Modification of gravitational redshift of x-ray burst produced by pulsar surface magnetoplasma

In this paper, the propagation of x-ray bursts in the magnetoplasma of pulsar magnetosphere is discussed. The electromagnetic interaction between x-ray bursts and magnetoplasma is described as some geometry. The electromagnetic effects of surface superstrong magnetic field and dynamic effects of outflowing magnetoplasma of pulsars are treated as an optical metric. The Gordon metric is introduced to represent the gravitational metric and optical metric. So the propagation of x-ray bursts in magnetoplasma of pulsars can be described as x-ray bursts transmitting in an effective space characterized by Gordon metric. The modification of gravitational redshift, attributed to the flowing magnetoplasma of pulsars, is obtained and it is shown that the modification is of redshift and can reach the same magnitude as the gravitational redshift for ordinary pulsars.     

Modified surface redshift of pulsars produced by magnetoplasma

The propagation of photons in the magnetoplasma medium of pulsar magnetosphere is studied in the framework of an effective metric theory. It is found that the surface redshift is induced by two factors: one coming from the gravitational field and another from the magnetoplasma. The magnetoplasma can shift the spectrum, and the modification of surface redshift of pulsars due to associated magnetoplasma can be the same extent as the gravitational redshift in particular cases via calculation.     

利用爱因斯坦转盘推求中心引力场中的光频红移--在普通物理教学中讲解等效原理的一种尝试

通过球对称引力场与爱因斯坦转盘上的惯性离心力场的对比，利用强等效原理导出光频的引力红移。     

Strong gravitational lensing for photon coupled to Weyl tensor in Kiselev black hole

The objective of the present work is to highlight the phenomena of strong gravitational lensing and deflection angle for the photon coupling with the Weyl tensor in a Kiselev black hole. Here, we have extended the prior work of Chen and Jing (S. Chen and J. Jing, JCAP, 10: 002 (2015)) for a Schwarzschild black hole to a Kiselev black hole. For this purpose, the equation of motion for the photons coupled to the Weyl tensor, null geodesic, and equation of photon sphere in a Kiselev black hole spacetime have been formulated. It is found that the equation of motion of the photons depends not only on the coupling between the photons and the Weyl tensor, but also on the polarization direction of the photons. There is a critical value of the coupling parameter, \begin{document}$ \alpha$\end{document} , for the existence of the marginally circular photon orbit outside the event horizon, which depends on the parameters of the black hole and the polarization direction of the photons. Further, the polarization directions of the coupled photons and the coupling parameter, \begin{document}$ \alpha$\end{document}; both modify the features of the photon sphere, angle of deflection, and functions \begin{document}$ (\bar{a}$\end{document} and \begin{document}$ \bar{b})$\end{document} owing to the strong gravitational lensing in the Kiselev black hole spacetime. In addition to this, the observable gravitational lensing quantities and the shadows of the Kiselev black hole spacetime are presented in detail.     

A Possible Modification of Einstein's Theory of General Relativity

This article suggests a new metric theory of gravitation, in which metric field is determined not only by matter and nongravitational field but also by vector graviton field, and in principle there is no need to introduce the Einstein's tensor. In order to satisfy automatically the geodesic postulate, an additional coordinate condition is needed.For the spherically symmetric static field, it leads us to quite different conclusions from those of Einstein's general relativity in the interior region of the surface of infinite redshift. Accurate to the first order of GM/r, it obtains the same results about the four experimental tests of general relativity.     

Recognition of gravitation impulses on a correlated non-Gaussian noise background

We consider the problem of gravitation-wave impulse recognition against the background of correlated noise produced by resonance gravitational antennas. A new algorithm for the joint processing of data recorded by spatially separated gravitational detectors is obtained. The algorithm is an alternative to the coincidence scheme, which is traditionally used in gravitation-wave experiments. It is based on the principles, well known in statistical radiophysics, of joint detection and parameter estimation in quasi-deterministic signals.     

