共查询到20条相似文献,搜索用时 15 毫秒
1.
O. Félix-Beltrán M. Gómez-Bock E. Hernández A. Mondragón M. Mondragón 《International Journal of Theoretical Physics》2011,50(7):2291-2303
We study the singularity of the surface that represents the masses of the isolated doublet of heavy, neutral Higgs bosons,
H
2–H
3, in a toy model based on the MSSM with CP violation, in parameter space. These two heavy, neutral Higgs bosons are coherent
and, for large values of the masses, nearly degenerate. In this scenario, mixing between the mass eigenstates of the H
2–H
3 system could be very large and exact degeneracy is possible. As function of the Lagrangian parameters, the physical mass
of the doublet has an algebraic branch point of rank one at the exceptional point where the two masses are equal. The real
and imaginary parts of the masses in the doublet have branch cuts that start at the same branch point but extend in opposite
directions in parameter space. Associated with this branch point, the propagator of the mixing doublet of neutral heavy Higgs
bosons has a double pole in the complex s-plane of the energy squared. We computed the mass surface of the isolated doublet of H
2–H
3 bosons as function of the Lagrangian parameters in the neighbourhood of the exceptional point in a toy model of the system
H
2–H
3. We also computed the trajectories of the poles of the transition matrix for values of the Lagrangian parameters close to
the exceptional point and explained the characteristic change of identity seen in these trajectories in the s-plane as a manifestation of the topology of the two-sheeted mass surfaces in the space of Lagrangian parameters. 相似文献
2.
Najate Bensari-zizi Claude Alamichel 《International Journal of Infrared and Millimeter Waves》1989,10(1):137-151
About 2500 lines of CH3
35Cl have been assigned. The strong xy Coriolis resonance between thev
2 andv
5 modes is quite visible between thev
4+v
4
±1
perpendicular band, centered around 4383 cm–1, and thev
4
±1
+v
5
±1
perpendicular component, centered around 4475 cm–1, with a crossing of upper energy levels allowing the observation of lines which are normally forbidden. Although not yet observed with certainty, because of the great density of lines of the spectrum, thev
4
1
+v
5
±1
parallel component is nevertheless detectable by its effects onv
2+v
4
±1
which is linked by Coriolis resonance to both components ofv
4+v
5. Moreover the spectrum is much complicated by many other resonances with weak bands which occur at level crossings: it is the case ofv
2+3v
6
±1
, connected tov
2+v
4
±1
by the well known Darling Dennison resonance which couplesv
4
±1
and 3v
6
±1
, and also ofv
5
±1
+3v
6
±1
connected tov
4
±1
+v
5
±1
by the same resonance; but this last case is complicated by an anharmonic resonance betweenv
5
±1
+3v
6
±1
and 2v
3+3v
6
1
. Two more perturbations occur on the K=–1 side ofv
2+v
4: a weak Coriolis resonance gives rise to one subband ofv
1+v
2 at a level crossing withv
2+v
4, and thev
1+v
5 band (linked of course tov
1+v
2 by the Coriolis resonance between thev
2 andv
5 modes) is quite visible and perturbs several subbands ofv
2+v
4 of high values of K through an anharmonic resonance. Moreover, the complex (3v
5
±1
,v+2v
5
0
, 2v
2+v
5
±1
, 3v
2,v
2+2v
5
±2
, 3v
5
±3
) system of Coriolis-connected bands is linked to the bands studied in the present work by two Fermi resonances: one betweenv
2+2v
5
0
andv
1+v
2, and the other one betweenv
1+v
5 and 3v
5
±1
, whose several subbands have been observed on the low part of the spectrum. The values of all the band centres and of the different coupling constants have been estimated, but all these interactions make the line assignments and the interpretation of the spectrum very difficult. 相似文献
3.
4.
5.
6.
On the basis of the decay couplings f
0 → ππ, K
, ηη, ηη′ found earlier in the study of analytical (IJ
PC
=00++) amplitude in the mass range 450–1900 MeV, we analyze the quark-gluonium content of the resonances f
0(980), f
0(1300), f
0(1500), and f
0(1750) and the broad state f
0(1420
−70
+150
). The K-matrix technique used in the analysis makes it possible to evaluate the quark-gluonium content both for the states with switched-off
decay channels (bare states, f
0
bare
) and for the real resonances. We observe a significant change in the quark-gluonium composition in the evolution from bare
states to real resonances, which is due to the mixing of states in the transitions f
0(m
1) → real mesons → f
0 (m
2) responsible for the decay processes as well. For f
0(980), the analysis confirmed the dominance of q
component, thus proving the n
/s
composition found in the study of the radiative decays. For the mesons f
0(1300), f
0(1500), and f
0(1750), the hadronic decays do not allow one to determine uniquely the n
, s
, and gluonium components, providing relative percentage only. The analysis shows that the broad state f
0(1420
−70
+150
) can mix with the flavor singlet q
component only, which is consistent with gluonium origin of the broad resonance.
