Neutrino in matter and external fields

A technique for describing various processes proceeding in matter and involving neutrinos and electrons is discussed. This technique is based on “the method of exact solutions,” which implies the use of solutions to proper Dirac equations for particle wave functions in matter. Exact solutions for the neutrino and the electron in the cases of uniform nonmoving and rotating matter are discussed. On studying relativistic neutrino motion and associated neutrino-energy quantization in rotating matter, a semiclassical interpretation of particle finite motion is developed. In the general case of neutrino and electron motion in matter with varying parameters, the corresponding effective force acting on the particles is determined. The possibility of electromagnetic-wave radiation by an electron that moves in a dense neutrino flux of varying density and which is accelerated by this kind of force is predicted.     

Method of kinematic projecting of pulsar-emission profiles

A method for constructing profiles of incoherent pulsar emission based on the instantaneous angular phase distribution function of radiant power emitted by a relativistic source that moves in the magnetosphere of a neutron star is suggested. In general, this phase function depends on the kinematic parameters of the radiation source (its velocity and acceleration) and on the direction of radiation emission with respect to the rotating neutron star (the observation direction). The method is illustrated by the example of calculated profiles of fan pulsar radiation with the use of the phase function of synchrotron radiation. It is stated that his method can easily be generalized for other types of relativistic radiation. Tomsk State University; Tomsk State Pedagogical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 26–31, January, 2000.     

Gauge and gravitational anomalies and Hawking radiation of rotating BTZ black holes

In this paper we obtain the flux of Hawking radiation from rotating BTZ black holes from the gauge and gravitational anomalies point of view. Then we show that the gauge and gravitational anomaly in BTZ spacetime is cancelled by the total flux of a 2-dimensional blackbody at the Hawking temperature of the spacetime.     

Self-similar Solution of a Cylindrical Shock Wave under the Action of Monochromatic Radiation in a Rotational Axisymmetric Dusty Gas

A self-similar flow behind a cylindrical shock wave is studied under the action of monochromatic radiation in a rotational axisymmetric dusty gas. The dusty gas is taken to be a mixture of small solid particles and perfect gas,and solid particles are continuously distributed in the mixture. The similarity solutions are obtained and the effects of the variation of the radiation parameter, the ratio of the density of solid particles to the initial density of the gas, the mass concentration of solid particles in the mixture and the index for the time dependent energy law are investigated.It is observed that an increase in the radiation parameter has decaying effect on the shock waves; whereas the shock strength increases with an increase in the ratio of the density of solid particles to the initial density of the gas or the index for the time dependent energy law. Also, it is found that an increase in the radiation parameter has effect to decrease the flow variables except the density and the azimuthal component of fluid velocity. A comparison is also made between rotating and non-rotating cases.     

跨音压气机转子叶尖间隙复杂流动观测

本文利用高频响动态压力传感器,在文献［１］的基础上,对ＷＰ１１压气机转子叶尖间隙 流场进行了流场测量。测试包括三个转速多个节流条件下的间隙流场。测试结果表明：激波总体位 置随节流加深而向上游移动,但吸力面最小压力点基本维持在４０％或２０％弦长处不变。当激波位 置在该点之后时,二次漏流直接冲击激波结构;当激波位置在该点之前时,激波结构基本只受前缘 漏流的影响。     

Jet-Quenching of the Rotating Heavy Meson in a ${\mathcal{N}}=4$ SYM Plasma in Presence of a Constant Electric Field

In this paper, we consider a rotating heavy quark-antiquark (q[`(q)]q\bar{q}) pair in a N=4{\mathcal{N}}=4 SYM thermal plasma. We assume that q[`(q)]q\bar{q} center of mass moves at the speed v and furthermore they rotate around the center of mass. We use the AdS/CFT correspondence and consider the effect of external electromagnetic field on the motion of the rotating meson. Then we calculate the jet-quenching parameter corresponding to the rotating meson in the constant electric field.     