双驱动x射线激光等离子体能谱特性研究

用时间积分空间分辨的平晶千电子伏谱仪测量了钽激光等离子体发射波长范围为045— 075nm的软x射线能谱，精确测量和准确辨认出类镍、类钴和类铁离子的共振线及类镍离子 的内壳层跃迁线-对实验结果处理，获得了辐射线谱的强度-通过谱线比率的诊断推断脉冲激 光时差对等离子体状态的影响，至少也可部分解释激光上能级的粒子数及等离子体的 电离程度- 关键词： 离子谱特性 软x线能谱强度 谱线辨认     

等电子法测量小能量激光打靶等离子体电子温度

以低Z的CHO薄膜作为样品靶，在星光激光装置上以小能量激光辐照样品靶产生温度较低的等离子体，采用每毫米2400线的平焦场光栅谱仪测量等离子体发射的碳和氧离子发射谱线强度比，并与理论计算相应线强比较，获得了电子温度，建立了等电子法测量较低温度(100eV左右)等离子体电子温度的诊断技术. 关键词： 电子温度 激光等离子体 等电子x射线谱法     

大尺度有效引力的E(2)规范理论模型

微波背景辐射的低l极矩的各向异性可能不能用微波背景辐射静止系boost到本动参考系来解释,我们推断boost对称性在宇宙学尺度上缺失,又由于单纯结合广义相对论和物质结构的标准模型不能解释星系以上尺度的引力现象,需要引入暗物质和暗能量.而迄今为止所有寻找暗物质粒子的实验给出的都是否定结果,暗能量的本质更是一个谜.因此,我们假设洛伦兹对称性是从星系以上尺度开始部分破缺,以非常狭义相对论对称群E(2)为例,用E(2)规范理论来构造大尺度有效引力理论,并分析了此规范理论的自洽性.从这些讨论中发现,当物质源即使为普通标量物质时,contortion也一般非零,非零contortion的存在会贡献一个等效能量动量张量的分布,它可能对暗物质效应给出至少部分的贡献.我们从对称性出发修改引力,有别于其他的修改引力理论.     

X-ray absorption near the edge structure and x-ray photoelectron spectroscopy studies on pyrite prepared by thermally sulfurizing iron films

This paper reports how pyrite films were prepared by thermal sulfurization of magnetron sputtered iron films and characterized by x-ray absorption near edge structure spectra and x-ray photoelectron spectroscopy on a 4B9B beam line at the Beijing Synchrotron Radiation Facility. The band gap of the pyrite agrees well with the optical band gap obtained by a spectrophotometer. The octahedral symmetry of pyrite leads to the splitting of the d orbit into t_{\rm 2g} and e_{\rm g} levels. The high spin and low spin states were analysed through the difference of electron exchange interaction and the orbital crystal field. Only when the crystal field splitting is higher than 1.5 eV, the two weak peaks above the white lines can appear, and this was approved by experiments in the present work.     

Scaling of x-ray emission and ion velocity in laser produced Cu plasmas

The x-ray emission from slab targets of copper irradiated by Nd:glass laser (1.054 μm, 5 and 15 ns) at intensities between 10¹² and 10¹¹W/cm² has been studied. The x-ray emissions were monitored with the help of high quantum efficiency x-ray silicon photo diodes and vacuum photo diodes, all covered with aluminium filters of different thickness. The x-ray intensity vs the laser intensity has a scaling factor of (1.2–1.92). The relative x-ray conversion efficiency follows an empirical relationship which is in close agreement with the one reported by Babonneau et al. The ion velocities were monitored using Langmuir probes placed at different angles and radial distances from the target position. The variation of the ion velocity with the laser intensity follows a scaling of the form Φ ^β where β ∼0.22 which is in good agreement with the reported scaling factor values. The results on the x-ray emission from Cu plasma are reported.     

A study of Fermi level shifts in copper-gallium and copper-germanium alloys by x-ray absorption spectroscopy

The K x-ray absorption discontinuities of copper, gallium and germanium in pure metals as well as in six copper-gallium and three copper-germanium alloys have been studied using a Cauchois-type bent crystal spectrograph. It is observed that in all the systems the K discontinuity of copper shifts towards the higher energy side, while the discontinuities of gallium and germanium shift to the lower energy side relative to their positions in the respective pure metals. The magnitudes of the shifts are found to increase with the decrease in the content of the absorbing atom in the alloys. The observed shifts are explained on the basis of the free-electron theory of metals and the rigid-band model for alloys.     

Effects on the Structure of the Universe of an Accelerating Expansion

Recent experimental results from supernovae Ia observations have been interpreted to show that the rate of expansion of the universe is increasing. Other recent experimental results find strong indications that the universe is flat. In this paper, I investigate some solutions of Einstein's field equations which go smoothly between Schwarzschild's relativistic gravitational solution near a mass concentration to the Friedmann-Lemaître expanding universe solution. In particular, the static, curved-space extension of the Lemaître-Schwarzschild solution in vacuum is given. Uniqueness conditions are discussed. One of these metrics preserves the cosmological equation. We find that when the rate of expansion of the universe is increasing, space is broken up into domains of attraction. Outside a domain of attraction, the expansion of the universe is strong enough to accelerate a test particle away from the domain boundary. I give a domain-size–mass relationship. This relationship may very well be important to our understanding of the large scale structure of the universe.     

