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1.
CMS physicists need to seamlessly access their experimental data and results,independent of location and storage medium,in order to focus on the exploration for the new physics signals arther than the complexities of worldwide data management .In order to achieve this goal,CMS has adopted a tiered worldwide computing model which will incorporate emerging Grid technology.CMS has started to use Grid tools for data processing,replication and migration,Important Grid components are expected to be delivered by the Data Grid projects.like projects,CMS has created a set of long-term requirements to the Grid projects.These requirements are presented and discussed.  相似文献   

2.
StudyontheLevelMonitoringSystemfortheShipcariageboxWANGBaoguang(TianjinUniversity,Tianjin300072,China)GENGShijun(HebeiIndus...  相似文献   

3.
4.
We discuss the potential of the neutron Lloyd’s mirror interferometer in a search for new interactions at small scales. We consider three hypothetical interactions that may be tested using the interferometer. The chameleon scalar field proposed to solve the enigma of accelerating expansion of the Universe produces interaction between particles and matter. The axion-like spin-dependent coupling between a neutron and nuclei or/and electrons may result in a P- and T-noninvariant interaction with matter. Hypothetical non-Newtonian gravitational interactions mediates an additional short-range potential between neutrons and bulk matter. These interactions between the neutron and the mirror of a Lloyd-type neutron interferometer cause a phase shift of neutron waves. We estimate the sensitivity and systematic effects of possible experiments.  相似文献   

5.
The main goal of the HyperCP(E87) experiment at Fermilab is to search for CP violation in Ξand Α decays at the -10^-4 level.This level of precision dictates a data sample of over a billion events.The experiment collected about 231 billion raw events on about 30,000 5-GB tapes in ten months of running in 1997and 1999,In order to analyze this huge amount of data,the collaboration has reconstructed the events on a farm of 55 dual-processor Linux-based PCs at Fermilab.A set of farm tools has been written by the collaboration to interface with the Farm Batch System (FBS and FBSNG)[1] developed by the Fermilab Computing Division,to automate much of the farming and to allow nonexpert farm shifters to submit and monitor jobs through a web-based interface.Special care has been taken to produce a robust system which facilitates easy recovery from errors.The code has provisions for extensive monitoring of the data on a spill-by-spill basis,as is required by the need to minimize potential Systematic errors.About 36 million plots of various parameters produced from the farm analysis can be accessed through a data management system.The entire data set was farmed in eleven mouths,or about the same time that was taken to acquire the data.We will describe the architecture of the farm.our experience in operating it ,and show some results from the farm analysis.  相似文献   

6.
Based on the spectral problem associated with the TD hierarchy, a recursion relation for the adjoined spectral problem is obtained, by which the TD hierarchy is transformed into the modified one. As a special example, the first nontrivial member in the modified hierarchy is reduced to an integrable Heisenberg spin equation.  相似文献   

7.
In a number of scaling limits, we prove estimates relating the solutions of the Camassa–Holm equation to the solutions of the associated KdV equation. As a consequence, suitable solutions of the water wave problem and solutions of the Camassa–Holm equation stay close together for long times.  相似文献   

8.
《Nuclear Physics B》1988,295(4):571-585
The dispersion expansion for the two-point electric correlation function in the eight-vertex model is calculated to first order in the four-spin coupling in the scaling limit in the high-temperature regime. It is found that there is a close relation between the Tc and Tc+ spin-spin-energy density correlation function in the Ising model. This is used to simplify tremendously the calculation in the Tc+ case; the result can be obtained from the Tc result by deleting two variables in the expansion.  相似文献   

9.
Abstract

The B¨acklund transformations for the relativistic lattices of the Toda type and their discrete analogues can be obtained as the composition of two duality transformations. The condition of invariance under this composition allows to distinguish effectively the integrable cases. Iterations of the B¨acklund transformations can be described in the terms of nonrelativistic lattices of the Toda type. Several multifield generalizations are presented.  相似文献   

10.
We show that the -functions obtained from Schur polynomials lead to wave functions w(x 1, x 2, ... ; k) that possess the following bispectral property: There exists a differential operator B{k,k}, independent of x 1 , such that B{k,k}w = {x 1}w, where {x 1} is independent of k. This extends for the KP hierarchy some earlier results of J. J. Duistermaat and F. A. Grünbaum for the rational solutions of KdV and of P. Wright for certain rational solutions of the generalized KdV equations.  相似文献   

11.
In this paper, the Hierarchical Model is studied near a non-trivial fixed point of its renormalization group. Our analysis is an extension of work of Bleher and Sinai. We prove the validity of the -expansion for . We then show that the renormalization transformations around have an unstable manifold which is completely characterized by the tangent map and can be brought to normal form. We then establish relations between this result and the critical behaviour of the model in the thermodynamic limit.  相似文献   

