Authors:Ma Zhong-Qi; Yan Zong-Chao First page: 063104 Abstract: The rotational invariants constructed by the products of three spherical harmonic polynomials are
expressed generally as homogeneous polynomials with respect to the three coordinate vectors in the
compact form, where the coefficients are calculated explicitly in this paper. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:M. Ghazvini; N. Salehi, H. Hassanabadi A. A. Rajabi First page: 063106 Abstract: In this paper, the Schr?dinger equation for a 6-body system is studied. We solve this equation for
the lithium nucleus by using a supersymmetry method with several specific potentials. These
potentials are the Yukawa potential, the generalized Yukawa potential and the Hellmann potential.
The results of our model for all calculations show that the ground state binding energy of the
lithium nucleus with these potentials is very close to that obtained experimentally. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Liu Lang First page: 064101 Abstract: The low-lying spectra of 7 Li and 9 Li are investigated within an ab initio Monte Carlo Shell Model
(MCSM) employing a realistic potential obtained via the Unitary Correlation Operator Method (UCOM).
The MCSM calculations in a 4-major-shells model space for the binding energy and mass quadrupole
moment of 7,9 Li show good convergence when the MCSM dimension reaches 20. The excitation energy of
the J ? = 1/2 ? state for 7 Li and the magnetic moments for 7,9 Li ground states in the MCSM with a
treatment of spurious center-of-mass motion are close to the experimental data. Correct level
ordering of J ? = 3/2 ? and 1/2 ? states for 7,9 Li can be reproduced due to the inclusion of
three-body correlations in the MCSM+UCOM. However, the excitation energy of J ? = 1/2 ? state for 9
Li is not reproduced in the MCSM mainly d... Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Mahesh K. Sharma; R. N. Panda, Manoj K. Sharma S. K. Patra First page: 064102 Abstract: We study the structural properties of some light mass nuclei using two different formalisms (i) a
recently developed simple effective interaction in the frame work of microscopic non-relativistic
Hartree-Fock method and (ii) the well-known relativistic mean field approach with NL3 parameter set.
The bulk properties like binding energy, root mean square radii and quadrupole deformation parameter
are estimated and compared with the available experimental data. The predicted results of both the
formalisms are well comparable with the experimental observations. The analysis of density profiles
of these light mass nuclei suggest that 22 O, 23 F, 34 Si and 46 Ar have bubble like structure. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Chen Hua-Xing; Shotaro Imai, Hiroshi Toki Geng Li-Sheng First page: 064103 Abstract: We study properties of hadrons in the O (4) linear ? model, where we take into account fluctuations
of mesons around their mean field values using the Gaussian functional (GF) method. In the GF method
we calculate dressed ? and ? masses, where we include the effect of fluctuations of mesons to find a
better ground state wave function than the mean field approximation. Then we solve the
Bethe-Salpeter equations and calculate physical ? and ? masses. We recover the Nambu-Goldstone
theorem for the physical pion mass to be zero in the chiral limit. The ? meson is a strongly
correlated meson-meson state, and seems to have a two meson composite structure. We calculate ? and
? masses as functions of temperature for both the chiral limit and explicit chiral symmetry breaking
case. We get similar behaviors for the physical ? and ? masses as the case of the mean field
approximation, but the coupling constants are much larger than the values of the case of the mean
field approximation... Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Huang Wei-Ping; Tang Ze-Bo, Li Cheng, Jiang Kun, Zhao Xiao-Kun Wang Peng-Fei First page: 066003 Abstract: The water Cherenkov detector array (WCDA) for the Large High Altitude Air Shower Observatory
(LHAASO) will employ more than 3600 hemisphere 8-inch photomultiplier tubes (PMTs). Good time
performance of the PMT, especially the transit time spread (TTS), is required for the WCDA. In order
to meet the demand of the WCDA experiment, an accurate measurement of PMT TTS based on the
photoelectron spectrum is studied. The method is appropriate for multi-photoelectrons and makes it
possible to measure the TTS of different photoelectrons simultaneously. The TTS of different
photoelectrons for a Hamamatsu R5912 PMT is tested with a specially designed divider circuit. The
relationship between TTS and number of photoelectrons is also presented in this paper. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Li Rong-Hua; Li Zhan-Kui, Yang Lei, Li Dong-Mei, Li Hai-Xia, Wang Zhu-Sheng, Chen Cui-Hong, Tan Ji-Lian, Liu Feng-Qiong, Rong Xin-Juan, Wang Xiu-Hua, Li Chun-Yan, Zu Kai-Ling Lu Zi-Wei First page: 066004 Abstract: Nonionizing energy loss (NIEL) has been applied to a number of studies concerning displacement
damage effects in materials and devices. However, most studies consider only the contribution of
displacement damage effects, neglecting the contribution from phonons. In this paper, a NIEL model,
which considers the contribution of phonons, has been established using the Monte Carlo code SRIM.
The maximum endurable fluence for silicon detectors has been estimated using the equivalent
irradiation fluence compared with experimental data for the incident particles. NIEL is proportional
to the equivalent irradiation fluence that the detector has received. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Ahmed M. M. Elsied; Nasr A. M. Hafz, Li Song, Mohammad Mirzaie, Thomas Sokollik Zhang Jie First page: 067003 Abstract: At Shanghai Jiao Tong University (SJTU) we have established a research laboratory for advanced
acceleration research based on high-power lasers and plasma technologies. In a primary experiment
based on the laser wakefield acceleration (LWFA) scheme, multi-hundred MeV electron beams of
reasonable quality are generated using 20?40 TW, 30 femtosecond laser pulses interacting
independently with helium, neon, nitrogen and argon gas jet targets. The laser-plasma interaction
conditions are optimized for stabilizing the electron beam generation from each type of gas. The
electron beam pointing angle stability and divergence angle as well as the energy spectra from each
gas jet are measured and compared. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Zhou Jian-Bin; Liu Yi, Hong Xu, Zhou Jin, Ma Ying-Jie, Wang Min, Hu Yun-Chuan, Chen Bao Yue Ai-Zhong First page: 068201 Abstract: Energy resolution is affected by the intrinsic energy resolution of the detector, ballistic deficit,
pile-up pulses and noise. Pile-up pulses become the dominant factor that degrades energy resolution
after the system is established, so pile-up rejection is often applied to obtain good energy
resolution by discarding pulses that are expected to be contaminated by pile-up. However, pile-up
rejection can reduce count rates and thus lower the measurement precision. In order to improve count
rates and maintain energy resolution, a new method of pile-up pulse identification based on
trapezoidal pulse shaping is presented. Combined with pulse width discrimination, this method is
implemented by recording pulses that are not seriously piled up. Some experimental tests with a
Cu-Pb alloy sample are carried out to verify the performance of this method in X-ray spectrometry.
The results show that the method can significantly improve count rates without degrading energy
resolution. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)

Authors:Zhang Jin-Zhao; Tuo Xian-Guo First page: 068202 Abstract: A geometric matrix model of nuclear waste drums is proposed for transmission image reconstruction
from tomographic gamma scans (TGS). The model assumes that rays are conical, with intensity
uniformly distributed within the cone. The attenuation coefficients are centered on the voxel (cube)
of the geometric center. The proposed model is verified using the EM algorithm and compared to
previously reported models. The calculated results show that the model can obtain good
reconstruction results even when the sample models are highly heterogeneous. Citation: Chinese Physics C PubDate: 2015-06-11T00:00:00Z Issue No:Vol. 39, No. 6 (2015)