## 1996 Vol. 20, No. S1

Display Method: |

**Abstract:**

A new isotope

^{175}Er was synthesized for the first time by the

^{176}Yb(n,2p)

^{175}Er reaction in irradiation of natural metal ytterbium targets with 14 MeV neutrons. The activities of

^{175}Er were observed by

*γ*(X) ray spectroscopy. Eight new

*γ*rays of 76.5, 120.9, 123.7, 128.5,227.3,234.0,281.4, and 1167.5 keV with half-life of 1.2±0.3 min were found and assigned to the

*β*decay of

^{175}Er. A partial decay scheme of

^{175}Er was proposed.

**Abstract:**

Particle-particle correlation functions have been measured for

^{40}Ar+

^{197}Au collisions at

*E/A*=25 MeV. Emission time of light particles has been extracted from correlation functions using the three-body trajectory model. The average emission time varies with the energy of particles. It decreases from about 300 fm/

*c*for low energy particles to about 100 fm/

*c*for energetic particles.

**Abstract:**

The yields of known hafnium isotopes produced in 6.3-24.6 MeV/nucleon

^{40}Ar+

^{nat}W reactions were determined by

*γ*-ray spectroscopy following chemical separation. The excitation function, the

*FW*value, and isotope distributions were obtained. It was deduced that using HIRFL energy heavy ions to synthesize new neutron-rich nuclides in the

*A*> 170 region is possible. Using thick target or multi-thin target can obviously increase the yield of a new neutron-rich nuclide. Increasing projectile energy is not always helpful to synthesize a new neutron-rich nuclide.

**Abstract:**

By using experimental data obtained from the measurement of

*β*-delayed proton decay of

^{65}Se produced in the

^{40}Ga(

^{28}Si,3n) reaction, the absolute detection efficiency of particle telescope for rotating radioactive source was fitted and calculated. The half-life of

^{65}Se was thus accurately determined to be 9.6

_{-4.1}

^{+5.3}ms and its

*β*-delayed proton energy of

^{65}Se was 3.70±0.08MeV. The partial decay scheme of

^{65}Se

*β*-delayed proton decay was revised.

**Abstract:**

A two-dimensional position sensitive multi-stage detection system with a wide dynamic range for a heavy ion reaction is described in this paper. It consists of four parts:a longitudinal electric field gas filled Ionization Chamber (IC), a Position Sensitive Silicon Detector (PSSD) (45 mm×45 mm, 400

*μ*m), a large area PIN Silicon Photodiode (SPD) (48 mm×48 mm, 300

*μ*m),and a 16 element CsI(Tl) scintillation detector array. The energy resolutions for IC and PSSD tested with a source

^{241}Am(5.486 MeV) are 3% and 2.6%, respectively. The energy dynamic range for

*α*particle detection is about 2-130 MeV, and the fragments with

*Z*Values from

*Z*=2 to

*Z*=21 are identified in the reaction of 25 MeV/u

^{40}Ar+

^{115}In. The

*Z*resolving power is

*Z*/△

*Z*≈ 44.5 (FWHM) for

*Z*=18. The position resolution of PSSD is 0.86±0.03 mm (FWHM).

**Abstract:**

A new neutron-deficient isotope

^{235}Am was synthesized in the reaction of

^{238}Pu(p,4n)

^{235}Am by using 35 MeV proton bombarding

^{238}Pu target. The products were transported by the He-jet system. The Am was separated from the reaction products using the radiochemistry method. The

*γ*-ray of

^{235}Pu and X-ray of Np following the EC decay of

^{235}Am were observed. Based on the growth-decay curve of X-ray of Np and the X-

*γ*coincidence measurements, the synthesis of

^{235}Am was confirmed for the first time. The measured half-life of

^{235}Am is 15 ±5 min.

**Abstract:**

We construct explicitly the two-dimensional cyclic representation of quantum algebra

*U*

_{q}(

*sl*(2)) with

*q*=

*i*and

*z*central extension. The representation is irreducible and we write down explicitly the Clebsch-Gordan coefficients and the intertwiner of tensor representations in different orders. This intertwiner turns out to be an 8-vertex

*R*-matrix that satisfies the free-Fermion condition and therefore gives an integrable model.

