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1.
本文讨论了一个SU(2) Higgs场与费米子场的标量耦合模型. 主要结果是: (1) 把Julia-Zee双子处理为外势, 得到了费米子径向波函数所满足的联立方程程组; (2) 求出了无穷远处和零点附近的渐近解; (3) 定性地讨论了费米子束缚态存在的必要条件. 发现, 对于磁单极情形, 当h→0时, 必不存在费米子束缚态. 对于双子情形, 在h→0的情况下, 费米子束缚态可能存在.  相似文献   

2.
李新洲  汪克林  张鉴祖 《物理学报》1985,34(11):1488-1493
在自发破缺的具有Higgs三重态的SU(2)规范理论中,讨论了同位旋1/2的费密子的质量对费密子-磁单极束缚态的影响。结果表明,当费密子与Higgs场之间的直接耦合趋于零,但狄拉克质量保持固定时,费密子-磁单极束缚态的必要条件必不被满足。这个结果意味着对于SU(2)模型由于狄拉克质量效应,Rubakov效应不存在。 关键词:  相似文献   

3.
张鉴祖  祁永昌 《物理学报》1990,39(5):699-706
本文获得荷电费密子与阿贝耳双子束缚系统在双子电荷Zddc和系统总角动量j≥/q/+1/2条件下的束缚态波函数和能谱。计算了该系统在外电磁场中的跃迁矩阵元和确定了相应的选择定则。发现存在与通常类氢原子不同的、破坏宇称守恒的△j=0的电偶极跃迁。 关键词:  相似文献   

4.
采用中子n-反中子n与中性介子π0强相互作用的Lorentz不变耦合模型,对n-n重正化链图传播子作了有关物理分析及其严格解析计算,获得精确理论计算结果. 进而将此结果用于n+n→2π0反应的物理过程分析及其截面的计算研究中,并精确计算出n-n重正化链图传播下n+n→2π0反应微分截面. 还将此计算结果与n-n树图和重正化单圈链图传播下n+n→2π0反应微分截面作了对比分析,获得了有关辐射修正的重要信息. 此结果对于深 关键词: Lorentz不变耦合模型 重正化链图传播子 微分截面 辐射修正  相似文献   

5.
周玉魁  云国宏 《物理学报》1989,38(4):648-652
本文用量子反散射方法讨论了最一般的超矩阵量子非线性Schr?dinger模型的本征态。特别是构造了玻色和费密粒子混合的N粒子束缚态。N粒子的散射态和束缚态的能量分别为∑j=1Nλj2和Np2-(c2/12)N(N2-1)。 关键词:  相似文献   

6.
本文给出了Ti-Pd系合金样品的低温比热的测量结果,得出样品Ti0.92Pd0.08及Ti0.8Pd0.2的电子比热系数r分别为5.89mJ/mol·K2和4.78mJ/mol·K2,显然比纯Ti的r值3.32mJ/mol·K2高得多。因此,它们的费密面的电子态密度也比纯Ti的高,这正是Ti-Pd系合金的超导转变温度Tc比纯Ti的有较大幅度提高的原因。 关键词:  相似文献   

7.
幂函数叠加势的径向薛定谔方程的解析解   总被引:3,自引:0,他引:3       下载免费PDF全文
胡先权  罗光  马燕  崔立鹏 《物理学报》2009,58(4):2168-2173
研究多种正幂势函数与逆幂势函数紧密耦合条件下薛定谔径向方程解析解的求解方法.对势函数为Vr)=α1r8α2r3+α3r2+β3r-1β2r-3β1r-4的径向薛定谔方程存在解析解的条件以及精确的解析解进行了研究. 根据量子系统波函数必须满足单值、有界和连续的标准条件,首先求出径向坐标r→∞以及r→0时的渐近解,然后采用非正则奇点邻域附近的波函数级数解法与求得的渐近解相结合,通过幂级数系数比较法得到径向薛定谔方程在势函数系数紧密耦合条件下的一系列定态波函数解析解以及相应的能级结构,并作适当讨论与结论. 关键词: 级数解法 幂势函数 径向波函数 渐近解  相似文献   

