Oscillations of Magnetic Fluid Column in Strong Magnetic Field

Russian Physics Journal - The paper considers the results of measuring the elastic parameters (ponderomotive elasticity coefficient, oscillation frequency, attenuation coefficient) of the...     

Lepton-Lepton Interactions under a Strong Magnetic Field

The cross-section for the reaction e⁺ + e^? → v + v , under a strong magnetic field is calculated. The rate of energy loss is also calculated. These calculations may be of great importance for astrophysical estimations in neutron stars.     

水基自形成CoFe2O4 磁性液体的零磁场粘滞特性

在零磁场下 ,水基自形成CoFe2 O4磁性液体粘度 η与CoFe2 O4纳米微粒体积分数Φ显示出特异的关系 ,然而 ,球形刚性粒子填料悬浮液粘度理论不能很好解释 .通过对水基自形成CoFe2 O4磁性液体中的微粒相互作用分析发现 ,此磁性液体的沉降和在磁场中的成链需有以预团聚体为核的大粒子存在 .在这一基础上 ,建立了团聚涨落模型 .于是 ,平均粒径、Einsten系数和粒径分布偏差均成为微粒体积分数的函数 ,也即对Popplewell粘度公式的修正 .最后得到与实验很好吻合的 η～Φ曲线及关系式 .     

高强度磁场中氢原子性态的研究

采用变分法和微扰法相结合的方法 ,把高强度磁场中氢原子的哈密顿H分为三部分 :球对称哈密顿 ;z分量角动量算符相应部分和非球对称势微扰 ,并用一种特别规定的分解法将哈密顿H中含磁场平方项的势能分解为球对称与非球对称两部分 ,且使非球对称部分引起的一级修正能量值为零 ,并采用一种简便的变分法直接求出B2 对能级的二级修正值 .这一方法不仅计算简单 ,而且提高了计算结果的精度 .计算了在均匀高强度静磁场下氢原子的 11个低能态能级和平均半径 ,讨论了高强度磁场对能级和半径的影响. In this paper we separate the Hamiltonian into three parts: a spherical symmetry Hamiltonian; a z-component of the angular momentum operator, and a non-spherical symmetric potential as the perturbation operator, and provide a propose method by separating the potential containing squared magnetic field B 2 into two parts: spherical symmetric and non-spherical symmetric ones so that the first-order energy correction due to the non-spherical symmetric potential is zero...     

Hadron Polarization in Strong Magnetic Field

Physics of Particles and Nuclei Letters - The magnetic dipole polarizabilities and hyperpolarizabilities of the vector $${{rho }^{0}}$$ and $${{rho }^{ pm }}$$ mesons have been calculated. The...     

磁场中夸克物质的黏滞系数

研究了磁场中夸克非轻子弱作用过程的反应率和黏滞系数. 改进了在弱磁场情况下的近似计算方法, 给出了非轻子过程的反应率与夸克物质的体黏滞系数的表达式, 显示出在弱磁场情况下, 黏滞系数的温度依赖关系与零磁场情况下一致, 但黏滞系数的大小依赖磁场的强度.     

Non-Relativistic H2 +-Molecule in a Strong Magnetic Field

We show that under the influence of a strong uniform magnetic field the energy of the H₂⁺-ion at the 0-th order Born-Oppenheimer approximation goes over into that of the corresponding united atom limit, He⁺.     

Strange Quark Matter and Strangelets in a Strong Magnetic Field

We study the stability properties of magnetized strange quark matter and strangelets under a strong magnetic field in the MIT bag model. The free energy per baryon of strange quark matter feels a great influence from the magnetic field. At the field strength about 10¹⁷G, the magnetized strange quark matter becomes more stable. Considering the finite size effect, the magnetic influence on strangelets becomes complicated. For a given magnetic field, there exists a critical baryon number, below which the magnetized strangelets have lower energy than the non-magnetized strangelets. For the field strength of 5× 10¹⁷G, the critical baryon number is A_c ～ 100. Generally, the critical baryon number increases with the decreasing external magnetic field. When the field strength is smaller than 10¹⁷G, the critical baryon number goes up to A_c～ 10⁵. The stable radius, electric charge, and quark flavor fractions of magnetized strangelets are shown.     

Linear and Nonlinear Magnetic Electron Drift Waves in a Nonuniform Strong Magnetic Field

Linear and nonlinear propagation of magnetic electron drift vortex waves in a nonuniform magnetic field is investigated by means of a generalized adiabatic law which takes into account the effect of strong fields and reduces in the appropriate limits to several well known energy conservation equations in a collisionless plasma. In the linear limit, an instability is shown to exist, whereas in the nonlinear regime, steady-state dipole vortices associated with the electron drift vortex waves may appear. The anomalous electron energy transport associated with the unstable magnetic electron drift vortex waves is investigated by means of a quasilinear theory.     

