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تسجيل مستخدم جديدD-brane instanton induced mu-terms and their hierarchical structure
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We study the mu-term matrix of Higgs pairs induced by the D-brane instanton effects in intersecting D6-brane models compactified on T6. It is found that the mu-term matrix has a certain permutation symmetry and its eigenvalues have large hierarchical structure without fine tuning.
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