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1.
The QCD sum rules for spin-dependent nucleon-nucleon (N N) and hyperon-nucleon (Y N) interactions are formulated and their physical implications are clarified. A dispersion integral around the nucleon threshold can be identified as a measure of interaction strength. Calculating the operator product expansion (OPE) of the correlation function, we have found that the spin-dependent operators are related to the axial and tensor charges. The obtained sum rules relate the interaction strengths to the nucleon matrix elements of the quark-gluon operators. The spin-dependent parts are smaller than the spin-independent parts in the N N and the Y N channels. The spin-independent N N interaction strength is greater than the spin-independent Y N interaction strengths. The results are consistent with the empirical result in the N N channel. 相似文献
2.
Spinor F=1 Bose–Einstein condensates loaded in two types of radially-periodic potentials with spin–orbit coupling
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《中国物理 B》2021,30(10):106701-106701
We consider two-dimensional spinor F = 1 Bose–Einstein condensates in two types of radially-periodic potentials with spin–orbit coupling, i.e., spin-independent and spin-dependent radially-periodic potentials. For the Bose–Einstein condensates in a spin-independent radially-periodic potential, the density of each component exhibits the periodic density modulation along the azimuthal direction, which realizes the necklacelike state in the ferromagnetic Bose–Einstein condensates. As the spin-exchange interaction increases, the necklacelike state gradually transition to the plane wave phase for the antiferromagnetic Bose–Einstein condensates with larger spin–orbit coupling. The competition of the spin-dependent radially-periodic potential, spin–orbit coupling, and spin-exchange interaction gives rise to the exotic ground-state phases when the Bose–Einstein condensates in a spin-dependent radially-periodic potential. 相似文献
3.
We include the spin-orbit force in the analysis of inelastic proton-nucleus scattering. In the limit of zero-range nuclear forces, very simple results are obtained. To lowest order in the elementary spin-orbit amplitude, the spin-dependent nuclear amplitudes are proportional to the momentum transfer times the spin-independent nuclear amplitudes. Consequently, in the spin-independent cross section the region of the diffractive minima is not significantly affected by the elementary spinorbit amplitudes, whereas the subsidiary maxima are somewhat enhanced. 相似文献
4.
Nuclear effects due to the presence of spin-1 isosinglet 6-quark clusters in the deuteron on the extraction of both spin-independent
and spin-dependent neutron structure functions are investigated. The x-dependences of the 6-quark cluster structure functions are estimated by using a perturbative QCD (pQCD) dimensional counting
rules. Within this framework, the ratio of the deuteron structure function to the free nucleon structure function can be well
described. We find that the nuclear effect on the extracted spin-dependent neutron structure function is very different from
that on the spin-independent neutron structure function. The effect enhances the Bjorken sum by about 10%, whereas it decreases
the Gottfried sum by about 7%. The formalism for calculating nuclear effects is further used to evaluate the spin-dependent
structure function of the He nucleus and a good self-consistent check is obtained.
Received: 1 December 2000 / Revised version: 15 February 2001 / Published online: 25 April 2001 相似文献
5.
Dark matter (DM) annihilations in the Sun to neutrino–antineutrino pairs are known to have potentially observable signatures in neutrino telescopes such as IceCube and KM3. We propose a model independent analysis in which the monochomatic neutrino signal from dark matter (DM) annihilations in the Sun is related to the direct detection spin-independent and spin-dependent cross sections rather than assuming cross sections from a particular model. We propagate the neutrinos from the center of the Sun to the Earth taking into account matter effects on neutrino oscillations. For DM capture in the Sun via a large spin-dependent DM capture cross section the discovery prospects of the IceCube experiment are found to be promising. 相似文献
6.
Self-consistent Hartree-Fock and RPA calculations with the Skyrme-type interaction SGII are used for a systematic investigation of the 1+ and the triplet 0?, 1?, 2? states in 40Ca and 208Pb. Response functions to spin-dependent multipole operators are calculated and the particle-hole structure of the spin-dependent collective states is studied. Collective spin-dependent 0? and 1? states above the giant dipole resonance as well as a collective spin-independent 2? state (twist mode) are identified. Transition spin and current densities are calculated for the collective excitations and found to be useful for the study of these excitation modes. 相似文献
7.
