Resonance method of electric-dipole-moment measurements in storage rings

A "resonance method" of measuring the electric dipole moment (EDM) of nuclei in storage rings is described, based on two new ideas: (1) Oscillating particles' velocities in resonance with spin precession, and (2) alternately producing two sub-beams with different betatron tunes--one sub-beam to amplify and thus make it easier to correct ring imperfections that produce false signals imitating EDM signals, and the other to make the EDM measurement.     

Damping of light in a weakly resonant inhomogeneous medium

On the basis of an expression obtained earlier for the permittivity in the form of a series in powers of the atomic polarizability, the mechanism of damping of light caused by the processes of reemission between two atoms is considered. It is shown that, on an increase in the polarizability, as a consequence of the light frequency approaching the resonance frequency, this mechanism leads to a sharp increase in the extinction coefficient. This effect is caused by the collective behavior of the atoms and is not connected with the natural absorption near the resonance.     

Connection between beam polarization and systematical errors in storage ring electric-dipole-moment experiments

Analysis of spin dynamics in storage ring electric-dipole-moment (EDM) experiments ascertains that the use of initial vertical beam polarization allows the cancellation of spin-dependent systematical errors imitating the EDM effect. While the use of this polarization meets certain difficulties, it should be considered as an alternative or supplementary possibility of fulfilling the EDM experiment.     

用于指导仲氢诱导核极化状态保存的己烯分子中五自旋的单重态制备和寿命研究

仲氢诱导核极化（PHIP）技术能极大地增强核磁共振（NMR）信号的灵敏度,已被应用于磁共振成像、原位化学反应监测等领域．除了不断提高不同分子极化后的灵敏度外,延长和保存高极化度状态对PHIP技术的应用也至关重要,其中将极化后的状态制备成核自旋单重态是目前被研究较多的一种方法．本文以能被PHIP技术极化的己烯分子为研究对象,通过设计优化控制脉冲,对分子中的一个五自旋体系进行操控,制备了多种核自旋单重态,结果表明：己烯分子的碳-碳双键上存在三种不同的核自旋单重态,它们的寿命均长于仲氢极化后产生的初始态的寿命,可以作为延缓极化度衰减的一种中间态;通过对比单重态的寿命与相应自旋的纵向弛豫时间发现,将极化后己烯的状态转化为纵向磁化可能也是一种保存极化度的有效方法．     

Nuclear moments as a probe of electronic structure in material, exotic nuclear structure and fundamental symmetry

We report our studies in various fields of Physics through nuclear moments utilizing the β-NMR technique, including material sciences, nuclear structures and fundamental symmetries. Especially, we focus on the recent progress in the studies on the electronic structure in Pt through Knight shifts of various impurities, lattice locations of impurities, electric field gradients, the analysis of nuclear spin in terms of its components, anomaly in the spin expectation value for ⁹C-⁹Li mirror pair, the G-parity conservation law, and the Ramsey resonance on UCN for future neutron EDM measurements.     

Higher order spin resonances in a 2.1-GeV/c polarized proton beam

Spin resonances can depolarize or spin flip a polarized beam. We studied 1st and higher order spin resonances with stored 2.1 GeV/c vertically polarized protons. The 1st order vertical (ν(y)) resonance caused almost full spin flip, while some higher order ν(y) resonances caused partial depolarization. The 1st order horizontal (ν(x)) resonance caused almost full depolarization, while some higher order ν(x) resonances again caused partial depolarization. Moreover, a 2nd order ν(x) resonance is about as strong as some 3rd order ν(x) resonances, while some 3rd order ν(y) resonances are much stronger than a 2nd order ν(y) resonance. One thought that ν(y) spin resonances are far stronger than ν(x), and that lower order resonances are stronger than higher order; the data do not support this.     

Search for electric dipole moment in 129Xe atom using a nuclear spin oscillator

We aim to measure the electric dipole moment (EDM) of a diamagnetic atom ¹²⁹Xe using an optical-detection nuclear spin maser technique. The relation of EDM in a diamagnetic atom to nuclear Schiff moment and fundamental sources generating it is discussed, and the present status for the development of our experimental setup is presented.     

Iron-57 Mössbauer spectroscopic study of fluorinated strontium orthoferrite

A nuclear spin maser of a new type, that employs a feedback scheme based on optical nuclear spin detection, has been fabricated. The spin maser is operated at a low static field of 30 mG by using the optical detection method. The frequency stability and precision of the spin maser have been improved by a highly stabilized current source for the static magnetic field. An experimental setup to search for an electric dipole moment (EDM) in ¹²⁹Xe atom is being developed.     

Manifestation of tensor magnetic polarizability of the deuteron in storage ring experiments

It was previously shown that the tensor magnetic polarizability of the deuteron causes the spin rotation with two frequencies and experiences beating for polarized deuteron beams in storage rings. We confirm an existence of this effect and derive general formulae describing deuteron spin dynamics. It is found that an initially tensor polarized deuteron beam can acquire a final horizontal vector polarization of order of 1%. This effect allows to measure the tensor magnetic polarizability of the deuteron in storage ring experiments.     

