BCVEGPY2.0: A upgrade version of the generator BCVEGPY with an addendum about hadroproduction of the PP-wave BcB_c states

The generator BCVEGPY is upgraded by adding the hadroproduction of the $P$-wave excited $B_c$ states (denoted by $B_{cJ,L=1}^*$ or by $h_{B_c}$ and $\chi_{B_c}$) and by improving some features of the original one as well. We denote it as BCVEGPY2.0. The $P$-wave production is also calculated by taking only the dominant gluon-gluon fusion mechanism (with the subprocess $gg\to B_{cJ,L=1}^*+\bar{c}+b$ being dominated) into account as that for $S$-wave. In order to make the addendum piece of the upgraded generator as compact as possible so as to increase its efficiency, we manipulate the amplitude as compact as possible with FDC (a software for generating Feynman diagrams and the algebra amplitudes, and for manipulating algebra formulae analytically etc) and certain simplification techniques. The correctness of the program is tested by checking the gauge invariance of the amplitude and by comparing the numerical results with the existent ones in the literature carefully.Comment: 21 page, 4 figure

Dynamical Complexity, Intermittent Turbulence, Coarse-Grained Dissipation, Criticality and Multifractal Processes

The ideas of dynamical complexity induced intermittent turbulence by sporadic localized interactions of coherent structures are discussed. In particular, we address the phenomenon of magnetic reconfiguration due to coarse-grained dissipation as well as the interwoven connection between criticality and multifractal processes. Specific examples are provided.Comment: 6 pages, 2 figures, submitted to AIP Conference Proceedings for the 6th Annual International Astrophysics Conference, Honolulu, March 16-22, 200

Achievable Angles Between two Compressed Sparse Vectors Under Norm/Distance Constraints Imposed by the Restricted Isometry Property: A Plane Geometry Approach

The angle between two compressed sparse vectors subject to the norm/distance constraints imposed by the restricted isometry property (RIP) of the sensing matrix plays a crucial role in the studies of many compressive sensing (CS) problems. Assuming that (i) u and v are two sparse vectors separated by an angle thetha, and (ii) the sensing matrix Phi satisfies RIP, this paper is aimed at analytically characterizing the achievable angles between Phi*u and Phi*v. Motivated by geometric interpretations of RIP and with the aid of the well-known law of cosines, we propose a plane geometry based formulation for the study of the considered problem. It is shown that all the RIP-induced norm/distance constraints on Phi*u and Phi*v can be jointly depicted via a simple geometric diagram in the two-dimensional plane. This allows for a joint analysis of all the considered algebraic constraints from a geometric perspective. By conducting plane geometry analyses based on the constructed diagram, closed-form formulae for the maximal and minimal achievable angles are derived. Computer simulations confirm that the proposed solution is tighter than an existing algebraic-based estimate derived using the polarization identity. The obtained results are used to derive a tighter restricted isometry constant of structured sensing matrices of a certain kind, to wit, those in the form of a product of an orthogonal projection matrix and a random sensing matrix. Follow-up applications to three CS problems, namely, compressed-domain interference cancellation, RIP-based analysis of the orthogonal matching pursuit algorithm, and the study of democratic nature of random sensing matrices are investigated.Comment: submitted to IEEE Trans. Information Theor