12.
A search for the doubly charmed baryon Ξ_(cc)~+ is performed through its decay to the Λ_c~+K~-π~+ final state, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 Te V. The data correspond to a total integrated luminosity of 9 fb~(-1). No significant signal is observed in the mass range from 3.4 to 3.8 Ge V/c~2. Upper limits are set at 95% credibility level on the ratio of the Ξ_(cc)~+ production cross-section times the branching fraction to that of Λ_c~+ and Ξ_(cc)~(++) baryons. The limits are determined as functions of the Ξ_(cc)~+ mass for different lifetime hypotheses, in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15 GeV/c.  相似文献   

13.
We investigate a common used algorithm [Phys. Rev. E 64 (2001) 016132] to calculate the betweenness centrality for all vertices. The inaccurateness of that algorithm is pointed out and a corrected algorithm, also with O(MN) time complexity, is given. In addition, the comparison of calculating results for these two algorithm aiming at the protein interaction network of yeast is shown.  相似文献   

14.
In the present study, twenty-five samples of red blood cells (RBCs) and two samples of lyophilized serum, drawn from thirteen patients with -thanassemia major, have been examined by Mössbauer spectroscopy. All these patients undergo long-term therapy by regular blood transfusion and deferoxamine. The samples were obtained at the end of one cycle of treatments, before the successive blood transfusion. The results show, within the experimental errors, that the ferritin-like iron appears to be absent in the RBCs of the patients but it is still present in the serum.On leave from Tsinghua University, Beijing, PR China.On leave fro East China Normal University, Shanghai, PR China.  相似文献   

15.
We derive an equation satisfied by the dissipation rate correlation function, for the homogeneous, isotropic state of fully-developed turbulence from the the Navier–Stokes equation. In the equal time limit we show that the equation leads directly to two intermittency exponents 1=2– 6 and 2=z4 4, where the 's are exponents of velocity structure functions and z4 is a dynamical exponent characterizing the fourth order structure function. We discuss the contributions of the pressure terms to the equation and the consequences of hyperscaling.  相似文献   

16.
ABSTRACT

The widespread idea that spin-density functional theory is based upon the extension of the Hohenberg–Kohn theorem to weak magnetic fields is contested. First, it is assumed that only the term linear in magnetic field can be kept in the Hamiltonian. Second, once this is done, two problems arise (1) not only the spin-dependent, but also the orbital-dependent term should be taken care of, and (2) the latter produces eigenvalues that are not bounded from below, thus invalidating the proof of the Hohenberg–Kohn theorem.  相似文献   

17.
《Physics letters. A》1988,131(1):8-10
A new derivation of the Feynman propagator for the Dirac δ-function potential is presented.  相似文献   

18.
We present Finslerian perturbation for the ΛCDM model, which breaks the isotropic symmetry of the universe. The analysis on the Killing vectors shows that the Randers–Finsler spacetime breaks the isotropic symmetry even if the scalar perturbations of the FRW metric vanish. In Randers–Finsler spacetime, the modified geodesic equation deduces a modified Boltzmann equation. We propose a perturbational version of the gravitational field equation in Randers–Finsler spacetime, where we have omitted the curvature tensor that does not belong to the base space of the tangent bundle. The gravitational field equations for the gravitational wave are also presented. The primordial power spectrum of the gravitational wave is investigated. We show that the primordial power spectrum for super-horizon perturbations is unchanged. For sub-horizon perturbations, however, the power spectrum is modified.  相似文献   

19.
New, physically motivated static sources for the Reissner-Nordström metric are found. One is a generalization of the Schwarzschild interior solution representing a sphere of constant nongravitational energy density. The other is a family of solutions for which the mass is electromagnetic in origin. Some general results are found. For a charged fluid sphere in equilibrium with pressure,m 2 >q 2. For a charged body with equation of state = (p), where (0)=0, the body is under tension at every point when the charge density has the same sign throughout.Supported by the National Research Council of Canada, Grant No. A5340.  相似文献   

20.
BEPCⅡ—an upgrade project of Beijing Electron Positron Collider (BEPC) is a factory type of e+e- collider. It requires its injector linac to have a higher beam energy (1.89 GeV) for on-energy injection and a higher beam current (40 mA e+ beam) for a higher injection rate ( 50 mA/min). The low beam emittance (1.6π mm·mrad for e+ beam, and 0.2πmm·mrad for 300 mA e- beam) and the low beam energy spread (±0.5%) are also required to meet the storage ring acceptance. Thus the original BEPC injector linac must be upgraded to have a new electron gun with its complete tuning system, a new positron source with a flux concentrator, a new RF power system with its phasing loops and a new beam tuning system with orbit correction and optics tuning devices. These new components have been designed, fabricated, tested and will be installed in their final positions in this spring and summer, which are described in this paper.  相似文献   

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