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1.
The preliminary results on the tensor T20 analyzing power for the 12C(,p)13C* reaction with the excitation of 13C levels and the d(,p)X reaction at the energies T d = 140, 200 and 270 MeV at the emission angle Θ cm = 0° are presented. The data on the tensor A yy and vector A y analyzing powers for the 12C(,p)13C* reaction at the energy T d = 270 MeV in the angular range from 4° to 18° in the laboratory are also obtained.  相似文献   

2.
The paper is devoted to the calculation of two-loop (α s 2) MSSM corrections to the relation between the pole mass of the t quark and its running mass in the scheme. Firstly, the value of the second-order contribution from large-mass expansion in mt/M SUSY is studied. Contrary to our expectations, this contribution turned out to be negligible. As a by-product of this calculation, the two-loop anomalous dimension of the running quark mass is obtained in the supersymmetric QCD. Secondly, the influence of the two-loop corrections to the t-quark mass on the predicted superpartner masses is investigated. The text was submitted by the authors in English.  相似文献   

3.
New experimental data on inclusive cross section of neutral-vector-meson (ω 0, ϕ, K S 0) production in proton-proton collisions at = 200 GeV obtained at RHIC are analyzed in the framework of z scaling. Properties of z-presentation are used to predict hadron yields over a wide range of transverse momentum p T and collisions energy . The next-to-leading-order perturbative QCD calculations of inclusive cross sections of π 0 mesons produced in pp and collisions over a wide range of and p T are compared with ISR, S pS, RHIC data and predictions of z scaling. The dependence of the spectra in p T and z presentations for different parton distribution and fragmentation functions is studied. The sensitivity of the obtained results to the choice of the renormalization (μ R ), initial-state factorization (μ F ), and final-state factorization (fragmentation) (μ H ) scales is verified. It is shown that self-similar features of particle production dictated by the z scaling give strong restriction on the asymptotic behavior of the inclusive spectra in high-p T region. The text was submitted by the author in English.  相似文献   

4.
Prospects for observation of a SUSY-like signal from two gluinos are investigated within a certain region of the mSUGRA parameter space, where the cross section of the two-gluino production in pp-collisions at the LHC ( = 14 TeV) is estimated at a rather high level of 17.3 pb. In this so-called EGRET-preferred region, the lightest stable neutralinos χ 10 can serve as cold-dark-matter particles and can naturally explain the excess of diffuse Galactic gamma rays observed by the EGRET space apparatus. The -event selection relies on a clear signature when decay products of each gluino contain one b pair, one or two l pair(s) or one or two light q pair(s), and a neutralino. Rather high transverse missing energy carried away by the two neutralinos is the essential signature of the events using of which allows the relevant Standard Model background to be reduced significantly. Furthermore, distributions of the reconstructed invariant masses of two opposite-charged-lepton or light-jet pairs produced by the χ 20χ 10 l + l and χ 20χ 10 q three-body decays have kinematic end points which measure the difference between masses of χ 20 and χ 10. In particular, it was found that these signatures of selected processes demonstrate good prospects for discovery of gluinos at the LHC. These signatures allow one to distinguish different mSUGRA parameters m 1/2 within the EGRET-preferred region (at a higher than 6σ confidence level with 300 fb−1 data). The text was submitted by the authors in English.  相似文献   

5.
The data on the vector A y and tensor A yy , A xx , A xz analyzing powers for the d3H p reaction have been obtained at the energy of the initial deuteron of 200MeV in the angular range of 0–95 degrees in the c.m.s. The calculations performed within one-nucleon exchange model with the use of the standard three-nucleon bound state wave functions fail to reproduce the data on the tensor analyzing powers.  相似文献   

6.
Phenomenological issues of CP violation in the quark sector of the Standard Model are discussed. We consider quark mixing in the SM, standard, and Wolfenstein parametrization of the CKM mixing matrix and unitarity triangle. We discuss the phenomenology of CP violation in K L 0 and B d 0()-decays. The standard unitarity triangle fit of the existing data is discussed. In appendix A we compare the K 0 ⇆ , B d,s 0 ⇆ , etc. oscillations with neutrino oscillations. In Appendix B we derive the evolution equation for the M − system in the Weisskopf-Wigner approximation. The text was submitted by the author in English.  相似文献   

