746 research outputs found
Higgs revised in Supersymmetric Economical 3-3-1 model with B/\mu-type terms
We re-investigate the scalar potential and the Higgs sector of the
supersymmetric economical 3-3-1 model (SUSYE331) in the presence of the B/\mu
type terms which has many important consequences. First, the model contains no
massless Higgs fields. Second, we prove that the soft mass parameters of
Higgses must be at the SU(3)_L scale. As a result, the masses of the Higgses
drift toward this scale except one light real neutral Higgs with the mass of
m_Z|cos(2\gamma)| at the tree level. We also show that there are some Higgses
containing many properties of the Higgses in the minimal supersymmetric
standard model (MSSM), especially in the neutral Higgs sector. One exact
relation in the MSSM, m^2_H^{+/-}=m^2_A+m^2_W, is still true in the SUSYE331.
Based on this result we make some comments on the lepton flavor violating
decays of these Higgses as one of signatures of new physics in the SUSYE331
model which may be detected by present colliders.Comment: Matches version accepted for publication in EPJC. Typos are
corrected. We add a new section, a new appendix, a new figure and new
references to explain more clearly the properties of the lightest neutral
Higgs. Results unchange
Symmetry Factors of Feynman Diagrams for Scalar Fields
The symmetry factor of Feynman diagrams for real and complex scalar fields is
presented. Being analysis of Wick expansion for Green functions, the mentioned
factor is derived in a general form. The symmetry factor can be separated into
two ones corresponding to that of connected and vacuum diagrams. The
determination of symmetry factors for the vacuum diagrams is necessary as they
play a role in the effective action and phase transitions in cosmology. In the
complex scalar theory the diagrams different in topology may give the same
contribution, hence inverse of the symmetry factor (1/S) for total contribution
is a summation of each similar ones (1/S_i), i.e., 1/S = \sum_i (1/S_i).Comment: Journal version, new references adde
Theory of Luminescent Emission in Nanocrystal ZnS:Mn with an Extra Electron
We consider the effect of an extra electron injected into a doped quantum dot
. The Coulomb interaction and the exchange interaction between the
extra electron and the states of the Mn ion will mix the wavefunctions, split
the impurity energy levels, break the previous selection rules and change the
transition probabilities. Using this model of an extra electron in the doped
quantum dot, we calculated the energy and the wavefunctions, the luminescence
probability and the transition lifetime and compare with the experiments. Our
calculation shows that two orders of magnitudes of lifetime shortening can
occur in the transition when an extra electron is present.Comment: 15 pages, 2 Figs No change in Fig
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