Mass Flux Schemes and Connection to Shock Instability

We analyze numerical mass fluxes with an emphasis on their capability for accurately capturing shock and contact discontinuities. The study of mass flux is useful because it is the term common to all conservation equations and the numerical diffusivity introduced in it bears a direct consequence to the prediction of contact (stationary and moving) discontinuities, which are considered to be the limiting case of the boundary layer. We examine several prominent numerical flux schemes and analyze the structure of numerical diffusivity. This leads to a detailed investigation into the cause of certain catastrophic breakdowns by some numerical flux schemes. In particular, we identify the dissipative terms that are responsible for shock instabilities, such as the odd–even decoupling and the so-called “carbuncle phenomenon”. As a result, we propose a conjecture stating the connection of the pressure difference term to these multidimensional shock instabilities and hence a cure to those difficulties. The validity of this conjecture has been confirmed by examining a wide class of upwind schemes. The conjecture is useful to the flux function development, for it indicates whether the flux scheme under consideration will be afflicted with these kinds of failings. Thus, a class of shock-stable schemes can be identified. Interestingly, a shock-stable scheme's self-correcting capability is demonstrated with respect to carbuncle-contaminated profiles for flows at both low supersonic and high Mach numbers.     

转捩与湍流对激波边界层干扰及底部流动结构的影响

为研究转捩与湍流对激波边界层干扰及底部流动结构的影响,文章选取了二维与三维高超声速双斜面进气道模型与大钝头着陆器模型,并使用γ-Re_θ转捩模型开展数值模拟研究.研究表明,对于二维进气道模型,随着前缘钝度的增加,激波边界层干扰位置前移,分离区变大,与层流流动情况相比,有转捩流动发生时,激波边界层干扰位置后移,同时分离流动强度变弱,分离区缩小;对于三维进气道模型,其拐角附近的分离流动呈现明显的三维特征,转捩流动也存在三维流动结构,与静风洞状态相比,噪音风洞状态下,有转捩流动发生,对壁面热流影响较大,对激波系影响很小.对于着陆器模型,底部流动发生转捩,使得底部流动由不稳定非定常的流动结构变为稳定定常的流动结构,这有益于姿态控制设计.      

神光Ⅱ上柱形黑腔辐射驱动冲击波

利用神光Ⅱ的八路三倍频激光装置，驱动柱形黑腔产生的x 射线作辐射源驱动台阶铝样品产生冲击波，获得了清晰的冲击波图像，通过冲击波过台阶样 品的时间差获得冲击波速度和压力分别为31.2km/s和17.5×10⁵MPa.采用软x射线能谱 仪通过激光注入孔测量的辐射温度与采用冲击波法测量辐射温度的结果一致. 关键词： 冲击波 辐射驱动 辐射温度     

UV induced photoluminescence and thermally stimulated luminescence of ThO2:Tb3+ phosphor

Thorium oxide doped with trivalent terbium ions offers itself as a novel phosphor with its photo- and thermally-stimulated luminescence (PL and TSL) characteristics showing a marked change on sustained exposure to 254 and 365 nm ultraviolet (UV) radiation. The reduction in luminescence intensity of Tb³⁺ ions, on irradiation with 254 nm photons and subsequent restoration on exposure to 365 nm, has been correlated with the complimentary behaviour in UV-induced TSL. These changes are, in turn, ascribed to inter-configurational (f–d) transitions and e–h formation and recombination processes. UV radiation induced TSL output increases linearly with incident UV radiant energy at a constant radiation flux; however, for a fixed exposure, TSL output increases with increase in radiant flux.     

A miniature closed‐circle flow cell for high photon flux X‐ray scattering experiments

A closed‐circle miniature flow cell for high X‐ray photon flux experiments on radiation‐sensitive liquid samples is presented. The compact cell is made from highly inert material and the flow is induced by a rotating magnetic stir bar, which acts as a centrifugal pump inside the cell. The cell is ideal for radiation‐sensitive yet precious or hazardous liquid samples, such as concentrated acids or bases. As a demonstration of the cell's capabilities, X‐ray Raman scattering spectroscopy data on the oxygen K‐edge of liquid water under ambient conditions are presented.     

Hawking radiation of five-dimensional rotating black hole

Applying the Damour–Ruffini method, we have considered the Hawking radiation of the five-dimensional rotating black hole. When taking the energy conservation and angular momentum conservation into consideration and considering the reaction of the radiation of the particle to spacetime, we see that the exact radiation spectrum is not purely thermal and the angular momentum of the black hole is quantized.     