7.
A trajectory attractor is constructed for the 2D Euler system containing an additional dissipation term −ru, r > 0, with periodic boundary conditions. The corresponding dissipative 2D Navier-Stokes system with the same term −ru and with viscosity v > 0 also has a trajectory attractor, . Such systems model large-scale geophysical processes in atmosphere and ocean (see [1]). We prove that → as v → 0+ in the corresponding metric space. Moreover, we establish the existence of the minimal limit of the trajectory attractors as v → 0+. We prove that is a connected invariant subset of . The connectedness problem for the trajectory attractor by itself remains open. Dedicated to the memory of Leonid Volevich Partially supported by the Russian Foundation for Basic Research (projects no 08-01-00784 and 07-01-00500). The first author has been partially supported by a research grant from the Caprio Foundation, Landau Network-Cento Volta.  相似文献   

8.
First principles should predetermine physical geometry and dynamics both together. In the “algebrodynamics” they follow solely from the properties of biquaternion algebra and the analysis over . We briefly present the algebrodynamics over Minkowski background based on a nonlinear generalization to of the Cauchi-Riemann analyticity conditions. Further, we consider the effective real geometry uniquely resulting from the structure of multiplication and found it to be of the Minkowski type, with an additional phase invariant. Then we pass to study the primordial dynamics that takes place in the complex space and brings into consideration a number of remarkable structures: an ensemble of identical correlated matter pre-elements (“duplicons”), caustic-like signals (interaction carriers), a concept of random complex time resulting in irreversibility of physical time at macrolevel, etc. In partucular, the concept of “dimerous electron” naturally arises in the framework of complex algebrodynamics and, together with the above-mentioned phase invariant, allows for a novel approach to explanation of quantum interference phenomena alternative to recently accepted wave—particle dualism paradigm. The text was submitted by the author in English.  相似文献   

9.
The reaction 54Fe(, p)55Fe was studied at the Munich Q3D spectrograph with a 14MeV polarized deuteron beam. Excitation energies, angular distributions and analyzing powers were measured for 39 states up to 4.5MeV excitation energy. Spin and parity assignments were made and spectroscopic factors deduced by comparison to DWBA calculations. The results were compared to predictions by large-scale shell model calculations in the full pf -shell and it was found that reasonable agreement for energies and spectroscopic factors below 2.5MeV could only be obtained if up to 6 particles were allowed to be excited from the f 7/2 orbital into p 3/2 , f 5/2 , and p 1/2 orbitals across the N = 28 gap. For levels above 2.5MeV the experimental strength distribution was found to be significantly more fragmented than predicted by the shell model calculations.  相似文献   

10.
A general formalism for double and triple spin correlations of the reaction is developed for the case of collinear kinematics. A complete polarization experiment allowing one to reconstruct all four amplitudes describing this process is suggested. Furthermore, the spin observables of the inelastic charge-exchange reaction (pp)(1 S 0 are analyzed in collinear kinematics within the single pN-scattering mechanism involving the subprocess pn → Δ0 p. The full set of spin observables, related to the polarization of one or two initial particles and one final particle, is obtained in terms of three invariant amplitudes of the reaction pd → Δ(pp)(1 S 0) and the transition form factor d → (pp)(1 S 0). A complete polarization experiment for the reaction (pp)(1 S 0) is suggested which allows one to determine three independent combinations of the four amplitudes of the elementary subprocess . The text was submitted by the authors in English.  相似文献   

11.
Z. Y. Turakulov 《Pramana》2009,72(3):473-479
In mechanics of the mass point passage from one frame of reference to another moving with velocity consists in subtracting this vector from the velocity of the particle. In general case the vector is not constant, as, for example, when passing through a rotating frame, this operation creates inertial forces. Analysis of this phenomenon from the point of view of Lagrangian and Hamiltonian mechanics is interesting from the general relativistic point of view due to Einstein’s principle of equivalence. We show that the vector plays the role of vector potential which, however, essentially differs from vector potential known in classical electrodynamics. Comparative analysis of the two kinds of vector potentials is completed.   相似文献   

12.
We present results for the universal anomalous dimension γ uni(j) of Wilson twist-2 operators in the = 4 supersymmetric Yang-Mills theory in the first four orders of perturbation theory. The text was submitted by the authors in English.  相似文献   

13.
The leptonic () decay of a heavy quark-antiquark bound state T( Q) with a Higgs-boson H emission is investigated. Applying the low-energy theorem to meson-Higgs coupling allows one to estimate the probability of the decay T( Q) → H. Only the simple version of the Standard Model extension containing two-Higgs doublet is considered. The text was submitted by the author in English.  相似文献   