From Yadernaya Fizika, Vol. 66, No. 4, 2003, pp. 772–785.
Original English Text Copyright ? 2003 by Anisovich, Nikonov, Sarantsev.
This article was submitted by the authors in English. 相似文献
7.
V. V. Vien 《中国物理C(英文版)》2021,45(12):123103-123103-14
We construct a non-renormalizable gauge \begin{document}$ B-L $\end{document} ![]()
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model based on \begin{document}$ Q_4\times Z_4\times Z_2 $\end{document} ![]()
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symmetry that successfully explains the cobimaximal lepton mixing scheme. Small active neutrino masses and both neutrino mass hierarchies are produced via the type-I seesaw mechanism at the tree-level. The model is predictive; hence, it reproduces the cobimaximal lepton mixing scheme, and the reactor neutrino mixing angle \begin{document}$ \theta_{13} $\end{document} ![]()
![]()
and the solar neutrino mixing angle \begin{document}$ \theta_{12} $\end{document} ![]()
![]()
can obtain best-fit values from recent experimental data. Our model also predicts the effective neutrino mass parameters of \begin{document}$ m_{\beta }\in (8.80, 9.05)\, \mathrm{meV} $\end{document} ![]()
![]()
and \begin{document}$ \langle m_{ee}\rangle \in (3.65, 3.95)\, \mathrm{meV} $\end{document} ![]()
![]()
for normal ordering (NO) and \begin{document}$ m_{\beta }\in (49.16, 49.21)\, \mathrm{meV} $\end{document} ![]()
![]()
and \begin{document}$ \langle m_{ee}\rangle \in (48.59, 48.67)\, \mathrm{meV} $\end{document} ![]()
![]()
for inverted ordering (IO), which are highly consistent with recent experimental constraints. 相似文献
8.
U. V. Valiev J. B. Gruber I. R. Gapdulkhakov N. I. Juraeva A. K. Mukhammadiev Sh. A. Rakhimov I. S. édel’man 《Optics and Spectroscopy》2009,106(6):851-857
The spectra of luminescence and magnetic circular polarization of luminescence in the 1
D
2 → 3
F
4 emission band in thulium:yttrium-aluminum garnet Tm3+:YAG (Tm3+:Y3Al5O12) have been investigated at temperatures T = 78 and 293 K, respectively. Based on the analysis of the magnetooptical and optical spectra, the optical transitions between
the Stark sublevels of the 3
F
4 and 1
D
2 multiplets in Tm3+:YAG were identified. It is shown that the symmetry and energies of the Stark sublevels of the 3
F
4, 1
D
2, and 3
H
6 multiplets, found experimentally from magnetic and magnetooptical studies, confirm the results of theoretical calculations
of the energy spectrum of the rare earth Tm3+ ion in YAG.
Original Russian Text ? U.V. Valiev, J.B. Gruber, I.R. Gapdulkhakov, N.I. Juraeva, A.K. Mukhammadiev, Sh.A. Rakhimov, I.S.
édel’man, 2009, published in Optika i Spektroskopiya, 2009, Vol. 106, No. 6, pp. 937–944. 相似文献
9.
Absorption spectra of β -carotene in 31 solvents
are measured in ambient conditions. Solvent effects on the 0--0 band
energy, the bandwidth, and the transition moment of the S0 →
S2 transition are analysed. The discrepancies between published
results of the solvent effects on the 0--0 band energy are
explained by taking into account microscopic solute-solvent
interactions. The contributions of polarity and polarizability of
solvents to 0--0 band energy and bandwidth are quantitatively
distinguished. The 0--0 transition energy of the S2 state at the gas
phase is predicted to locate between 23000 and 23600~cm-1. 相似文献
10.
