458 research outputs found
Excluding a small minor
There are sixteen 3-connected graphs on eleven or fewer edges. For each of these graphs H we discuss the structure of graphs that do not contain a minor isomorphic to H. © 2012 Elsevier B.V. All rights reserved
A chain theorem for 3 \u3csup\u3e+\u3c/sup\u3e-connected graphs
A 3-connected graph is called 3 +-connected if it has no 3-separation that separates a large fan or K 3,n from the rest of the graph. It is proved in this paper that except for K 4, every 3 +-connected graph has a 3 +-connected proper minor that is at most two edges away from the original graph. This result is used to characterize Q-minor-free graphs, where Q is obtained from the cube by contracting an edge. © 2012 Society for Industrial and Applied Mathematics
Lepton-Flavor Violating Processes in Topcolor Assisted Technicolor Models
We consider the lepton-flavor violating(LFV) processes
in the framework of topcolor assisted technicolor(TC2) models. We find that the
new gauge boson predicted by TC2 models can give significantly
contributions to these processes via the flavor changing couplings. The present
experimental bound on the LFV process gives severe
constraints on the TC2 models. In the case that the mass
is consistent with other experimental constraints, we obtain constraints on the
lepton mixing factors and . The future LFV
experiments will be probe of the TC2 models.Comment: some mistakes corrected and several references adde
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