14.
Prospects for observing a SUSY-like signal from two gluinos are investigated within a certain region of the mSUGRA parameter space, where the cross section of the two gluino production in pp collisions at the LHC ( = 14 TeV) via gluon-gluon fusion (gg → ) is estimated at a rather high level of 17.3 pb. In this so-called EGRET region, the lightest stable neutralinos can serve as cold dark matter particles and are natural explanations of the excess of diffuse galactic gamma rays observed by the EGRET space apparatus. The -event selection relies on a very clear signature when decay products of each gluino contain one b-anti-b pair, one or two lepton-antilepton pair(s) and a neutralino. Rather high transverse-missing energy, carried away by the two neutralinos, is an essential signature of the events and also allows the relevant Standard Model background to be reduced significantly. In particular, it was found that the clear signatures of the selected processes demonstrate good prospects discovering the EGRET gluinos at the LHC. Furthermore, these signatures allow one to distinguish different mSUGRA parameters m 1/2 inside the EGRET region. The text was submitted by the authors in English.  相似文献   

15.
There is a natural cancellation between the contributions of the qqq and qqqq components to the axial charge of the N(1535)-resonance. While the probability of the former is larger than that of the latter, its coefficient in the axial charge expression is exceptionally small. The magnitude of two of the corresponding coefficients of the qqqq components is in contrast large and has the opposite sign. This result provides a phenomenological illustration of the recent unquenched lattice calculation result that the axial charge of the N(1535)-resonance is very small, if not vanishing (T.T. Takahashi, T. Kunihiro, arXiv: 0801.4707 [hep-lat]). The result sets an upper limit on the magnitude of the probability of qqqq components as well.  相似文献   

16.
We prove a maximal regularity result for operators corresponding to rotation invariant symbols (in space) which are inhomogeneous in space and time. Symbols of this type frequently arise in the treatment of half-space models for (free) boundary-value problems. The result is obtained by extending the Newton polygon approach to variables living in complex sectors and combining it with abstract results on the -calculus and -bounded operator families. As an application, we derive maximal regularity for the linearized Stefan problem with Gibbs-Thomson correction. Dedicated to the memory of Leonid Romanovich Volevich  相似文献   

17.
The new identifying problem is formulated for general linear functional operators F = Σc j Fa j which significantly generalizes in particular the well-known Ulam stability problem. The results obtained can be very useful when processing experimental data of any kind as they enable to determine with high precision the structure of a compactly supported Banach-valued function F by using a rather restricted information concerning F. Dedicated to the memory of Leonid Volevich  相似文献   

18.
The potential energy surfaces of the lowest electronic states $ \tilde X The potential energy surfaces of the lowest electronic states 2 A 1 and 2 B 1 of the CH2+ molecular ion are calculated in the second order of the perturbation theory with the reference function obtained by the multiconfiguration self-consistent-field method in the complete-active-space approximation. Based on the ab initio calculated potential energy surfaces, the rovibronic energies of CH2+ are calculated by the variational method using the RENNER Hamiltonian. It is found that the accuracy of the perturbation theory method involving many reference configurations is as good as the accuracy of the best ab initio calculations performed by the configuration interaction method with many reference configurations and by the coupled cluster method with a single reference configuration. Empirical refinement of the two parameters of the potential function leads to good agreement between calculation and experiment, except for the wavenumbers of the (0, 3, 0)1 ← (0, 0, 0)0 transitions. Original Russian Text ? V.G. Solomonik, A. Yu. Yachmenev, 2008, published in Optika i Spektroskopiya, 2008, Vol. 104, No. 6, pp. 904–910.  相似文献   

19.
For the kernel of the Laplace operator ΔΛ with potential Σ j=1 k c j δ q j (x) on a manifold, (the operator is given by a Lagrangian plane Λ ⊂ ℂ k ⊕ ℂ k ), an isomorphism Γ: ker ΔΛ → Λ ∩ L is described, where L is a special Lagrangian plane (whose explicit form is evaluated). A similar assertion holds for the Laplace operator on a decorated graph; for such a graph (obtained by decorating a connected finite graph with n edges and v vertices) with “continuity” conditions, the inequality 1 ≤ dimker ≤ nv + 2 is obtained. It is also proved that the quantity nv + 1-dim ker cannot reduce when adding new edges and manifolds. The first terms of the expansion of Tr(exp(-tH Λ)) are found. Dedicated to the memory of V. A. Geyler  相似文献   

20.
The influence of nuclear effects on the production of neutral strange particles (V 0) is investigated using the data obtained with SKAT propane-freon bubble chamber irradiated in the neutrino beam (with E v =3−30 GeV) at the Serpukhov accelerator. The mean multiplicity of V 0 particles in nuclear interactions, , is found to exceed significantly that in “quasideuteron” interactions, . The ratio of is larger than that for π mesons, . It is shown that the multiplicity gain of V 0 particles can be explained by intranuclear interactions of produced pions. The text was submitted by the authors in English.  相似文献   

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