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31.
A.H.Tang 《中国物理C(英文版)》2020,44(5):054101-054101-13
In this paper a pair of observables are proposed as alternative ways,by examining the fluctuation of net momentum-ordering of charged pairs,to study the charge separation induced by the Chiral Magnetic Effect(CME)in relativistic heavy ion collisions.They are,the out-of-plane to in-plane ratio of fluctuation of the difference between signed balance functions measured in pair’s rest frame,and the ratio of it to similar measurement made in the laboratory frame.Both observables have been studied with simulations including flow-related backgrounds,and for the first time,backgrounds that are related to resonance's global spin alignment.The two observables have similar positive responses to signal,and opposite,limited responses to identifiable backgrounds arising from resonance flow and spin alignment.Both observables have also been tested with two realistic models,namely,a multi-phase transport(AMPT)model and the anomalous-viscous fluid dynamics(AVFD)model.These two observables,when cross examined,will provide useful insights in the study of CME-induced charge separation. 相似文献
32.
热强子质量的有效手征拉氏量近似 总被引:1,自引:0,他引:1
从再现QCD标度反常的线性化手征拉氏量出发,使用热场动力学理论,计算了单圈近似下强子的热质量,并发现组分夸克质量和标量场质量在单圈近似下比在平均场近似下随温度的增加更快地下降,而在手征极限下,π介子在所有温度保持无质量. 相似文献
33.
扫描近场光学显微镜中两类光纤探针传输特性的研究 总被引:13,自引:1,他引:13
采用局域模式耦合理论,对扫描近场光学显微镜中的两类光纤探针-腐蚀锥和熔拉锥的传输特性进行了比较和分析。给出了光在探针锥中传输时耦合效率的分布情况,以及传输效率随锥长,针尖直径和光波长变化的特性。 相似文献
34.
Structures, spectra and surface topographies of as-deposited and annealed AgOx films have been investigated by an X-ray diffractometer, a spectrophotometer and an atomic force microscopy (AFM). X-ray diffraction and spectrum results show that the as-deposited AgOx films with high oxygen ratios (x≥0.5) are in amorphous states and Ag crystalline particles will separate out after annealed. AFM results show that the film surface will become much rougher and film thickness will increase greatly after annealed due to the decomposition of AgOx with release of oxygen. Static recording results show that two microstructures of the recording marks can be produced: one is the bubble mark at a low recording power and the other is the rupture bubble with an ablated aperture (hole) in the center at a high recording power. Based on the formation of rupture bubble marks, the near-field optical distribution of a focused Gaussian laser beam through a sub-wavelength aperture (200 nm in diameter) has been simulated using finite-difference-time-domain (FDTD) method. Results show that the spot size can be greatly squeezed with still highly transmitted intensity, which may lead to the super-resolution readout. 相似文献
35.
We have recently developed methods for obtaining exact two-point resistance of the complete graph minus N edges. We use these methods to obtain closed formulas of certain trigonometrical sums that arise in connection with one-dimensional lattice, in proving Scott’s conjecture on permanent of Cauchy matrix, and in the perturbative chiral Potts model. The generalized trigonometrical sums of the chiral Potts model are shown to satisfy recursion formulas that are transparent and direct, and differ from those of Gervois and Mehta. By making a change of variables in these recursion formulas, the dimension of the space of conformal blocks of SU(2) and SO(3) WZW models may be computed recursively. Our methods are then extended to compute the corner-to-corner resistance, and the Kirchhoff index of the first non-trivial two-dimensional resistor network, 2×N. Finally, we obtain new closed formulas for variant of trigonometrical sums, some of which appear in connection with number theory. 相似文献
36.
W. Bietenholz 《Fortschritte der Physik》2008,56(2):107-180
We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields. Then we proceed to lattice fermions, where we discuss perfect actions for free fields, for the Gross‐Neveu model and for a supersymmetric spin model. We also consider the extension to perfect lattice perturbation theory, in particular regarding the axial anomaly and the quark gluon vertex function. Next we deal with properties and applications of truncated perfect fermions, and their chiral correction by means of the overlap formula. This yields a formulation of lattice fermions, which combines exact chiral symmetry with an optimisation of further essential properties. We summarise simulation results for these so‐called overlap‐hypercube fermions in the two‐flavour Schwinger model and in quenched QCD. In the latter framework we establish a link to Chiral Perturbation Theory, both, in the p‐regime and in the ϵ‐regime. In particular we present an evaluation of the leading Low Energy Constants of the chiral Lagrangian – the chiral condensate and the pion decay constant – from QCD simulations with extremely light quarks. 相似文献
37.
