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1.
Clear windows onto emergent hadron mass(EHM)and modulations thereof by Higgs boson interactions are provided by observable measures of pion and kaon structure,many of which are accessible via generalised parton distributions(GPDs).Beginning with algebraic GPD Ans?tze,constrained entirely by hadron-scaleπand K valence-parton distribution functions(DFs),in whose forms both EHM and Higgs boson influences are manifest,numerous illustrations are provided.They include the properties of electromagnetic form factors,impact parameter space GPDs,gravitational form factors and associated pressure profiles,and the character and consequences of allorders evolution.The analyses predict that mass-squared gravitational form factors are stiffer than electromagnetic form factors;reveal that K pressure profiles are tighter than profiles,with both mesons sustaining near-core pressures at magnitudes similar to that expected at the core of neutron stars;deliver parameter-free predictions for and K valence,glue,and sea GPDs at the resolving scale l=2GeV;and predict that at this scale the fraction of meson mass-squared carried by glue and sea combined matches that lodged with the valence degrees-of-freedom,with a similar statement holding for mass-squared radii.  相似文献   

2.
The subsolidus phase relations of a ZnO-V 2 O 5-K 2 O system are investigated by X-ray powder diffraction.There is 1 ternary compound,11 binary compounds and 14 three-phase regions in this system.The phase diagrams of V 2 O 5 K 2 O with the K 2 O content ranging from 0 to 71 mol% and pseudo-binary system of ZnO-K 2 ZnV 2 O 7 are also studied by X-ray powder diffraction and differential thermal analysis methods.  相似文献   

3.
Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-order nonlinear Schr?dinger system, which is discussed in this paper. For such a system, we work out the Lax pair, Darboux transformation, and corresponding vector semi-rational nonautonomous rogue wave solutions. When the group velocity dispersion(GVD) and fourth-order dispersion(FOD) coefficients are the constants, we exhibit the first-and second-order vector semirational rogue waves which are composed of the four-petalled rogue waves and eye-shaped breathers. Both the width of the rogue wave along the time axis and temporal separation between the adjacent peaks of the breather decrease with the GVD coefficient or FOD coefficient. With the GVD and FOD coefficients as the linear, cosine, and exponential functions, we respectively present the first-and second-order periodic vector semi-rational rogue waves, first-and second-order asymmetry vector semi-rational rogue waves, and interactions between the eye-shaped breathers and the composite rogue waves.  相似文献   

4.
Gamal G.L.Nashed 《中国物理 B》2012,21(6):60401-060401
A perfect fluid with self-similarity of the second kind is studied within the framework of the teleparallel equivalent of general relativity(TEGR).A spacetime which is not asymptotically flat is derived.The energy conditions of this spacetime are studied.It is shown that after some time the strong energy condition is not enough to satisfy showing a transition from standard matter to dark energy.The singularities of this solution are discussed.  相似文献   

5.
乔明  庄翔  吴丽娟  章文通  温恒娟  张波  李肇基 《中国物理 B》2012,21(10):108502-108502
Based on the theoretical and experimental investigation of a thin silicon layer(TSL) with linear variable doping(LVD) and further research on the TSL LVD with a multiple step field plate(MSFP),a breakdown voltage(BV) model is proposed and experimentally verified in this paper.With the two-dimensional Poisson equation of the silicon on insulator(SOI) device,the lateral electric field in drift region of the thin silicon layer is assumed to be constant.For the SOI device with LVD in the thin silicon layer,the dependence of the BV on impurity concentration under the drain is investigated by an enhanced dielectric layer field(ENDIF),from which the reduced surface field(RESURF) condition is deduced.The drain in the centre of the device has a good self-isolation effect,but the problem of the high voltage interconnection(HVI) line will become serious.The two step field plates including the source field plate and gate field plate can be adopted to shield the HVI adverse effect on the device.Based on this model,the TSL LVD SOI n-channel lateral double-diffused MOSFET(nLDMOS) with MSFP is realized.The experimental breakdown voltage(BV) and specific on-resistance(R on,sp) of the TSL LVD SOI device are 694 V and 21.3 ·mm 2 with a drift region length of 60 μm,buried oxide layer of 3 μm,and silicon layer of 0.15 μm,respectively.  相似文献   