Lee HS Bhang HC Choi JH Dao H Hahn IS Hwang MJ Jung SW Kang WG Kim DW Kim HJ Kim SC Kim SK Kim YD Kwak JW Kwon YJ Lee J Lee JH Lee JI Lee MJ Lee SJ Li J Li X Li YJ Myung SS Ryu S So JH Yue Q Zhu JJ;KIMS Collaboration 《Physical review letters》2007,99(9):091301
The Korea Invisible Mass Search (KIMS) experiment presents new limits on the weakly interacting massive particle (WIMP)-nucleon cross section using data from an exposure of 3409 kg.d taken with low-background CsI(Tl) crystals at the Yangyang Underground Laboratory. The most stringent limit on the spin-dependent interaction for a pure proton case is obtained. The DAMA signal region for both spin-independent and spin-dependent interactions for the WIMP masses greater than 20 GeV/c2 is excluded by the single experiment with crystal scintillators. 相似文献
8.
A. V. Afanasev I. Akushevich N. P. Merenkov 《Journal of Experimental and Theoretical Physics》2004,98(3):403-416
The electron structure function method is applied to calculate model-independent QED radiative corrections to the asymmetry of electron-proton scattering. Representations for both spin-independent and spin-dependent parts of the cross section are derived. Master formulas include the leading corrections in all orders and the main contribution of the second order and provide accuracy of the QED corrections at the level of one per mill. Numerical calculations illustrate our analytic results for both elastic and deep inelastic events. 相似文献
9.
Antony Lewis Chris Doran Anthony Lasenby 《International Journal of Theoretical Physics》2001,40(1):363-376
Using the spacetime algebra formulation of the Dirac equation, we demonstrate how to perform cross-section calculations following a method suggested by Hestenes (1982). Instead of an S-matrix, we use an operator that rotates the initial states into the scattered states. By allowing the scattering operator to become a function of the initial spin, we can neatly handle spin-dependent calculations. When the operator is independent of spin, we can provide manifestly spin-independent results. We use neither spin basis nor spin sums, instead handling the spin orientation directly. As examples, we perform spin-dependent calculations in Coulomb scattering to second order, and briefly consider more complicated calculations in QED. 相似文献
10.
11.
A. V. Afanasev I. Akushevich G. I. Gakh N. P. Merenkov 《Journal of Experimental and Theoretical Physics》2001,93(3):449-461
We completely analyze the model-independent leading radiative corrections to the cross section and polarization observables in the semi-inclusive deep-inelastic electron-nucleus scattering with the detection of a proton and the scattered electron in coincidence. The calculations are based on representing the spin-independent and spin-dependent parts of the cross section in terms of the electron structure functions similarly to the Drell-Yan-like representation in electrodynamics. As the applications, we consider the polarization transfer effect from a longitudinally polarized electron beam to the detected proton and the scattering by a polarized target. 相似文献
12.
《Journal of magnetism and magnetic materials》2002,247(2):178-186
The contribution to the magnetoresistance (MR) was calculated for a single magnetic domain wall present in a small 2D impure ferromagnetic wire. On assuming low-temperatures and spin-independent impurity scattering the mechanism responsible for a positive contribution to MR is quantum interference. It is found that the contribution increases with impurity concentration and reduces with the width of the wall. The influence on the MR of a homogeneous electric field is proved to be spin-dependent. 相似文献
13.
《中国物理 B》2015,(7)
The effect of interfacial coupling on rectification in an organic co-oligomer spin diode is investigated theoretically by considering spin-independent and spin-resolved couplings respectively. In the case of spin-independent coupling, an optimal interfacial coupling strength with a significant enhanced rectification ratio is found, whose value depends on the structural asymmetry of the molecule. In the case of spin-resolved coupling, we found that only the variation of the interfacial coupling with specific spin is effective to modulate the rectification, which is due to the spin-filtering property of the central asymmetric magnetic molecule. A transition of the spin-current rectification between parallel spin-current rectification and antiparallel spin-current rectification may be observed with the variation of the spin-resolved interfacial coupling. The interfacial effect on rectification is further analyzed from the spin-dependent transmission spectrum at different biases. 相似文献
14.
G. H. Bordbar M. J. Karimi A. Poostforush 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(1):85-94
We have used the lowest order constrained variational (LOCV) method to calculate some thermodynamic properties of the polarized liquid 3He at finite temperature with the spin-dependent correlation function. For each value of the temperature and density we have shown that the main contribution to the potential energy comes from the spin-triplet state. For the polarized liquid 3He, we have seen that the differences between the thermodynamic properties of the spin-dependent and the spin-independent cases decrease by increasing both polarization and temperature. For all relevant temperatures and densities, our results do not show any ferromagnetic phase transition. 相似文献
15.
