SSC Result 2017 All Education Board

SSC Result 2017 Bangladesh published on 30 may 2017. The official website of Bangladesh Education Board will be published SSC Result 2017 Educational Website in Bangladesh. Here uou get SSC Result 2017 Dhaka Board ,SSC Result 2017 Barisal Board ,SSC Result 2017 Rajshahi Board ,SSC Result 2017 Chittagong Board ,SSC Result 2017 Jessore Board ,SSC Result 2017 Sylhet Board ,SSC Result 2017 Dinajpur Board ,SSC Result 2017 Dakhil Board ,SSC Result 2017 Vocational Board & SSC Exam routine 2017 etc

Dynamical effects of QCD in q2qˉ2q^2 \bar{q}^{2} systems

We study the coupling of a tetraquark system to an exchanged meson-meson channel, using a pure gluonic theory based four-quark potential {\em matrix} model which is known to fit well a large number of data points for lattice simulations of different geometries of a four-quark system. We find that if this minimal-area-based potential matrix replaces the earlier used simple Gaussian form for the gluon field overlap factor $f$ in its off-diagonal terms, the resulting $T$-matrix and phase shifts develop an angle dependence whose partial wave analysis reveals $D$ wave and higher angular momentum components in it. In addition to the obvious implications of this result for the meson-meson scattering, this new feature indicates the possibility of orbital excitations influencing properties of meson-meson molecules through a polarization potential. We have used a formalism of the resonating group method, treated kinetic energy and overlap matrices on model of the potential matrix, but decoupled the resulting complicated integral equations through the Born approximation. In this exploratory study we have used a quadratic confinement and not included the spin-dependence; we also used the approximation of equal constituent quark masses.Comment: 18 pages, 9 figure

Application of multiple criteria decision methods in space exploration initiative design and planning

Fellowship activities were directed towards the identification of opportunities for application of the Multiple Criteria Decision Making (MCDM) techniques in the Space Exploration Initiative (SEI) domain. I identified several application possibilities and proposed demonstration application in these three areas: evaluation and ranking of SEI architectures, space mission planning and selection, and space system design. Here, only the first problem is discussed. The most meaningful result of the analysis is the wide separation between the two top ranked architectures, indicating a significant preference difference between them. It must also be noted that the final ranking reflects, to some extent, the biases of the evaluators and their understanding of the architecture

Effect of the Quark-Gluon Vertex on Dynamical Chiral Symmetry Breaking

In this work we investigate how the details of the quark-gluon interaction vertex affect the quantitative description of chiral symmetry breaking and dynamical mass generation through the gap equation. We employ the Maris-Tandy (MT) and Qin-Chang (QC) models for the gluon propagator and the effective strong running coupling. The gap equation is solved by employing several vertex Ans${\rm \ddot{a}}$tze which have been constructed in order to implement some of the key aspects of a gauge field theory such as gauge invariance and multiplicative renormalizability. We find that within a small variation of MT and QC model parameters, all truncations point towards the same quantitative pattern of chiral symmetry breaking, the running quark mass function, ensuring the robustness of this approach.Comment: 12 page