The 31Πg state of Na2 is experimentally investigated by using high resolution cw optical-optical double resonance spectroscopy. A single line Ar+ laser (total of 9 lines) is used to pump the sodium dimers from thermally populated ground state to the intermediate B1Πu state. Then a single mode Ti:sapphire laser is used to probe the 31Πg state. Violet fluorescence from highly Rydberg excited states (mainly 23Πg or 33Πg states which are transferred from 31Πg state via collisions) to the state is monitored by a filtered photomultiplier tube and a lock-in amplifier. Compared with previous studies [C.C. Tsai, J.T. Bahns, W.C. Stwalley, J. Chem. Phys. 99 (1993) 7417], a wider range of rotational quantum numbers of data field are observed. A set of Dunham coefficients and the Rydberg-Klein-Rees potential energy curve of the 31Πg state are deduced from all the observed rovibrational levels. 相似文献
11.
通过显微光致发光技术和显微拉曼(Raman)技术研究了半绝缘GaAs (SI-GaAs)晶体的带边附近的发光. 在光荧光谱中,观察到在高于GaAs带边0.348eV处有一个新的荧光峰. 结合Raman谱指认此发光峰来源于GaAs的E0+Δ0能级的非平衡荧光发射. 同时, 通过研究E0+Δ0能级的偏振、激发光强度依赖关系,以及温度依赖关系说明E0+Δ0能级与带边E0共享了共同的导带位置Γ6,同时这也说明在GaAs中主要是导带的性质决定了材料的光学行为.同时,通过与n-GaAs和δ掺杂GaAs相比较,半绝缘GaAs晶体的E0+Δ0能级的发光峰更能反映GaAs电子能级高临界点E0+Δ0的能量位置和物理性质. 研究结果说明显微光致发光技术是研究半导体材料带边以上能级光学性质的一种非常有力的研究工具.
关键词:
半绝缘GaAs
显微光致发光
自旋轨道分裂 相似文献
12.
考虑系统噪声和时滞,利用L2—L∞控制理论研究了有leader的二阶定拓扑多智能体系统的协调一致问题.工程应用中控制输出的极大值经常需控制在一定范围内,并且考虑系统对位置变量和速度变量限制的范围不同,分别针对位置和速度的控制输出设计了加权系数;进而建立了多智能体系统的数学模型.对有时滞和无时滞的两种网络拓扑,利用李亚普诺夫函数,分析了多智能体系统在满足L2—L∞性
关键词:
L2—L∞控制')" href="#">L2—L∞控制
多智能体系统
一致问题
时滞 相似文献
13.
本文在多通道量子数亏损理论(MQDT)框架下,利用相对论多通道理论(RMCT),分别在冻结实近似、 考虑Δl=-1的偶极极化效应、Δl=+1的偶极极化效应、Δl=± 1的偶极极化效应、伸缩模效应以及同时考虑偶极极化效应和伸缩模效应等不同层次近似下,系统地计算了碱金属Li, Na, K, Rb, Cs和Fr七个里德伯系列的能级,即ns2S1/2, np2P1/2, np2P3/2, nd2D3/2, nd2D5/2, nf2F5/2 和nf2F7/2.计算结果表明,电子关联效应对碱金属原子的里德伯能级的影响很大.总的来说,偶极极化效应比伸缩模效应重要,而在偶极极化效应中, Δl = + 1的偶极极化效应比Δl = - 1的偶极极化效应重要.但对于Na的ns2S1/2,(nd2D3/2,nd2D5/2)里德伯系列的能级,和Li的(np2P1/2,np2P3/2)里德伯系列的能级,是伸缩模效应比较重要. 相似文献
14.
Per Jensen 《Journal of Molecular Spectroscopy》1984,104(1):59-71
The semirigid bender Hamiltonian for carbon su?ide C3O2 [P. R. Bunker, J. Mol. Spectrosc.80, 422–437 (1980)] is extended in a manner similar to the extension previously described for HCNO [P. Jensen, J. Mol. Spectrosc.101, 422–439 (1983)]. The extended Hamiltonian describes the manifold of large-amplitude vibrational states (due to the ν7 CCC bending mode) superimposed on a high-frequency vibrational state involving excited quanta of the CCO bending modes ν5 and ν6. The extended model is used to fit CCC bending and rotation energy level separations for12C316O2 superimposed on the ν5 fundamental level. Due to the severely limited experimental data it is not possible to unambiguously determine the effective CCC bending potential energy function in the ν5 state, but estimates of the potential energy parameters are obtained by determining them in two limiting cases. 相似文献
15.
