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921.
A. Covello L. Coraggio A. Gargano N. Itaco 《The European physical journal. Special topics》2007,150(1):93-96
We report on a study of exotic nuclei around doubly magic 132Sn in terms of the shell model employing a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential.
The short-range repulsion of the bare potential is renormalized by constructing a smooth low-momentum potential, Vlow-k, that is used directly as input for the calculation of the effective interaction. In this paper we focus attention on the
nuclei
134Sn and 135Sb which, with an N/Z ratio of 1.68 and 1.65, respectively, are at present the most exotic nuclei beyond 132Sn for which information exists on excited states.
Comparison shows that the calculated results for both nuclei are in very good agreement with the experimental data. We present
our predictions of the hitherto unknown spectrum of
136Sn. 相似文献
922.
923.
C. H. Hyun S. Ando B. Desplanques 《The European Physical Journal A - Hadrons and Nuclei》2007,32(4):513-515
We calculate the parity-violating nucleon-nucleon potential in heavy-baryon chiral perturbation theory up to next-to-next-to-leading
order. The one-pion exchange enters in leading order and the next-to-next-to-leading order consists of two-pion-exchange and
the two-nucleon contact terms. In order to investigate the effect of the higher-order contributions, we calculate the parity-violating
asymmetry in n
p → dγ at threshold. The one-pion-exchange contribution dominates the physical observable, while the two-pion-exchange contribution
is about or less than 10% of the one-pion-exchange one. 相似文献
924.
925.
Shubi F. Kaijage Yoshinori Namihira Nguyen H. Hai Feroza Begum S. M. Abdur Razzak Tatsuya Kinjo Hiroki Higa Nianyu Zou 《Optical Review》2008,15(1):31-37
In this paper, we present a dispersion controlling technique with a multiple defect-core hexagonal photonic crystal fiber
(MD-HPCF). By omitting air holes in the core region of the conventional HPCF and adjusting the size of air holes around the
newly formed core, we can successfully design low flattened dispersion PCF with low confinement loss, as well as high birefringence.
The low flattened dispersion feature, as well as the low confinement losses and high birefringence are the main advantages
of the proposed PCF structure, making it suitable as chromatic dispersion controller, dispersion compensator, and/or polarization
maintaining fiber. 相似文献
926.
利用分子束外延生长获得的两个InAs量子点样品制备了n型的量子点红外探测器.对于其中一个器件,在InAs量子点有源区的底部和顶部分别插入生长了AlGaAs势垒层.利用透射电阻显微技术研究了两个样品的结构特性;利用光致发光光谱和光电流谱研究了两个器件的光电性质.实验结果表明,AlGaAs层的插入对器件的探测性质有显著的影响.利用有三维效质量近似模型的计算结果,指认了带内光电流谱中峰结构的起源. 相似文献
927.
利用基于有效介质理论的介孔硅传热机理,提出一个用于分析氧化介孔硅热导率的理论模型,对影响氧化介孔硅有效热导率的因素进行了理论分析,得出用于计算氧化介孔硅有效热导率的计算公式. 采用双槽电化学腐蚀法制备介孔硅,利用微拉曼光谱技术研究了氧化介孔硅热导率随所制备介孔硅孔隙率的变化规律,比较了经不同温度处理的氧化介孔硅的导热性能差异. 孔隙率为60%,73.4%和78.8%的所制备介孔硅经300℃氧化处理后,其热导率值为8.625W/(m·K),3.846W/(m·K)和1.817W/(m·K);孔隙率为73.4 相似文献
928.
We derived the theoretical results of soliton interactions in optical fiber with super-Gaussian slidingfrequency filters. The results demonstrate that the interactions between optical fiber solitons can be effectively suppressed by super-Gaussian sliding-frequency filters. And the results also show that the super-Gaussian filter with sliding is more effective in suppressing soliton interactions than that without sliding. 相似文献
929.
Received July 2, 2001 / Published online February 4, 2002 相似文献
930.
Norman Margolus 《International Journal of Theoretical Physics》2003,42(2):309-327
Although not always identified as such, information has been a fundamental quantity in Physics since the advent of Statistical Mechanics, which recognized counting states as the fundamental operation needed to analyze thermodynamic systems. Quantum Mechanics (QM) was invented to fix the infinities that arose classically in trying to count the states of Black Body radiation. In QM, both amount and rate of change of information in a finite physical system are finite. As Quantum Statistical Mechanics developed, classical finite-state models naturally played a fundamental role, since only the finite-state character of the microscopic substratum normally enters into the macroscopic counting. Given more than a century of finite-state underpinnings, one might have expected that by now all of physics would be based on informational and computational concepts. That this isn't so may simply reflect the stubborn legacy of the continuum, and the recency and macroscopic character of computer science. In this paper, I discuss the origins of informational concepts in physics, and reexamine computationally some fundamental dynamical quantities. 相似文献