence distant from the collapse region, the exchange effects, although still important are much weaker and good results may be obtained not only with a model potential employing empirically adjusted exchange but also for a simple, free from adjustable parameters, semiclassical exchange approximation.  相似文献   

15.
In the past few years we have derived asymptotic expansions for λ d of the dimer problem and λ d (p) of the monomer-dimer problem. The many expansions so far computed are collected herein. We shine a light on results in two dimensions inspired by the work of M.E. Fisher. Much of the work reported here was joint with Shmuel Friedland.  相似文献   

16.
In this paper, we show that the Lax connections can yield new classical solutions with a spectral parameter of the hybrid formulism for the Type IIB superstring in an AdS2 × S2 background with Ramond-Ramond flux. This series of classical solutions have the same infinite set of classically conserved charges.  相似文献   

17.
The measurement of parity-violating (PV) observables in few-nucleon system can shed light on our current understanding of the weak interaction between nucleons.Theoretical models describe the nucleonnucleon weak interaction at low energies use a series of undetermined parameters.Two parity violating measurements have been considered: the capture of polarized slow neutrons on hydrogen (n + p → d + γ) at Los Alamos National Laboratory for first phase and Oka Ridge National Laboratory for second phase and the helicity dependence of the deuteron photodisintegration cross section using circularly polarized photons (γ + d → n + p) at Shanghai Institute of Applied Physics.The goal of both experiments is to constraint the weak meson-nucleon couplings to a precision of 1 ×10-8 .The introduction of both experiments is presented.  相似文献   

18.
In this paper we study the spinor constructions of gauge fluxes and Ramond-Ramond fields on noncommutative tori T^d up to d=6. In which the spinor and conjugate spinor are distinguished and dual bases are also introduced.So that we can express the Chern-Simons Lagrangian in toroidal compactification as a product of spinors.  相似文献   

19.
We perform a study of the final-state interactions of the K + and the d systems in the reactions ppdK + and ppdπ+η. Since the two-meson system couples strongly to the a 0(980) resonance, these reactions are expected to be an additional source of information about the controversial scalar sector. We also show that these reactions present peculiar features which can shed additional light on the much debated meson-baryon scalar sector with strangeness -1. We deduce the general structure of the amplitudes close to the dK + threshold, allowing for primary K + as well as π+η production with the two mesons in relative S- or P-wave. The interactions of the mesons are accounted for by using chiral unitary techniques, which generate dynamically the a 0(980) resonance, and the d interaction is also taken into account. General formulae are derived that allow to incorporate the final-state interactions in these systems for any model of the production mechanism. We illustrate this approach by considering two specific production mechanisms based on three flavor meson-baryon chiral perturbation theory. It is demonstrated that in this scenario the d interactions are very important and can change the cross-section by as much as one order of magnitude. The amount of π+ηversus K + production is shown to depend critically on the primary mixture of the two mechanisms, with large interference effects due to final-state interactions. These effects are also shown to occur in the event distributions of invariant masses which are drastically modified by the final-state interactions of the two-meson or the d system. Received: 28 September 2001 / Accepted: 26 November 2001  相似文献   

20.
The unambiguous assignment of the aromatic protons of the duplex d(CA)3·d(TG)3 was carried out with the aid of HMQC and HMBC inverse detected13C NMR experiments atT=278 K. The NOE connections of these protons with the imino protons of the complementary bases — established by 2D NOESY experiments — indicated that the duplex is characterized by a canonical Watson-Crick basepairing pattern. Monodimensional1H NMR experiments, also carried out atT=278K, in the presence of varying amounts of NaCl and with water suppression by presaturation and by spin echo techniques, showed that the imino protons of the TA and CG pairs of the duplex exchange with water through a process of local base pair opening and with different exchange rates.  相似文献   

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