In-beam study of excited states in the nucleus150Nd

Energy levels and decay scheme of the nucleus¹⁵⁰Nd produced by using 10 MeV deuterons have been investigated with efficientγ-γ coincidence equipment during an in-beam¹⁵⁰Nd bombardment. In addition to the ground band, aK ^π=0^? octupole band is strongly populated allowing the identification of its three lowest members. The assignments of the levels are based on coincidence data and on systematic comparison with the (d, d′) cross sections known from three other doubly-evenN=90 nuclei. The decay properties of the 1/2⁺ levels in¹⁴⁹Nd populated in this study through the (d, tγ) reaction are also discussed.     

上海光源150MeV电子直线加速器的设计与调试

上海光源150MeV直线加速器由热阴极电子枪, 次谐波聚束器和聚束器, 四根S波段等梯度行波加速管及必要的磁铁等组成. 外围还有由从微波到直流的电源和功率源, 性能监测和联锁控制的硬件和软件等. 概述了150MeV直线加速器的设计, 安装, 调试和达到的结果.     

上海光源150MeV电子直线加速器的设计与调试

上海光源150MeV直线加速器由热阴极电子枪,次谐波聚束器和聚束器,四根S波段等梯度行波加速管及必要的磁铁等组成.外围还有由从微波到直流的电源和功率源,性能监测和联锁控制的硬件和软件等.概述了150MeV直线加速器的设计,安装,调试和达到的结果.     

Generation of field cluster states through collective operation of cavity QED disentanglement eraser

We investigate effects of a collective disentanglement eraser performed over states of two pairs of pre-entangled cavities tagged independently with two identical three-level atoms. It is shown that the collective disentanglement operation ensures not only the recovery of initial coherence but also its extension from the initial two to four qubits, generating four-qubit field cluster states. We also propose a cavity QED scheme to generate an arbitrary field graph state by means of a collective operation of disentanglement erasers.     

Nd3+ near UV and visible fluorescence in YAP:Nd

The present paper summarizes detailed investigations of Nd³⁺ fluorescence spectra in YAP:Nd laser crystal in the broad spectral range of 370–1100 nm at liquid nitrogen temperature. Especially, Nd³⁺ near UV and visible fluorescence spectra were studied for the first time in this crystal. The Nd³⁺ near UV and visible fluorescence spectra of this crystal consist of many narrow lines (up to 50). The Nd³⁺ near UV and visible fluorescence lines arise mainly from⁴D_3/2 and²P_3/2 Nd³⁺ terms (transitions from⁴D_3/2,²P_3/2 to lower lying Nd³⁺ levels are responsible for their appearance). At room temperature the fluorescence spectra consist of broad bands with narrow lines (mainly⁴D_3/2⁴F_3/2,⁴F_5/2 and²H_9/2 transitions).     

Bound ro-vibronic states of triplet H3(+)

On the basis of a new, highly accurate potential energy hypersurface for the lowest triplet state of H+3, (3)Sigma(+)(u), the bound ro-vibronic states are calculated for J相似文献   

On relaxation of entangled states in a collective thermostat

A kinetic equation describing collective relaxation process in the dispersion limit is derived for an ensemble of two-level atoms placed in a cavity and interacting with one cavity mode. Multiatom entangled states belonging to the set of Dicke states and insensitive to collective decay are found. A scheme for recording, storing, and reading these states with participation of spatially multimode light is reported.     

Low temperature cluster glass behavior in Nd5Ge3

Various experimental evidence obtained from dc and ac magnetization measurements indicates that Nd(5)Ge(3) undergoes a spin glass transition from a high temperature antiferromagnetic state. Below the Néel temperature of 49 K, it shows distinct properties that characterize a cluster glass state, thereby indicating that it is an example of a reentrant spin glass system. Dynamical behavior of the magnetic susceptibility and the magnetic relaxation clearly give evidence of frustration in the material. Geometric frustration arising from the triangular arrangement of Nd atoms seems to be the main reason behind the spin glass state. A field-induced structural distortion accompanying the Néel transition may also be responsible for the frustration and the spin glass state.     

Microscopic description of collective states near the yrast line of nuclei with stable octupole deformation

Collective states near the yrast line in nuclei with stable octupole deformation are discussed in the framework of the random phase approximation (RPA) based on the cranking model. These vibrational states are characterized by the quantum number of generalized signature (eigenvalue of the operator S_x = PR_x^?1(π)). In the zero-octupole deformation limit the RPA equations of motion are reduced to the well-known ones characterized by both values of parity and signature, respectively. The connection of the translational and rotational symmetry of the model hamiltonian with the spurious solutions of the RPA equation of motion is discussed. Expressions for the reduced probabilities B(E1), B(E2) and B(E3) are obtained. These expressions confirm the conclusions of phenomenological models for the strong E1 and E3 intraband transitions in nuclei with stable octupole deformation.     

Evidence for cluster emission in fusion reactions between 48Ti and 45Sc at 16 MeV/u

The reaction mechanism in collisions between ⁴⁸Ti and ⁴⁵Sc at 16 MeV/u leading to evaporation-residue-like fusion products (ER) was investigated by measuring and analyzing the ER velocity distributions as a function of ER mass. As expected for this nearly symmetric system the average ER velocities were found to be very close to the center-of-mass velocity. From the widths of the velocity distributions, quantitatively expressed by the variances S_x² and S_z² perpendicular and parallel to the beam direction, information on the recoil momenta of the emitted particles can be obtained. The quantitative analysis yields strong evidence for an incomplete-fusion process during which several correlated or clustered particles are emitted. An estimate of the cluster mass leads to mass numbers ranging from 10 to 20 depending on the ER mass. This interpretation is consistent with the measured ER cross section exceeding the value derived from the stability limit of the compound nucleus by a factor of two.     

Phenomenological Study of 3He Photodisintegration up to 150MeV

A parametrization of ^3He（7,p）2H cross section data at laboratory photon energies between 9 and 150MeV iscarried out with a simple phenomenological function. The differential cross section data are normalized to the total cross-section values which are consistent with the measurement from monochromatic photon beams. The obtained results give a good representation of the experimental points.     

Evidence for a spin-5 boson resonance at 2300 MeV

Evidence is given for the existence of a spin-5 boson resonance from the analysis of the reaction π^?p→K⁺K^?n at 62 GeV incident momentum. A simplified amplitude analysis with a Breit-Wigner ansatz leads to a mass 2307 ± 6 MeV and a width of 245 ± 20 MeV. The quantum numbers of the resonance are J^P = 5^?, C = ?1, and very probably I^G = 1⁺.     

Search for the ρρ enhancement near 1700 MeV/c in the reaction at 8.3 GeV/c

Results are presented from a search for a ρ⁰ρ⁰ enhancement in antiproton annihilations. A ρ⁰ρ⁰ resonance was recently observed in radiative ψ decays, and its existence has been supported by the results of an antiproton experiment at 5.7 GeV/c. No indication of this ρ⁰ρ⁰ enhancement is seen is our data, in direct contradiction with the earlier, lower statistics experiment.     

Generation of cluster states for cavity fields

This paper proposes an alternative scheme for generating cluster-type of entangled coherent states. This scheme is based on resonant interaction of a two-mode cavity with a two-level atom driven by strong classical fields. Thus the required interaction time is greatly shortened, which is very important in view of decoherence.