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1.
Physics of Atomic Nuclei - The secondary proton polarization and differential cross sections of the ( $$p,p^{\prime}$$ ) inelastic reaction on nuclei $${}^{9}$$ Be and $${}^{90}$$ Zr at the initial...  相似文献   

2.
Physics of Atomic Nuclei - This paper presents a phenomenological study of differential $$W^{+}/W^{-}$$ cross section ratios for $$W$$ -boson production in association with a jet through...  相似文献   

3.
Physics of Atomic Nuclei - Angular $$t$$ – $$\gamma$$ correlations measured earlier in the reaction $${}^{27}$$ Al $$(\alpha,t)^{28}$$ Si(2 $${}^{+}$$ ) occurring at $$E_{\alpha}=30.3$$ MeV...  相似文献   

4.
In this paper we investigate methods to study the $t\bar{t}$ Higgs coupling. The spin and CP properties of a Higgs boson are analysed in a model-independent way in its associated production with a $t\bar{t}$ pair in high-energy e + e ? collisions. We study the prospects of establishing the CP quantum numbers of the Higgs boson in the CP-conserving case as well as those of determining the CP-mixing if CP is violated. We explore in this analysis the combined use of the total cross section and its energy dependence, the polarisation asymmetry of the top quark and the up-down asymmetry of the antitop with respect to the top–electron plane. We find that combining all three observables remarkably reduces the error on the determination of the CP properties of the Higgs Yukawa coupling. Furthermore, the top polarisation asymmetry and the ratio of cross sections at different collider energies are shown to be sensitive to the spin of the particle produced in association with the top-quark pair.  相似文献   

5.
Physics of Atomic Nuclei - The coherent photoproduction of $$\pi^{0}\pi^{0}$$ and $$\pi^{0}\eta$$ on nuclei in the mass-number region of $$A\leqslant 7$$ is studied systematically over the range...  相似文献   

6.
Physics of Atomic Nuclei - Spectrum, radii, radial wave functions at origin, decay constants, and momentum widths for radial and orbital excited $$B_{c}$$ mesons are derived within non-relativistic...  相似文献   

7.
Physics of Atomic Nuclei - The results of experimental investigations devoted to initiating the promising nuclear fusion reaction $${}^{11}$$ B $$(p,3\alpha)$$ in picosecond laser plasmas at a...  相似文献   

8.
Physics of Atomic Nuclei - The results of experiments performed at a high-resolution magnetic spectrometer (MAVR) are presented. The differential production cross sections for oxygen isotopes in...  相似文献   

9.
10.
Using the method of laser-induced fluorescence in an atomic beam we have measured the hyperfine splitting constants, A and B, of the ground and excited states of the optical transition 4f 76s 2 8S $_{1/2}\to 4f^{7}$ 6s6p 6P5/2 (564.58 nm) for 151???155Eu isotopes. For all isotopes, the magnetic dipole constants of the 6P5/2 atomic level are determined to a precision better than 0.04%. The A and B constants for the ground state 8S7/2 of the radioactive 152,154,155Eu were obtained for the first time with a precision better than 0.5%. Our data along with previous ground state hyperfine structure measurements for the stable europium isotopes allow us to determine the hyperfine anomaly for mentioned Eu isotopes.  相似文献   

11.
The main features of coupled-channel ${\bar K}N$ dynamics near threshold and its repercussions in few-body $\bar K$ -nuclear systems are briefly reviewed highlighting the I?=?1/2 ${\bar K}NN$ system. For heavier nuclei, the extension of mean-field calculations to multi- $\bar K$ nuclear quasibound states is discussed focusing on kaon condensation.  相似文献   

12.
13.
Physics of Atomic Nuclei - Lowest energy spectrum of the $${}^{12}$$ C nucleus is analyzed in the 3 $$\alpha$$ -cluster model with a deep $$\alpha\alpha$$ potential of Buck, Friedrich and Wheatley...  相似文献   

14.
Physics of Atomic Nuclei - The active target with C, Si and Pb plates was irradiated in 70-GeV proton beam at U-70 accelerator. The signal (270 events) from $$\Sigma^{0}\to\Lambda^{0}+\gamma$$...  相似文献   

15.
Physics of Atomic Nuclei - A survey of experimental results on the level structure in the heavy helium isotope $${}^{6}$$ He that were obtained in reactions induced by stopped pion absorption in...  相似文献   

16.
The process p $ \bar{{p}}$ $ \rightarrow$ $ \Lambda_{c}^{+}$ $ \bar{{\Lambda}}_{c}^{-}$ is investigated within the handbag approach. It is shown to lowest order of perturbative QCD that, under the assumption of restricted parton virtualities and transverse momenta, the dominant dynamical mechanism, characterized by the partonic subprocess u $ \bar{{u}}$ $ \rightarrow$ c $ \bar{{c}}$ , factorizes in the sense that only the subprocess contains highly virtual partons, namely a gluon, while the hadronic matrix elements embody only soft scales and can be parameterized in terms of helicity flip and non-flip generalized parton distributions. Modelling the latter functions by overlaps of light-cone wave functions for the involved baryons we are able to predict cross-sections and spin correlation parameters for the process of interest.  相似文献   

17.
Physics of Atomic Nuclei - For the first time, a self-consistent method for studying second-order anharmonic effects within quantum many-body theory is applied to calculating probabilities for...  相似文献   

18.
19.
Consider the focussing cubic nonlinear Schrödinger equation in \({\mathbb{R}}^3\) :
$i\psi_t+\Delta\psi = -|\psi|^2 \psi. \quad (0.1) $
It admits special solutions of the form e itα ?, where \(\phi \in {\mathcal{S}}({\mathbb{R}}^3)\) is a positive (? > 0) solution of
$-\Delta \phi + \alpha\phi = \phi^3. \quad (0.2)$
The space of all such solutions, together with those obtained from them by rescaling and applying phase and Galilean coordinate changes, called standing waves, is the 8-dimensional manifold that consists of functions of the form \(e^{i(v \cdot + \Gamma)} \phi(\cdot - y, \alpha)\) . We prove that any solution starting sufficiently close to a standing wave in the \(\Sigma = W^{1, 2}({\mathbb{R}}^3) \cap |x|^{-1}L^2({\mathbb{R}}^3)\) norm and situated on a certain codimension-one local Lipschitz manifold exists globally in time and converges to a point on the manifold of standing waves. Furthermore, we show that \({\mathcal{N}}\) is invariant under the Hamiltonian flow, locally in time, and is a centre-stable manifold in the sense of Bates, Jones [BatJon]. The proof is based on the modulation method introduced by Soffer and Weinstein for the L 2-subcritical case and adapted by Schlag to the L 2-supercritical case. An important part of the proof is the Keel-Tao endpoint Strichartz estimate in \({\mathbb{R}}^3\) for the nonselfadjoint Schrödinger operator obtained by linearizing (0.1) around a standing wave solution. All results in this paper depend on the standard spectral assumption that the Hamiltonian
$\mathcal H = \left ( \begin{array}{cc}\Delta + 2\phi(\cdot, \alpha)^2 - \alpha &;\quad \phi(\cdot, \alpha)^2 \\ -\phi(\cdot, \alpha)^2 &;\quad -\Delta - 2 \phi(\cdot, \alpha)^2 + \alpha \end{array}\right ) \quad (0.3)$
has no embedded eigenvalues in the interior of its essential spectrum \((-\infty, -\alpha) \cup (\alpha, \infty)\) .
  相似文献   

20.
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