**Abstract:**

A two-parameter

*qp*-deformed two-dimensional interacting boson model (IBM) with the quantum symmetry

*U*

_{qp}(

*U*

_{3})⊃

*U*

_{qp}(

*U*

_{2})⊃

*U*

_{qp}(

*SO*

_{2}) is constructed. It is found that the energy spectra and the transition matrix elements depend very sensitively on the second parameter of deformation.

**Abstract:**

The plaquette internal energy

*E*

_{p}of

*U*(1) lattice gauge theory (LGT) in three dimensions is calculated using the variational cumulant expansion (VCE) with the independent plaquette effective action. The

*E*

_{p}-

*β*curve is continuous, which shows that the

*U*(l) theory is confined. Our result is consistent with Monte Carlo (MC) data.

**Abstract:**

Using the Feynman path integral method, we calculate the Casimir effect of QCD with massive fermion loop contribution between two parallel ideal conducting wires at zero temperature.

**Abstract:**

On the basis of the generalized invariant theory, the invariant-related unitary transformation method is developed and used to study the evolution of the third-quantized wave functions of the universe. The expressions for the phases and the wave functions are obtained. Then, by means of the construction of the coherent state, the solutions of the Wheeler-DeW itt equation and the quantum fluctuations caused by the third quantization are found.

**Abstract:**

The self-affine cascading model of 2-dimensional phase space is discussed in some detail. The analytical expression for the scaled probability inoments,

*C*

_{N}

^{2}and

*C*

_{N}

^{3}are deduced for the self-similar analysis of a 2-dimensional self-affine fractal object with Hurst exponent

*H*=0.5. The Levy stability indices of the model are calculated analytically. It is shown that the results of Levy indices from the Monte Carlo simulation are consistent with those from the analytical calculation. The recent experimental data from NA22 collaboration are explained qualitatively.

**Abstract:**

In this paper, the basic features exhibited by the

^{20}Ne+

^{12}C system are analyzed and the excitation functions and the angular distributions of the

^{20}Ne+

^{12}C elastic scattering are well reproduced on the basis of the nuclear molecular orbital theory. The results show that the double-alpha transfer effect for a deep optical potential is responsible for the basic features in the excitation functions of the

^{20}Ne+

^{12}C elastic scattering.

**Abstract:**

Properties of the low-lying positive-parity states in

^{157, 159}Tm have been investigated by using the triaxial rotor plus particle model with the variable moment of inertia (VMI) of the core. The good agreement between theory and experiment shows that

^{157}Tm and

^{159}Tm may be triaxiality. Furthermore, it is suggested that an excitation rotational band in

^{157}Tm probably already exists in the experimental data.

**Abstract:**

The ground state properties of the doubly-magic nucleus

^{100}Sn were calculated with the Skyrme-Hatree-Fock method. There may be a proton skin in the

^{100}Sn nucleus due to the Coulomb repulsion.

**Abstract:**

The matrix elements of the M-3Y force are adopted as equivalent

*G*-matrix elements and the folded diagram method is used to calculate the spectra of

^{210}Pb,

^{206}Pb,

^{206}Hg, and

^{210}Po. Results show that the matrix elements of the M-3Y force as equivalent

*G*-matrix elements are suitable for the microscopic calculations of the nuclear structure in the heavy nucleus region.

**ISSN** 1674-1137 **CN** 11-5641/O4

Original research articles, Ietters and reviews Covering theory and experiments in the fieids of

- Particle physics
- Nuclear physics
- Particle and nuclear astrophysics
- Cosmology

Author benefits

- A SCOAP3 participating journal - free Open Access publication for qualifying articles
- Average 24 days to first decision
- Fast-track publication for selected articles
- Subscriptions at over 3000 institutions worldwide
- Free English editing on all accepted articles

News

- The 2023 Chinese New Year-Office closure
- 2022 National holiday- office closure
- The 2022 summer holiday-Office closure
- Impact factor of Chinese Physics C is 2.944 in 2021
- The 2022 Labor Day Holiday-Office closure

Meet Editor