Dynamic Effects in a Magnetic Fluid with Microdrops of Concentrated Phase in a Rotating Magnetic Field

Technical Physics - Variation in the shape of microdrops of a highly concentrated magnetic colloid resulting from phase separation in a magnetic fluid has been studied. It has been found that even...     

Heat Diffusion across a Strong Stochastic Magnetic Field in Tokamak Plasmas

We investigate heat diffusion across a local strong stochastic magnetic field by using eleven low-m perturbed magnetic islands. A maximum stochasticity of 38.82 between two neighboring rational surfaces is attained. The correlation between the effective radial heat conductivity xτ and the ratio of the parallel heat diffusion coefficient to the perpendicular coefficient, χⅡ/χ⊥, is numerically studied and compared with earlier work.     

Pion and σ-meson Properties in a Strong Magnetic Field

With the Nambu-Jona-Lasinio (NJL) model we calculate the properties of pion and σ-meson at finite temperature and finite magnetic field. The obtained temperature and magnetic field strength dependence of the constituent quark mass M, the pion and σ-meson masses and the neutral pion decay constant indicates that, in the simple four fermion interaction model, there exists the magnetic catalysis effect. It also shows that the Gell-Mann-Oakes-Renner relation is violated obviously with the increasing of the temperature, and the effect of the magnetic field becomes pronounced only around the critical temperature. The deviation of the critical temperatures obtained with different criteria indicates that the chiral phase transition driven by the temperature in the magnetic field strength region we have considered is in fact a crossover.     

Calculation of Excited States of He Atoms in a Strong Magnetic Field

A recently developed B-spline algorithm is extended and utilized to calculate excited states of He atoms in the presence of strong magnetic fields. Binding energies are presented for He in the five excited atomic states 2¹0⁺, 1¹0^-, 2¹0^-, 1¹(-1)⁺, and 2¹(-1)⁺ with magnetic field strength ranging from 0.0001 to 10 a.u. The obtained energies are compared with available theoretical data, and found to be in good agreement. We investigate influence of magnetic fields on atomic structures of multielectron atoms, and illustrate that how electron probability density distributions change with increasing magnetic field strength. The current approach is directly applicable to simulations of discrete spectra for He atoms in the atmospheres of magnetized white dwarf stars.     

强磁场下精细网型光电倍增管的性能测试

北京谱仪升级后(BESⅢ)的飞行时间计数器(TOF)将使用精细网型光电倍增管(PMT).本工作对日本浜松(Hamamatsu)公司生产的精细网型光电倍增管R5924(FM)的性能在强磁场下进行了测试.测量了PMT在顺、逆磁场方向时相对增益随磁场强度的变化,在1T时,与0磁场相比,相对增益下降约50余倍.测量了不同磁场强度(0,0.5,1T)下,PMT的相对增益随工作电压的变化,在相当宽的工作电压范围内,相对增益随工作电压的变化具有指数关系.通过不同磁场强度下PMT相对增益随工作电压变化趋势的比较,表明PMT打拿极精细网型的特殊构造使二次电子发射系数δ中的因子k小于一般值,且随磁场强度的增强而变小,这是造成强磁场下PMT增益下降的重要原因.     

Cooling Curve of Strange Star in Strong Magnetic Field

In this paper, firstly, we investigate the neutrino emissivity from quark Urca process in strong magnetic field. Then, we discuss the heat capacity of strange stars in strong magnetic field. Finally, we give the cooling curve in strong magnetic field. In order to make a comparison, we also give the corresponding cooling curve in the case of null magnetic field. It turns out that strange stars cool faster in strong magnetic field than that without magnetic field.     

Relaxation and Recombination of Antiprotons and Positrons in a Strong Magnetic Field

Journal of Experimental and Theoretical Physics - A physical model is proposed, which makes it possible to determine the velocity distributions of antihydrogen atoms formed as a result of...     

Cooling Curve of Strange Star in Strong Magnetic Field

In this paper, firstly, we investigate the neutrino emissivity from quark Urca process in strong magnetic field. Then, we discuss the heat capacity of strange stars in strong magnetic field. Finally, we give the cooling curve in strong magnetic field. In order to make a comparison, we also give the corresponding cooling curve in the case of null magnetic field. It turns out that strange stars cool faster in strong magnetic field than that without magnetic field.     

Photoelectric Effect on a Hydrogen Atom in an Extremely Strong Magnetic Field

Russian Physics Journal - The photoelectric effect on a hydrogen atom located in an extremely strong magnetic field is considered. The dependence of the cross section on the angle between the...