L. A. Kondratyuk E. L. Bratkovskaya V. Yu. Grishina M. Büscher W. Cassing H. Str?her 《Physics of Atomic Nuclei》2003,66(1):152-171
We consider near-threshold a
0(980)-meson production in πN and NN collisions. An effective Lagrangian approach with one-pion exchange is applied to analyze different contributions to the
cross section for different isospin channels. The Reggeon exchange mechanism is also evaluated for comparison. The results
from πN reactions are used to calculate the contribution of the a
0 meson to the cross sections and invariant
mass distributions of the reactions
and pp → ppK
+
K
−. It is found that the experimental observation of a
0
+
mesons in the reaction
is much more promising than the observation of a
0
0
mesons in the reaction pp → ppK
+
K
−. Effects of isospin violation in the reactions pN → da
0, pd → 3He(3H)a
0, and dd → 4Hea
0, which are induced by a
0(980)-f
0(980) mixing, are also analyzed.
From Yadernaya Fizika, Vol. 66, No. 1, 2003, pp. 155–174.
Original English Text Copyright ? 2003 by Kondratyuk, Bratkovskaya, Grishina, Büscher, Cassing, Str?her.
This article was submitted by the authors in English. 相似文献
16.
采用中红外波段连续可调谐二极管激光器和自行研制的低温吸收池, 测量了温度为296 K, 252 K, 213 K, 173 K时, 3.38 μm附近13CH4分子的四条跃迁谱线的氮气和空气加宽光谱; 首次通过实验获得空气和氮气对13CH4分子的碰撞加宽系数, 以及谱线加宽系数的温度依赖系数. 实验过程中, 利用Voigt线型对所测量的光谱进行拟合. 实验结果表明, 氮气和空气对13CH4分子的碰撞诱导加宽系数随温度的降低而增大; 相同温度下, 氮气对13CH4分子的碰撞加宽系数普遍大于空气加宽系数. 实验数据为地球和外星体大气遥感探测提供了依据. 相似文献
17.
本文用X射线粉末法测定了Li2K(IO3)3与Li2NH4(IO3)3的晶体结构和原子参数。发现Li3K(IO3)3,Li2NH4(IO3)3与Li2Rb(IO3)3同晶型,属单斜晶系,空间群为P21/α,每个单胞含有四个化合式量。室温的点阵常数分别为α=11.198?,b=11.046?,c=8.254?,β=111.53°,及α=11.327?,b=11.078?,c=8.341?,β=111.87°。讨论了二元化合物的形成与离子半径的关系。
关键词: 相似文献
18.
Michael A. Lawson Kristian J. Hoffman Paul B. Davies 《Journal of Molecular Spectroscopy》2011,269(1):61-76
The asymmetric stretching fundamental of the PO2 free radical in its ground electronic state has been measured between 1280 and 1360 cm−1 using diode laser absorption spectroscopy. This new data set has been combined in a fit with an earlier, smaller infrared data set and with pure rotational transitions measured by microwave and laser magnetic resonance spectroscopies to provide a new set of parameters for the ground and ν3 = 1 states of A1 PO2. These parameters can be used to calculate line positions in this band for transitions up to N = 50. 相似文献
19.
20.
C. L. Bell M. Dhib G. Hancock G. A. D. Ritchie J. H. van Helden N. J. van Leeuwen 《Applied physics. B, Lasers and optics》2009,94(2):327-336
Cavity enhanced absorption spectroscopy is performed using an external cavity diode laser operating around 1516 nm. We demonstrate
a sensitivity of 6×10−8 cm−1 Hz−1/2 and utilise a simple method to measure pressure-induced broadening and shift coefficients. The broadening and shift coefficients
for six gases (helium, neon, argon, xenon, oxygen and nitrogen) have been determined at room temperature for four transitions
in the υ
1+υ
3 combination band of ammonia. Comparisons of the broadening coefficients with previous work in this region, where it exists,
show good agreement. The broadening and shift coefficients of nitrogen and oxygen are also in good agreement with calculated
values using the Robert and Bonamy theory. Both the broadening and shift coefficients show a clear trend through the rare
gases, which can be explained in terms of the varying magnitude of the long range attractive forces operating between the
colliding partners. We also demonstrate the application of the Parmenter–Seaver formalism to estimate the potential well depth
of the ammonia dimer from the obtained broadening coefficients. The obtained well depth agrees well with theoretical calculations. 相似文献