Results of the search for strange quark matter and Q-balls with the SLIM experiment

The SLIM experiment at the Chacaltaya high altitude laboratory was sensitive to nuclearites and Q-balls which could be present in the cosmic radiation as possible Dark Matter components. It was sensitive also to strangelets, i.e. small lumps of Strange Quark Matter predicted at such altitudes by various phenomenological models. The analysis of 427 m² of Nuclear Track Detectors exposed for 4.22 years showed no candidate event. New upper limits on the flux of downgoing nuclearites and Q-balls at the 90% C.L. were established. The null result also restricts models for strangelets propagation through the Earth atmosphere.     

Model of pulsed electric discharge expansion in dense gas taking into account electron and radiative thermal conductivities. I. Expansion mechanism

Using an ionization sensor, it was found that weakly ionized plasma with an ionization degree larger than 10^?6 is formed under exposure to UV radiation of a high-current pulsed electric discharge in gas (air, nitrogen, xenon, and krypton) at atmospheric pressure at a distance of ～1.2–2.5 cm from the discharge boundary. It was shown that the structure of such discharge includes, in addition to the discharge channel, a dense shell and a shock wave, also a region of weakly ionized and excited gas before the shock wave front. The mechanism of discharge expansion in dense gas is ionization and heating of gas involved in the discharge due to absorption of the UV energy flux from the discharge channel and the flux of the thermal energy transferred from the discharge channel to the discharge shell due to electron thermal conductivity.     

Model of pulsed electric discharge expansion in dense gas taking into account electron and radiative thermal conductivities. II. Energy balance and equation

Using an ionization sensor, it was found that weakly ionized plasma with an ionization degree larger than 10⁻⁶ is formed under exposure to UV radiation of a high-current pulsed electric discharge in gas (air, nitrogen, xenon, and krypton) at atmospheric pressure at a distance of ∼1.2–2.5 cm from the discharge boundary. It was shown that the structure of such discharge includes, in addition to the discharge channel, a dense shell and a shock wave, also a region of weakly ionized and excited gas before the shock wave front. The mechanism of discharge expansion in dense gas is ionization and heating of gas involved in the discharge due to absorption of the UV energy flux from the discharge channel and the flux of the thermal energy transferred from the discharge channel to the discharge shell due to electron thermal conductivity.     

Can a Wormhole Generate Electromagnetic Field?

We have considered the possibility of a rotating wormhole surrounded by a cloud of charged particles. Due to slow rotation of the wormhole, the charged particles are dragged, thereby producing an electromagnetic field. We have determined the strength of this electromagnetic field and the corresponding flux of radiation.     

Surface charge carrier motion on insulating surfaces: One dimensional motion

We consider a model for the motion of charge carriers on the surface of an insulator. The insulator surface is either infinite, semi–infinite against a conducting half space or a strip between two conducting half spaces. The charge flux on the surface is assumed equal to the charge density times the electric field component in the surface, with time a constant. When the charge carrier motion in the plane is assumed constant in one direction, we can write the problem as an inviscid Burgers equation for a complex function. The imaginary part of this function is minus the carrier density while the real part, the Hilbert transform of the carrier density, is minus the electric field on the surface. Using the method of characteristics, we find an exact implicit solution for the problem and illustrate it with several examples. One set of examples, on the real line, or half of it, show how charge moves and how the surface may discharge into a conducting wall. They also show that the system can sustain shock wave solutions which are different from those in a real Burgers equation and other singular behaviour. Exact solutions on a finite strip between two conducting walls also show how that system can discharge completely, and also demonstrate shock waves. These systems are of particular interest because they are experimentally accessible.     

CH薄膜非平衡辐射烧蚀的特性

 用一维多群辐射输运流体力学RDMG程序数值模拟研究了在神光-II黑腔辐射源条件下，非平衡辐射烧蚀CH薄膜的过程，给出了与平衡辐射烧蚀不同的烧蚀图像，得到了非平衡辐射烧蚀相关的数值定律。