8.
章世伟  苏汝铿 《物理学报》1982,31(3):311-317
本文讨论在Kerr度规中带质量和无质量Bose子的束缚态,结果指出:1)无质量Bose子不能形成Kerr黑洞束缚态,在极端黑洞情形和角量子数l很大的条件下,这与deFelic的结论相符,但我们将他的结论推广到任意l及非极端Kerr黑洞的情形。2)对于有质量Bose子,若满足束缚态条件,则可能和极端Kerr黑洞组成束缚态。本文给出了束缚态的能量模式,波函数和束缚态条件。 关键词:  相似文献   

9.
Schwarzschild黑洞的Dirac粒子准束缚态   总被引:1,自引:0,他引:1       下载免费PDF全文
章世伟 《物理学报》1983,32(6):823-828
本文将Schwarzschild度规中的二分量Dirac方程(Brill-Wheeler方程)化为一个单分量的二阶方程,考查了方程的有效势,找出了自旋轨道耦合项。视界附近是一个势垒,当K2>3η2,势垒外侧出现势阱。Dirac粒子将在势阱中某些能级上共振,并穿越势垒被视界吸收。借WKB方法求得准束缚态的能谱,并计算了大|K|情形下的寿命。同样的处理方法还推广至Reissner-Nordstrom度规。 关键词:  相似文献   

10.
本文构建了由生物膜光合产氢反应器和单室无膜空气阴极微生物燃料电池组成的耦合系统,以葡萄糖溶液为底物(模拟废水)对上述系统的能量回收和污水处理持性进行了考察。实验发现,由于耦合系统各组成部分最佳性能时所要求的底物流量不同,使系统的能量回收与废水处理效率随运行工况的变化而体现出不同的特性。当底物流量为10 mL·h-1时,耦合系统能量回收效率最大,为11.2%;而当底物流量为40 mL·h-1时,耦合系统的COD去除效率和功率密度达到最佳,分别为76.4%和5.97×105 J·m-3·h-1。  相似文献   

11.
N. Sakai 《Nuclear Physics B》1984,238(2):317-332
Proton decay is studied in the supergravity model with “the hidden sector” as the source of supersymmetry breaking. Each dimension-five operator is found to accompany ΔB ≠ 0 four-scalar interactions. The Higgs fermion exchange for loop diagrams at low energies can be as important as the gauge fermion exchange, if the associated Yukawa coupling is significant as suggested by the radiatively induced SU(2) × U(1) breaking mechanism. The experimental bound for p → K0μ+ gives the lower bound of the order of 1016 GeV for the mass of the baryon-number violating Higgs particle.  相似文献   

12.
祁永昌 《物理学报》1993,42(4):544-550
ZZd?137的荷电费密子-狄喇克双子束缚态的能谱,按照它们不同的K=n+[μ]整数可以分为不同的线系,每个能级具有(2j+1)度简并。在均匀磁场中,由于塞曼效应,简并将完全消除。 关键词:  相似文献   

13.
Lower limits on the half-life of theββ(2v+0v) decay of76Ge to the excited states in76Se have been obtained using the results of low-background measurements with a HPGe detector surrounded by passive germanium shielding: T1/2(0+ → 2 1 + ) >1.1 · 1021 y, T1/2(0+ → 0 1 + ) > 1.7 · 1021 y, T1/2(0+ → 22/+) > 1.4 ·1021 y.  相似文献   

14.
Rotational analyses of the two 0-0 bands of theB 2ΣX 2Πreg system of SbO were carried out for the first time from spectrograms taken in the second order of a 21 ft. concave grating spectrograph having a dispersion of 1·25 Å/mm. The rotational constants of the ν=0 vibrational levels of the upper and lower states, and of the coupling constant A0 of the lower2Πreg state were deduced. These values are summarised below. v00=25 334·93 cm?1 B′0=0·3190 cm?1 B″0=0·3490 cm?1 A 0=2276 cm?1 r′0=1·933 Å r″0=1·848 Å.  相似文献   

15.
苏成悦 《物理学报》2001,50(11):2089-2091
利用Ernst方法,在Harrison变换为线性变换的条件下,得到Kasuya荷电荷磁的外部引力场解,解中所含常量B0表示一均匀弱磁场,该解不要求q=-2B0J.当r趋于∞时,度规接近Melvin’s磁宇宙的渐进行为.该度规是非渐近平直的,在均匀外磁场下这是合理的结果. 关键词: Ernst方法 Kasuya双荷 磁场 引力场  相似文献   

16.
Tae-Kyu Ha 《Molecular physics》2013,111(6):1829-1846
Configuration interaction (CI) studies of ground, n→ π* and π→ π* electronically excited states are reported for s-tetrazine. The first n→ π* singlet excited state (1 B 3u ), which is responsible for the purple-red colour of the molecule, is calculated at 2·80 eV, compared to the experimental transition energy of 2·22–2·70 eV. The singlet-triplet split of the first n→ π* states (1 B 3u and 3 B 3u states) is calculated to be 0·76 eV.