光线在恒星表面附近传播的偏折角

光线在恒星附近传播时,理论计算的偏折角有两个结果.一个结果由Newton引力论计算而得,另一个由Einstein广义相对论计算得到.后者是前者的两倍.对于与人类最近的恒星太阳,数值计算结果分别为0.875″(角秒)和1.75″,本文给出这两个结果的详细计算过程.日食发生时是检测理论结果的良好时机,迄今为止所有的实验观测结果支持相对论对太阳光线偏折角的计算.     

Multiple expansions for energy and momenta carried by gravitational waves

We present expressions for the energy, linear momentum and angular momentum carried away from an isolated system by gravitational radiation based on spin-weighted spherical harmonics decomposition of the Weyl scalar Ψ ₄. We also show that the expressions derived are equivalent to the common expressions obtained when using a framework based on perturbations of a Schwazschild background. The main idea is to collect together all the different expressions in a uniform and consistent way. The formulae presented here are directly applicable to the calculation of the radiated energy, linear momentum and angular momentum starting from the gravitational waveforms which are typically extracted from numerical simulations. An erratum to this article can be found at     

Transition metal oxide perovskites by photoelectron and x-ray absorption spectroscopy

X-ray and ultraviolet photoelectron spectroscopy as well as x-ray absorption spectroscopy have been employed to investigate transition metal oxide perovskites of the general formula ABO₃ (A = La or rare-earth ion, B=trivalent transition metal ion). Systematics in the core levels and in the valence bands in the series of LaBO₃ compounds have been discussed. Lanthanum chemical shifts in the x-ray absorption spectra in this series show interesting trends. Photoelectron spectra of the solid solutions, LaNi_1−x Co _x O₃, LaNi_1−x Fe _x O₃ and LaFe_1−x Co _x O₃ show that the rigid band model is applicable to these systems. It is shown that x-ray photoelectron spectroscopy can be employed to identify multiple oxidation states of transition metal ions in oxide perovskites. Communication No. 30 from the Solid State and Structural Chemistry Unit. An erratum to this article is available at .     

Mysteries of R^ik=0： A novel paradigm in Einstein＇s theory of gravitation

Despite a century-long effort, a proper energy-stress tensor of the gravitational field, could not have been discovered. Furthermore, it has been discovered recently that the standard formulation of the energy-stress tensor of matter, suffers from various inconsistencies and paradoxes, concluding that the tensor is not consistent with the geometric formulation of gravitation [Astrophys. Space Sci., 2009, 321： 151; Astrophys. Space Sei., 2012, 340： 373]. This perhaps hints that a consistent theory of gravitation should not have any bearing on the energy-stress tensor. It is shown here that the so-called ＂vacuum＂ field equations Rik = 0 do not represent an empty spacetime, and the energy, momenta and angular momenta of the gravitational and the matter fields are revealed through the geometry, without including any formulation thereof in the field equations. Though, this novel discovery appears baffling and orthogonal to the usual understanding, is consistent with the observations at all scales, without requiring the Moreover, the resulting theory circumvents the besides explaining some unexplained puzzles. hypothetical dark matter, dark energy or inflation long-standing problems of the standard cosmology     

掠入射驱动产生x射线激光的数值模拟

利用一维流体力学数值模拟程序MEDUSA和原子物理程序包，以类镍钼189nm x射线激光为例，对掠入射驱动x射线激光方案进行了研究.掠入射驱动x射线激光方案可以通过调整掠入射角来选择适合的增益区间.与正入射驱动方案相比，掠入射驱动方案加强了驱动激光在增益区内的吸收，提高了驱动激光向x射线激光的转换效率.模拟结果与实验结果符合较好. 关键词： x射线激光 掠入射辐照 激光等离子体     

Quintessence and Dark Matter Created by Weyl–Dirac Geometry

A spatially closed universe undergoing at present accelerated expansion, having a non-vanishing cosmological constant, and filled with luminous- and dark matter is described in terms of the Integrable Weyl–Dirac theory. It is shown that, during the dust-dominated period, dark matter and the quintessence pressure, the latter giving rise to acceleration: both are created by the Dirac gauge function. The behavior of two models: a nearly flat one and a well closed are considered in appropriate gauges, and plausible scenarios are obtained. The outcome of the present paper, together with results of a previous work,⁽³¹⁾ provide a geometrically based, classical, singularity-free model of the universe, that has originated from a pure geometric Weyl–Dirac entity, passed a prematter period, the radiation-dominated era, and continues its development in the present dust period.