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Quantum dense coding scheme via cavity decay  [PDF]
Zheng-Yuan Xue,You-Min Yi,Zhuo-Liang Cao
Physics , 2005, DOI: 10.1080/09500340600829333
Abstract: We investigate a secure scheme for implementing quantum dense coding via cavity decay and liner optics devices. Our scheme combines two distinct advantages: atomic qubit sevres as stationary bit and photonic qubit as flying bit, thus it is suitable for long distant quantum communication.
Analytic Perturbation Theory and Renormalization Scheme Dependence in Tau Decay  [PDF]
K. A. Milton,I. L. Solovtsov,V. I. Yasnov
Physics , 1998,
Abstract: We apply analytic perturbation theory in next-to-next-to-leading order to inclusive semileptonic $\tau$-decay and study the renormalization scheme dependence. We argue that the renormalization scheme ambiguity is considerably reduced in the analytic perturbation theory framework and we obtain a rather stable theoretical prediction.
Spectroscopic factors for alpha decay in the $N_pN_n$ scheme  [PDF]
Madhubrata Bhattacharya,Subinit Roy,G. Gangopadhyay
Physics , 2008, DOI: 10.1016/j.physletb.2008.06.023
Abstract: Lifetime values for alpha decay in even-even nuclei with $Z=84-98$ and $N=128-152$ have been calculated in the superasymmetric fission model. The interaction between the alpha particle and the daughter nucleus has been formed in the double folding approach using a density dependent NN interaction. The densities have been obtained using the Relativistic Mean Field formalism. The spectroscopic factors for the decays have been deduced and are shown to vary smoothly as a function of effective numbers of valence nucleons, $N_p$ and $N_n$ chosen with a suitable core. The implication of such a smooth behaviour has been discussed.
Strong coupling constant from $τ$ decay within renormalization scheme invariant treatment  [PDF]
J. G. Koerner,F. Krajewski,A. A. Pivovarov
Physics , 2000, DOI: 10.1103/PhysRevD.63.036001
Abstract: We extract a numerical value for the strong coupling constant \alpha_s from the \tau-lepton decay rate into nonstrange particles. A new feature of our procedure is the explicit use of renormalization scheme invariance in analytical form in order to perform the actual analysis in a particular renormalization scheme. For the reference coupling constant in the \MSsch-scheme we obtain \alpha_s(M_\tau)= 0.3184 \pm 0.0060_{exp} which corresponds to \al_s(M_Z)= 0.1184 \pm 0.0007_{exp} \pm 0.0006_{hq mass}. This new numerical value is smaller than the standard value from $\tau$-data quoted in the literature and is closer to \al_s(M_Z)-values obtained from high energy experiments.
Alpha Decay Processes under a Diproton, Dineutron and Deuteron Pairing Scheme  [PDF]
David Verrilli,Rafael Martín
Physics , 2011,
Abstract: In this paper we are able to justify the existence or no of photons emitted during $\alpha$ decay, based on the average half life times using the BCS superconductivity and superfluidity theories. The proposed model suggests two possible channels. A first channel where the protons and neutrons interact separately through a spin coupling, giving rise to diprotons and dineutrons which in turn interact through an isospin coupling to form an $\alpha$ particle, and a second channel where the protons and neutrons are treated as nucleons that interact through an isospin coupling, giving rise to deuterons, which in turn interact through a spin coupling to form an $\alpha$ particle. Due to the nature of the involved particles, the systems considered are homogeneous. For the second channel, the photon play a very important role for the possible escape of the $\alpha$ particle. Within these premises the half life times of a considerable number of heavy nuclei with spherical symmetry can be estimated with good experimental agreement.
Diquarks and the Semi-Leptonic Decay of $Λ_{b}$ in the Hybrid Scheme  [PDF]
Peng Guo,Hong-Wei Ke,Xue-Qian Li,Cai-Dian Lu,Yu-Ming Wang
Physics , 2005, DOI: 10.1103/PhysRevD.75.054017
Abstract: In this work we use the heavy-quark-light-diquark picture to study the semileptonic decay $\Lambda_b \to \Lambda_c+l+\bar{\nu}_l$ in the so-called hybrid scheme. Namely, we apply the heavy quark effective theory (HQET) for larger $q^2$ (corresponding to small recoil), which is the invariant mass square of $l+\bar\nu$, whereas the perturbative QCD approach for smaller $q^2$ to calculate the form factors. The turning point where we require the form factors derived in the two approaches to be connected, is chosen near $\rho_{cut}=1.1$. It is noted that the kinematic parameter $\rho$ which is usually adopted in the perturbative QCD approach, is in fact exactly the same as the recoil factor $\omega=v\cdot v'$ used in HQET where $v$, $v'$ are the four velocities of $\Lambda_b$ and $\Lambda_c$ respectively. We find that the final result is not much sensitive to the choice, so that it is relatively reliable. Moreover, we apply a proper numerical program within a small range around $\rho_{cut}$ to make the connection sufficiently smooth and we parameterize the form factor by fitting the curve gained in the hybrid scheme. The expression and involved parameters can be compared with the ones gained by fitting the experimental data. In this scheme the end-point singularities do not appear at all. The calculated value is satisfactorily consistent with the data which is recently measured by the DELPHI collaboration within two standard deviations.
配电网载波通信的衰耗分析  [PDF]
电力系统自动化 , 2000,
Abstract: 从讨论配网载波可靠性的角度对载波通信的通道衰耗进行了系统的分析,在现场试验的基础上建立了配电网数字网络载波通信的通道衰耗计算公式,分析了通道衰耗的构成及各衰耗环节的大小,并在对配电网自动化载波通信进行现场试验的基础上,定量地对配电网载波通道进行了计算,其结果与现场试验数据相符。结论是:变电站的介入衰耗是配电网载波信号的主要衰耗;而线路衰耗很小,可以忽略;配电变压器的泄漏衰耗、分支线路的分支衰耗及折射衰耗与其数量有关,通过相应公式可以估算。
衰荡腔测量中的腔参数选择  [PDF]
强激光与粒子束 , 2005,
Abstract: ?基于谐振腔失调灵敏度参量随腔长的变化关系,提出了一种衰荡腔,它是由共焦腔将腔长缩短为原来的0.73得到的稳定腔。根据光束传输规律和失调腔矩阵方法,以及光腔衰荡法测量原理和曲线拟合方法,建立了腔长、腔镜角度失调下光腔衰荡法的反射率测量模型。通过数值模拟,研究了这种稳定衰荡腔中,腔微小失调对反射率测量结果的影响,并与相同失调情况下共焦衰荡腔的测量结果进行了对比分析。结果表明,这种稳定腔用作衰荡腔,测量结果受腔镜角度失调影响较大,而受腔长失调影响小;其长度较短,便于工程应用;衍射损耗较小,测量精度高。
Scheme for Concentration of Unknown Greeberger--Horne--Zeilinger Entangled States via Cavity Decay
Scheme for Concentration of Unknown Greeberger-Horne-Zeilinger Entangled States via Cavity Decay

ZHANG Xiao-Wei,LIU Xiang,TANG Xiao-Fang,TANG You-Liang,

中国物理快报 , 2007,
Abstract: We present a scheme for entanglement concentration of an unknown atomic non-maximally entangled GHZ state via cavity decay. In the scheme, the atom trapped in a cavity is manipulated by laser field, so the maximally entangled GHZ state can be obtained by performing certain operation, which can be realized by illuminating the atom in a cavity. Our method is robust against spontaneous atomic decay.
物理学报 , 1964,
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