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91.
The minimal supersymmetric extension of the standard model (MSSM) predicts the existence of new charged and neutral Higgs
bosons. The pair creation of these new particles at the multi-TeV e
+
e
− compact linear collider (CLIC), followed by decays into standard model particles, were simulated along with the corresponding
background. High-energy beam-beam effects such as ISR, beamstrahlung and hadronic background were included. We have investigated
the possibility of using the ratio between the number of events found in various decay channels to determine the MSSM parameter
tan β and we have derived the corresponding statistical error from the uncertainties on the measured cross-sections and Higgs boson
masses.
相似文献
92.
WANG Shao-Ming HAN Liang MA Wen-Gan ZHANG Ren-You JIANG Yi 《理论物理通讯》2007,48(3):491-501
We investigate the lepton flavor violating productions pp/pp→eμ + X in the framework of the R-parity violating (RPV) supersymmetric model at the Tevatron and the CERN large hadron collider (LHC). We present the total cross sections including the next-to-leading order (NLO) QCD corrections and the contribution from gluon-gluon fusion subprocess. Our numerical results show that the one-loop QCD corrections significantly increase the tree-level cross sections, and the variation of K factor is in the range between 1.28 (1.32) and 1.79 (1.58) at the Tevatron (LHC). We find that the QCD correction from the one-loop gluon-gluon fusion subprocess is remarkable at the LHC and should be taken into account. 相似文献
93.
We consider the possibility of using the quantum inverse scattering method to study the superconformal field theory and its integrable perturbations. The classical limit of the considered constructions is based on the
(1|2) super-KdV hierarchy. We introduce the quantum counterpart of the monodromy matrix corresponding to the linear problem associated with the L-operator and use the explicit form of the irreducible representations of
q(1|2) to obtain the fusion relations for the transfer matrices (i.e., the traces of the monodromy matrices in different representations).Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 142, No. 2, pp. 252–264, February, 2005. 相似文献
94.
根据超对称量子力学及其与(1+2)维时空中费米子与规范场相互作用的 Dirac 方程的等价性求出了在强磁场中作相对论性运动的二维电子的能级和能量本征函数.所得结果将有助于量子Hall 效应的理论研究. 相似文献
95.
Crivelli S Kreylos O Hamann B Max N Bethel W 《Journal of computer-aided molecular design》2004,18(4):271-285
We describe ProteinShop, a new visualization tool that streamlines and simplifies the process of determining optimal protein folds. ProteinShop may be used at different stages of a protein structure prediction process. First, it can create protein configurations containing secondary structures specified by the user. Second, it can interactively manipulate protein fragments to achieve desired folds by adjusting the dihedral angles of selected coil regions using an Inverse Kinematics method. Last, it serves as a visual framework to monitor and steer a protein structure prediction process that may be running on a remote machine. ProteinShop was used to create initial configurations for a protein structure prediction method developed by a team that competed in CASP5. ProteinShop's use accelerated the process of generating initial configurations, reducing the time required from days to hours. This paper describes the structure of ProteinShop and discusses its main features. 相似文献
96.
We show that the positive supersymmetric matrix-valued differential operator H = p
x
2 + p
y
2 + x
2
y
2 + x3 + y1 has no zero modes, i.e., H = 0 implies = 0. The result depends on a virial type argument for the corresponding supercharge. The model may be regarded as a simple relative of dimensional reductions of supersymmetric Yang–Mills theories. 相似文献
97.
We find that in a supersymmetric quantum mechanics (SUSY QM) system, in addition to supersymmetric algebra, an associated SU(2) algebra can be obtained by using semiunitary (SUT) operator and projection operator, and the relevant constants of motion can be constructed. Two typical quantum systems are investigated as examples to demonstrate the above finding. The first example is the quantum system of a nonrelativistic charged particle moving in x-y plane and coupled to a magnetic field along z axis. The second example is provided with the Dirac particle in a magnetic field. Similarly there exists an SUτ(2) \otimes SUσ(2) symmetry in the context of the relativistic Pauli Hamiltonian squared. We show that there exists also an SU(2) symmetry associated with the supersymmetry of the Dirac particle. 相似文献
98.
《中国颗粒学报》2008,6(6)
We use a two-dimensional model of polygonal particles to investigate granular ratcheting. Ratcheting is a long-term response of granular materials under cyclic loading, where the same amount of permanent deformation is accumulated after each cycle. We report on ratcheting for low frequencies and extremely small loading amplitudes. The evolution of the sub-network of sliding contacts allows us to understand the micromechanics of ratcheting. We show that the contact network evolves almost periodically under cyclic loading as the sub-network of the sliding contacts reaches different stages of anisotropy in each cycle. Sliding contacts lead to a monotonic accumulation of permanent deformation per cycle in each particle. The distribution of these deformations appears to be correlated in form of vortices inside the granular assembly. 相似文献
99.
We use a two-dimensional model of polygonal particles to investigate granular ratcheting. Ratcheting is a long-term response of granular materials under cyclic loading, where the same amount of permanent deformation is accumulated after each cycle. We report on ratcheting for low frequencies and extremely small loading amplitudes. The evolution of the sub-network of sliding contacts allows us to understand the micromechanics of ratcheting. We show that the contact network evolves almost periodically under cyclic loading as the sub-network of the sliding contacts reaches different stages of anisotropy in each cycle. Sliding contacts lead to a monotonic accumulation of permanent deformation per cycle in each particle. The distribution of these deformations appears to be correlated in form of vortices inside the granular assembly. 相似文献
100.
Solving Two Kinds of JC Models Relating to Two-Photon Process by
Supersymmetric Transformation 总被引:2,自引:0,他引:2
FANHong-Yi GUIWei-Jun 《理论物理通讯》2004,42(2):193-196
We propose two kinds of new Jaynes Cummings models relating to two-photon process by using the supersymmetric unitary transformation. The corresponding energy eigenvalues and eigenvectors are obtained. 相似文献