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Rare Meson Decays in Theories Beyond the Standard Model. A. Ali (DESY), A. V. Borisov, M. V. Sidorova (MSU). SM. Beyond the SM:. Massive Majorana neutrinos R-parity-violating SUSY. Feynman diagrams for the rare meson decay mediated by Majorana neutrinos. tree. box.
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Rare Meson Decays in Theories Beyondthe Standard Model A. Ali (DESY), A. V. Borisov, M. V. Sidorova (MSU) 2-nd Vienna Central European Seminar, Nov 25-27, 2005
SM Beyond the SM: • Massive Majorana neutrinos • R-parity-violating SUSY 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Feynman diagrams for the rare meson decay mediated by Majorana neutrinos tree box 2-nd Vienna Central European Seminar, Nov 25-27, 2005
1. Rare Meson Decays mediated by massive Majorana neutrinos The width of the decay: - tree diagram - box diagram - lepton tensor - hadron tensor 2-nd Vienna Central European Seminar, Nov 25-27, 2005
LEPTON TENSOR - neutrino mixing matrix - the relative CP-phases, 2-nd Vienna Central European Seminar, Nov 25-27, 2005
HADRONTENSOR 2-nd Vienna Central European Seminar, Nov 25-27, 2005
The Bethe-Salpeter Formalism Mesons as bound states of a quark and an antiquark: - the center-of-mass - the relative coordinates - color index 2-nd Vienna Central European Seminar, Nov 25-27, 2005
- -group factor • the mass of the meson M - quark masses - the relative 4-momentum - the total 4-momentum of the meson 2-nd Vienna Central European Seminar, Nov 25-27, 2005
- model dependent scalarfunction - parameter of the model The definition of the decay constant of the meson: 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Amplitude for tree and box diagrams of the meson decay 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Heavy neutrinos In this case the total decay width is model independent - the effective inverse Majorana mass 2-nd Vienna Central European Seminar, Nov 25-27, 2005
The branching ratios Using bounds on matrix elements from the othersprocesses one can obtain indirect bounds on the branching ratios. The bound from of nucleus: Also there are bounds on other mixing parameters: 2-nd Vienna Central European Seminar, Nov 25-27, 2005
From the heavy neutral Majorana lepton detecting experiments: Assuming one heavy neutrino scenario: 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Experimental and indirect bounds on the branching ratios for the rare meson decays mediated by heavy Majorana neutrinos Ind. Bounds on Rare decay 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Light neutrinos t-amplitudeis model independent b-amplitude is model dependent - the effective Majorana mass 2-nd Vienna Central European Seminar, Nov 25-27, 2005
- 1-dimensional integral The numerical calculations of multidimensional phase integ- rals were carried out using the program VEGAS based on Monte-Carlo mechanism. - 6-dimensional integral - 5-dimensional integral 2-nd Vienna Central European Seminar, Nov 25-27, 2005
The bound from: From cosmological data and neutrino oscillation experiments, assuming the existence of 3 light massive neutrino the constraint Taking into account Using the best fit of mixing matrix from neutrino oscillation experiments 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Contribution of tree, box diagrams, their interference and indirect bounds on the branching ratios for the rare meson decays mediated by light Majorana neutrinos Ind. Bounds on 2-nd Vienna Central European Seminar, Nov 25-27, 2005
2. Rare Meson Decays in R-parity-violating SUSY Theories R-parity is a discrete, multiplicative symmetrydefined as S, B, L – spin, barion and lepton quantum numbers The SM fields, including additional Higgs boson fields appearing in the extended gauge models, have Rp=+1 while their superpartners have Rp=-1. This symmetry has been imposed on the minimal supersymmetric SM to ensure B and L number conservation. However, SUSY doesn’t require Rp conservation. The most general gauge invariant form of the superpotential in minimal SUSY SM is 2-nd Vienna Central European Seminar, Nov 25-27, 2005
L B - generation indices; are lepton andquark doublet superfields and arelepton and up, down quark singlet superfields. All arethe coupling constants. MSSM Rp An alternative discrete symmetry with the same physical result, for example: proton stability 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Lagrangian, that yields contributions to the decay The lepton number violating part of the Lagrangian has the form: 2-nd Vienna Central European Seminar, Nov 25-27, 2005
The Lagrangian terms corresponding to gluino and neutralino interactions with fermionsandtheir superpartners are , , Here are 3x3 Gell-Mann matrices. - neutralino coupling constants. Here and are the electric charge and weak isospin of the field . 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Feynman diagrams for the rare meson decay in SUSY model tree box 3 2-nd Vienna Central European Seminar, Nov 25-27, 2005
- the 4-momentum of the initial and finalmesons 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Using the input parameters for mesons: values of neutralino mixing matrix elements (hep-ph/0311123): Bounds on RPV couplings and the masses of the various superpartners to be comparable the SUSY mass scale Wefound that these R-parity violating contributionscould be muchlarger then those from massive neutrinos. 2-nd Vienna Central European Seminar, Nov 25-27, 2005
Bounds on the branching ratios for the rare meson decays in SUSY theories with R-parity non-conservation. Rare decay 2-nd Vienna Central European Seminar, Nov 25-27, 2005