Pengpeng Ding Zihan Guo Dalong Qi Jiali Yao Chengzhi Jin Ning Xu Zhiling Zhang Yunhua Yao Lianzhong Deng Zhiyong Wang Zhenrong Sun Shian Zhang 《Laser \u0026amp; Photonics Reviews》2024,18(5):2300873
Ultrafast laser pulses with complex spatiotemporal and polarization couplings have shown great application prospects in coherent control, particle acceleration, molecular dynamics excitation, and chiral or anisotropic detection. It is very important to observe the polarization-coupled ultrafast laser pulses for characterizing the performance of laser source and understanding the laser-matter interaction, but there is currently no detection technique that can completely characterize them, including the spatio-, spectral-, and polarimetric-temporal information. In this work, a polarimetric-spectral-sensitive has been compressed ultrafast photography (PS-CUP) to realize the real-time intensity visualization of time-varying polarized (TP) ultrafast laser pulses. PS-CUP can not only distinguish the polarization state of a TP pulse, but also realize the spatio-, spectral- and polarimetric-temporal measurement. To demonstrate the ability of polarization resolving detection, PS-CUP is used to successfully distinguish between the sinistral and dextral TP pulses and measure the angle and degree of linear polarization of a dextral TP pulse, respectively, and the experimental results are highly consistent with theoretical simulations. Owing to the unprecedented multidimensional detection ability, PS-CUP is prospected to provide a powerful tool for the diagnosis of various complex ultrafast laser pulses and the detection of ultrafast chiral optics. 相似文献
38.
聚合反应制备键合型纤维素-三(4-甲基苯基甲酸酯)衍生物类手性固定相 总被引:3,自引:0,他引:3
合成了带有甲基丙烯酰基的纤维素-三(4-甲基苯基甲酸酯)衍生物(CTMB),并通过聚合反应将其键合在具有双键的硅胶表面,得到手性固定相(CSP)。用所得到的CSP对9种对映体化合物(丁苯酞、酮基布洛芬、反-2,3-二苯环氧乙烷、安息香、安息香类似物、托葛尔碱、华法令、4,4′-二甲氧基-5,6,5′,6′-二次甲二氧基-2,2′-羰甲基甲酯联苯、4,4′-二甲氧基-5,6,5′,6′-二次甲二氧基-2-羰甲基甲酯-2′-羰甲基乙酯联苯)进行了拆分。考察了CSP制备过程中甲基丙烯酰氯的用量、键合方式以及硅胶 相似文献
39.
采用电磁场有限元方法,数值模拟了孔径型扫描近场光学显微镜(aperture Scanning Near-field Optical Microscopy,a-SNOM)在照明模式下的工作过程.针对金偶极天线结构,改变天线长度和纳米间隙尺寸,计算了a-SNOM探针孔径的远场辐射速率随探针端面中心坐标变化的扫描曲线,实现了超越a-SNOM探针通光孔径尺寸的天线金属纳米间隙的超分辨测量,对于100nm通光孔径的探针,可分辨最小尺寸为10nm(0.016倍波长)的金属间隙.通过对比金属和介质偶极天线的a-SNOM探针远场辐射速率测量的计算结果,表明天线金属纳米间隙的超分辨测量的实现是由于金属间隙表面等离激元的激发. 相似文献
40.
Positive-parity doublet bands were reported in ~(120)I. Based on these, we discuss the corresponding experimental characteristics, including rotational alignment, and re-examine the corresponding configuration assignment.The self-consistent tilted axis cranking relativistic mean-field calculations indicate that the doublet bands are built on the configuration πh_(11/2)■νh_(11/2)~(-1). By adopting the two quasiparticles coupled with a triaxial rotor model, the excitation energies, energy staggering parameter S(I), B(M1)/B(E2), effective angles, and K plots are discussed and compared with available data. The obtained results support the interpretation of chiral doublet bands for the positive-parity doublet bands in ~(120)I, and hence identify this nucleus as the border of the A ≈ 130 island of chiral candidates. 相似文献