I. Antoniadis S. Baessler M. Büchner V.V. Fedorov S. Hoedl A. Lambrecht V.V. Nesvizhevsky G. Pignol K.V. Protasov S. Reynaud Yu. Sobolev 《Comptes Rendus Physique》2011,12(8):755-778
We consider theoretical motivations to search for extra short-range fundamental forces as well as experiments constraining their parameters. The forces could be of two types: 1) spin-independent forces; 2) spin-dependent axion-like forces. Different experimental techniques are sensitive in respective ranges of characteristic distances. The techniques include measurements of gravity at short distances, searches for extra interactions on top of the Casimir force, precision atomic and neutron experiments. We focus on neutron constraints, thus the range of characteristic distances considered here corresponds to the range accessible for neutron experiments. 相似文献
16.
杨丽桃 李浩斌 岳骞 康克军 程建平 李元景 王子敬 M.Agartioglu 安海鹏 常建平 陈景瀚 陈云华 邓智 杜强 宫辉 何力 胡津纬 胡庆东 黄瀚雄 贾历平 江灏 李红 李荐民 李金 李霞 李学潜 李玉兰 林枫凯 林兴德 刘书魁 刘仲智 马豪 马菁露 潘辉 任杰 阮锡超 B.Sevda Vivek Sharma 申满斌 Lakhwinder Singh Manoj Kumar Singh 唐昌建 唐维优 田阳 王继敏 王力 王青 王轶 吴世勇 吴玉成 幸浩洋 徐音 薛涛 杨松伟 易难 喻纯旭 于海军 岳剑峰 曾雄辉 曾鸣 曾志 张云华 赵明刚 赵伟 周济芳 周祖英 朱敬军 朱忠华 《中国物理C(英文版)》2018,(2)
We report results of a search for light weakly interacting massive particle(WIMP) dark matter from the CDEX-1 experiment at the China Jinping Underground Laboratory(CJPL). Constraints on WIMP-nucleon spin-independent(SI) and spin-dependent(SD) couplings are derived with a physics threshold of 160 eVee, from an exposure of 737.1 kg-days. The SI and SD limits extend the lower reach of light WIMPs to 2 GeV and improve over our earlier bounds at WIMP mass less than 6 GeV. 相似文献
17.
J. Ellis J.L. Feng A. Ferstl K.T. Matchev K.A. Olive 《The European Physical Journal C - Particles and Fields》2002,24(2):311-322
A new set of supersymmetric benchmark scenarios has recently been proposed in the context of the constrained MSSM (CMSSM)
with universal soft supersymmetry-breaking masses, taking into account the constraints from LEP, and . These points have previously been used to discuss the physics reaches of different accelerators. In this paper, we discuss
the prospects for discovering supersymmetric dark matter in these scenarios. We consider direct detection through spin-independent
and spin-dependent nuclear scattering, as well as indirect detection through relic annihilations to neutrinos, photons, and
positrons. We find that several of the benchmark scenarios offer good prospects for direct detection via spin-independent
nuclear scattering and indirect detection via muons produced by neutrinos from relic annihilations inside the Sun, and some
models offer good prospects for detecting photons from relic annihilations in the galactic centre.
Received: 17 October 2001 / Revised version: 14 January 2002 / Published online: 12 April 2002 相似文献
18.
V.A. Beylin V.I. Kuksa R.S. Pasechnik G.M. Vereshkov 《The European Physical Journal C - Particles and Fields》2008,56(3):395-405
We analyze a connection between the neutralino mass sign, parity and structure of the neutralino–boson interaction. Correct
calculation of spin-dependent and spin-independent contributions to neutralino–nuclear scattering should consider this connection.
A convenient diagonalization procedure, based on the exponential parametrization of unitary matrix, is suggested.
PACS 11.30.Pb; 14.80.Ly; 12.60.Jv 相似文献
19.
The energy band structure of spin-1 condensates with repulsive spin-independent and either ferromagnetic or antiferromagnetic spin-dependent interactions in one-dimensional (1D) periodic optical lattices is discussed. Within the two-mode approximation, Bloch bands of spin-1 condensates are presented. The results show that the Bloch bands exhibit a complex structure as the atom density of m F=0 hyperfine state increases: bands splitting, reversion, intersection and loop structure are excited subsequently. The complex band structure should be related to the tunneling and spin-mixing dynamics. 相似文献
20.