6.
王月媛  刘正君  廖庆洪  刘树田 《中国物理 B》2010,19(5):54204-054204
Phase properties of the even and odd circular states are studied within the Hermitian phase formalism of Pegg and Barnett. Exact analytical formulas for the distribution function and the variance of the phase operator are obtained and used to examine whether or not the even and odd circular states exhibit photon-number squeezing and phase squeezing.  相似文献   

7.
程玉民  王健菲  白福浓 《中国物理 B》2012,21(9):90203-090203
In this paper, based on the element-free Galerkin (EFG) method and the improved complex variable moving least- square (ICVMLS) approximation, a new meshless method, which is the improved complex variable element-free Galerkin (ICVEFG) method for two-dimensional potential problems, is presented. In the method, the integral weak form of control equations is employed, and the Lagrange multiplier is used to apply the essential boundary conditions. Then the corresponding formulas of the ICVEFG method for two-dimensional potential problems are obtained. Compared with the complex variable moving least-square (CVMLS) approximation proposed by Cheng, the functional in the ICVMLS approximation has an explicit physical meaning. Furthermore, the ICVEFG method has greater computational precision and efficiency. Three numerical examples are given to show the validity of the proposed method.  相似文献   

8.
In the present work,we used five different versions of the quark-meson coupling(QMC)model to compute astrophysical quantities related to the GW170817 event and the neutron star cooling process.Two of the models are based on the original bag potential structure and three versions consider a harmonic oscillator potential to confine quarks.The bag-like models also incorporate the pasta phase used to describe the inner crust of neutron stars.With a simple method studied in the present work,we show that the pasta phase does not play a significant role.Moreover,the QMC model that satisfies the GW170817 constraints with the lowest slope of the symmetry energy exhibits a cooling profile compatible with observational data.  相似文献   

9.
The quantum private query(QPQ)is a quantum solution for the symmetrically private information retrieval problem.We study the security of quantum-key-distribution-based QPQ with weak coherent pulses.The result shows that multiphoton pulses have posed a serious threat to the participant’s privacy in QPQ protocols.Then we propose a decoy-state method that can help the honest participant detect the attack by exploiting multiphoton pulses and improving the key distillation process to defend against such attack.The analysis demonstrates that our decoy-state method significantly improves the security of the QPQ with weak coherent pulses,which solves a major obstacle in the practical application of the QPQ.  相似文献   

10.
The spin structure of nucleons is presented in the framework of an extended quark model which in addition to the conventional qqq structure also takes into account qqqq admixtures in the nucleon wave functions, where the qqqq components are in colored quark cluster configurations. The axial vector weak coupling constant and spin distributions for polarized nucleons as well as spin content are obtained for the lowest positive parity qqqq configurations in flavor-spin dependent interaction. In particular, the contributions of the down and strange quarks to the proton spin and the sum rule for polarized neutron are negative, in agreement with recent experiments.  相似文献   

11.
The real physics models are usually quite complex with some arbitrary parameters which will lead to the nonintegrability of the model.To find some exact solutions of a nonintegrable model with some arbitrary parameters is much more difficult than to find the solutions of a model with some special parameters.In this paper,we make a modification for the usual direct method to find some conditional similarity solutions of a (2 1)-dimensional general nonintegrable KdV equation.  相似文献   

12.
宇宙线对地球气候的影响   总被引:4,自引:2,他引:2  
对宇宙线影响地球气候的一些观测结果和物理机制的研究进行了总结和概述,主要讨论了宇宙线对大气中化学反应、云形成过程等的影响,并给出了羊八井宇宙线观测站对宇宙线流强和大气参量日变化的初步观测结果.  相似文献   