Present status of the 129Xe comagnetometer development for neutron EDM measurement

A ¹²⁹Xe comagnetometer designed for the measurement of neutron electric dipole moment (nEDM) as precisely as 1 × 10^?27e cm is presented. Highly nuclear spin polarized ¹²⁹Xe are introduced into an EDM cell where the ¹²⁹Xe spin precession is detected by means of the two-photon transition. The geometric phase effect (GPE) which generates the false nEDM was quantitatively discussed and the systematic error of nEDM from the GPE was estimated considering the buffer-gas suppression due to Xe atomic collisions. Research and development are in progress to construct the ¹²⁹Xe comagnetometer with a field sensitivity of 0.3 fT. At present, about 70 % nuclear spin polarized ¹²⁹Xe atoms have been obtained in a spin exchange opitial pumping cell, that are in the process of being transferred into the EDM cell via a cold trap.     

EPR study of the toxicological effects of gas-phase cigarette smoke and the protective effects of grape seed extract on the mitochondrial membrane

Electron paramagnetic resonance spin trapping and spin labeling techniques were used to study the effects of grape seed extract on the biophysical propertiers of the mitochondrial membrane exposed to gas-phase cigarette smoke. The spin trapping results indicated that grape seed extract can effectively scavenge free radicals in cigarette smoke and the lipid free radicals generated from the lipid peroxidation of mitochondrial membrane caused by gas-phase cigarette smoke. The spin labeling results showed that grape seed extract can protect the mitochondrial membrane from the toxicological damage caused by gas-phase cigarette smoke.     

Calculation of properties of the ozone molecule by the multiconfigurational self-consistent field method

For the ground state of the ozone molecule, by using the multiconfigurational self-consistent field method, we calculated the electric and magnetic properties — quadrupole moment, polarizability, tensor of magnetic susceptibility, nuclear quadrupole interaction constant, and the rotational g-factor. Qualitative agreement between the calculated parameters and experimental values was obtained. The tensors of chemical shielding in the spectrum of the nuclear magnetic resonance for the ¹⁷O isotopes have also been predicted (without allowance for the contribution made by the spin of the electrons). __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 713–716, November–December, 2005.     

杂质散射引起的亚铁磁体的共振线宽

本文得到了具有二个等价次点阵的椭球亚铁磁体的二支自旋波频谱,它们的频率对波矢的依赖关系与椭球铁磁体的相类似。基于此频谱和交换作用涨落引起的自旋波散射机制,计算了一致共振和交换共振的线宽。对一致共振,用等效铁磁模型得到的结论仍然成立:非磁性杂质离子和自旋等于同一次点阵上基质离子自旋的杂质离子,对一致共振线宽没有贡献。但这二类杂质离子对交换共振线宽有贡献。用我们的简化亚铁磁模型对各种铁氧体算得的一致共振线宽差别很大。对许多尖晶石型铁氧体,交换作用涨落可能是引起一致共振线宽的主要机制。对于铁氧体,由此机制引起的交换共振线宽其数量级为几十奥。     

含stubs量子波导系统的电子自旋极化输运性质

理论上研究了含stubs的Rashba自旋轨道耦合（spin-orbit coupling, SOC）量子波导系统的自旋极化输运性质. 利用晶格格林函数方法,发现由于stubs和SOC产生的势阱使系统中出现束缚态,这些束缚态与传播态之间相互干涉导致电导中出现Fano共振结构,同时在对应的自旋极化率中也出现Fano共振或反共振结构. 此外,由于系统结构的突变使电子被反向散射和量子干涉效应,电导中出现一系列的共振峰. 但是,当系统加上外磁场后,所有这些效应都被抑制, 系统重新出现量子化电导, 同时自旋电导也出 关键词： 量子波导 自旋极化输运 自旋轨道耦合     

Effects of averaging of spin packets of interacting resonances in Gd<Superscript>3+</Superscript> EPR spectra of scheelites

The EPR spectra of Gd³⁺ tetragonal centers in crystals with a scheelite structure are analyzed. It is found that the EPR spectra exhibit additional signals in the vicinity of coincidence of the resonance lines attributed to Gd³⁺ EPR transitions. It is shown that these signals are caused by averaging (due to relaxation spin-lattice transitions between the resonance doublets) of the internal part of the quasi-symmetric system of spin packets corresponding to the inhomogeneously broadened initial EPR lines. The quasi-symmetric arrangement of the spin packets is associated with the mosaic structure of the studied crystals.     

An investigation of the properties of single-particle states in the second minimum of 237Pu

In connection with the recent measurement of the magnetic moments of the fission isomeric states in ²³⁷Pu, we investigate the following subjects: (i) The spin alignment of the lowest-lying states in a potential minimum which are populated by (α, 2nγ) reactions, and the fragment angular distributions in fission from isomeric states. (ii) The single-particle level scheme in a very deformed Woods-Saxon potential. (iii) The spin polarizability as a function of the quadrupole deformation.     

Noncovalent interactions involving aromatic rings: correlation analysis via substituent constants

The elucidation of the mechanism of the substituent influence on the properties P (the interaction energies E, interring distances l, and free energies ΔG of interaction) of weak complexes involving aromatic rings is of importance not only theoretically but also from a practical standpoint. This mechanism is little understood. In this work, the literature data on the substituent influence on P properties for 42 series of complexes have been analyzed, using correlation analysis. Generally, the inductive, resonance, polarizability, and steric effects are in operation. The presence or absence of certain effects and the relation between their contributions are determined by the type of series. The polarizability effect (an electrostatic ion‐dipole interaction) is caused by an excess charge appearing on the ring substituted fragment of complexes as a result of the complexation. This effect is observed in all series; its contribution ranges up to approximately 50%.