The interaction of nitrogen lone pair orbitals (n-orbitals) is studied in terms of the ordering of the n π* excited states and found that the SCF orbital ordering is qualitatively in accord with the ordering of the n π* excited states in the CI level.

The first π→ π* excited state (1 B 2u ) is calculated at 5·99 eV, slightly above the observed range of absorption. Numerous other high-lying singlet states as well as the triplet states have been calculated and they are used to verify several proposals relating to the excited state dynamics in the photo-physical studies of s-tetrazine.  相似文献   

17.
The energy spectrum of the bound states of the nucleon-monopole system is determined, the monopole harmonics Yq,l,m are related to Wigner's functions D m,m (L) of the rotation matrix, and the scattering wave functions of the proton in the dyon source field are calculated.  相似文献   

18.
The 19F N.M.R. spectra of CF2BrCClBr2 in CS2 from 20°c to -80°c are reported. Computer-fitting of the experimental spectra using the density matrix formalism of Alexander yields the chemical exchange correlation times and produces a computed internal rotation barrier for trans →gauche of 39·7 ± 0·5 kJ mol-1 (9·5±0·1 kcal/mole). Results of double resonance studies on the -80°c spectrum upon irradiation of the various peaks with a strong r.f. field are presented. The density matrix equations in the presence of chemical exchange and several relaxation mechanisms were solved to obtain theoretical changes in peak intensities on irradiation. The indirect spin saturation data and their relation to the rate of internal rotation and the relaxation mechanism are discussed. Random field relaxation is shown to be the important relaxation mechanism in the system. The strong irradiation of one component of a strongly coupled spin multiplet with intramolecular exchange causes indirect saturation of the transitions connecting energy levels that have the same m I values as the one being irradiated whereas the intensities of other transitions are only slightly affected. It appears therefore to be an important complement to the spin-tickling technique in determining energy level diagrams and relative signs of coupling constants.  相似文献   

19.
Relativistic effective core potential calculations have been employed in the framework of a spin–orbit configuration interaction to compute the lowest-lying electronic states of the CaBr2+ and CaI2+ dications, and the results are compared with the data for the isovalent CaCl2+ system studied earlier. The ground X2Π state in all three dications arises from a strong polarization of X(2P°)(X= Cl, Br or I) by the Ca2+(1S) ion and is bound by 0·96–1·55eV with respect to the corresponding diabatic dissociation limits. It is split by the spinorbit interaction into the X1 2Π3/2 and X2 2Π1/2 components, with the energy splittings calculated to be 647 cm-1(CaCl2+), 2115 cm-1(CaBr2+) and 3544 cm-1(CaI2+). The X1 and X2 states are found to be thermodynamically stable in CaCl2+ and CaBr2+, while in CaI2+ the lowest dissociation limit, Ca++(2S)+ I+ 3P2), lies 1700 and 5200 cm-1 lower than the X1 and X2 minima respectively. The X1 and X2 states in CaI2+ are extremely long-lived, however, owing to the high and very broad potential barriers to dissociation. The first electronic excited state, A2σ+, is also bound in all the above systems, although it is pre-dissociated in CaBr2+and CaI2+ at large internuclear distances. All other low-lying electronic states of CaX2+ are repulsive. Electric-dipole moments are calculated for the A→ X1, X2 transitions. The corresponding radiative lifetimes are found to be very long in CaCl2+ : τ(A→X1) = 19·3 ms and τ(A→X2) = 9·9 ms (the values are given for ν' = 0), and become very significantly shorter for CaBr2+ and CaI2+ because of the stronger spin-orbit interaction in the heavier systems. This effect is especially noticeable for the A →X2 transitions, for which the values are computed to be 364 μs in CaBr2+ and 50·3 μs in CaI2+. The theoretical data obtained should aid in the future spectroscopic detection of these species. To data no experiment of this type has been successfully carried out for any of the thermodynamically stable diatomic dications.  相似文献   

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