13.
王欢  李彪 《中国物理 B》2011,20(4):40203-040203
In this paper,we investigate some exact soliton solutions for a generalized variable-coefficients nonlinear Schrdinger equation (NLS) with an arbitrary time-dependent linear potential which describes the dynamics of soliton solutions in quasi-one-dimensional Bose-Einstein condensations. Under some reasonable assumptions,one-soliton and two-soliton solutions are constructed analytically by the Hirota method. From our results,some previous one-and two-soliton solutions for some NLS-type equations can be recovered by some appropriate selection of the various parameters. Some figures are given to demonstrate some properties of the one-and the two-soliton and the discussion about the integrability property and the Hirota method is given finally.  相似文献   

14.
In the present work we analyze the possibility of detecting some deformed dispersion relations, emerging in some quantum-gravity models, resorting to the so-called Hanbury–Brown–Twiss effect. It will be proved that in some scenarios the possibilities are not pessimistic. Forsooth, for some values of the corresponding parameters the aforementioned effect could render interesting outcomes.  相似文献   

15.
In the present paper, we review some recent results about commutative positive operator valued measures (POVMs) and single out some open problems. We introduce a conjecture about the extension of some recent results and prove some important consequences of such conjecture. In particular, we prove that it implies the universal character of some of the mathematical objects we introduce, i.e., the fact that they do not depend on the POV measure we are considering. We analyze the relevance of this result. Finally, we point out that some of the results we present admit a constructive proof and we show the relevance of this fact to the theory of commutative POV measures.  相似文献   

16.
非线性热声理论的研究进展   总被引:4,自引:0,他引:4  
主要总结了热声系统中的非线性热声现象,指出了线性热声理论的不足,回顾了近十年来国内外热声工作者为解释这些非线性现象所做的理论探索,对其发展方向进行了展望.  相似文献   

17.
光学系统偏心测量原理及应用   总被引:6,自引:1,他引:5  
综述了光学系统偏心测试研究方面的发展概况及目前所达到的水平。简要介绍了光学系统偏心测量及基准轴变换原理,并讨论了一些必要的问题。最后介绍了测量方法的一些具体应用,指出了一些测量中应注意的问题和技巧,并介绍了几个具有代表性的,经过多年实践创造出来的应用方法实例。  相似文献   

18.
A. Sharma 《Pramana》2003,60(5):865-875
Gaseous detectors have been pushed to the limits when required to operate in the ferocious and aggressive rate environment of the new generation of HEP experiments. A great effort has resulted in the optimization and construction of large systems of gas detectors, some operational and some due for installation. In this paper some examples are presented along with the impediments that have been overcome; some open issues will be highlighted.  相似文献   

19.
杜勇  方炎 《光散射学报》2003,15(3):131-138
比较了染料分子结晶紫(CV)在酸性与中性条件下的金胶体系中的近红外表面增强拉曼光谱(NIR-SERS)。结果表明,结晶紫分子-金胶体系中结晶紫分子在1064nm近红外光激发条件下,其荧光得以大大淬灭,同时拉曼得到了至少不低于105倍的增强;当进一步加入硝酸使得其处于酸性气氛下时,由于部分结晶紫分子与硝酸发生了化学作用形成了结晶紫分子的单替代衍生物(HCV),而HCV与结晶紫分子相比,更容易吸附在金属表面,因此结晶紫分子NIR-SERS还将有很大的增强。这可以给我们很大的启示:改变体系的酸碱度也可以达到改变其SERS的增强效果的目的。  相似文献   

20.
We compute the transgressed forms of some modularly invariant characteristic forms, which are related to the twisted elliptic genera. We study the modularity properties of these secondary characteristic forms and relations among them. We also get some twisted anomaly cancellation formulas on some odd dimensional manifolds.  相似文献   

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