665 research outputs found
A More Flavored Higgs boson in Supersymmetric models
A More flavored Higgs boson arises when the flavor structure encoded in SUSY
extensions of the SM is transmited to the Higgs sector. The flavor-Higgs
transmition mechanism can have a radiative or mixing origin, as it is
illustrated with several examples, and can produce interesting Higgs signatures
that can be probed at future high-energy colliders. Within the MSSM, the flavor
mediation mechanism can be of radiative type, as it is realized trhough
gaugino-slepton loops, which transmit the flavor structture of the
soft-breaking sector to the Higgs bosons. In particular we focus on evaluating
the contributions from the general trilinear terms to the lepton flavor
violating Higgs (LFV) vertices. On the other hand, as an example of flavor
mediation through mixing, we discuss an E_6 inspired multi-Higgs model, with an
abelian flavor symmetry, where LFV as well as lepton flavor conserving Higgs
effects are found to arise, though in this case at tree-level. We find that
Tevatron and LHC can provide information on the flavor structure of these
models through the detection of the LFV higgs mode h-> tau+mu, while NLC can
perform high-precision measurements of the LFC mode h-> tau tau.Comment: 17 pages, 5 tables, 3 figures; corrected mistake in last section,
results changed but conclusions remmai
Lepton Flavour Violating Heavy Higgs Decays Within the nuMSSM and Their Detection at the LHC
Within the MSSM, a Minimal Supersymmetric neutrino See-saw Model, Lepton
Flavour Violating Higgs couplings are strongly enhanced at large
(\gsim30), which can lead to BR, for
M_{H^0/A^0}\gsim 160 GeV. Enhancements on the production of Higgs bosons,
through the gluon fusion mechanism, , and the associated
production channel , whose rates grow with
, as well as the mass degeneracy that occurs between the and
states in this regime, also contribute to further the possibilities to
detect a heavy Higgs signal into pairs. We show that the separation
of Higgs events from the background at the upcoming CERN Large Hadron
Collider could be done for Higgs masses up to about 600 GeV for 300 fb
of luminosity, for large values. However, even with as little as 10
fb one can probe masses up to 400 GeV or so, if
. Altogether, these processes then provide a new Higgs discovery
mode as well as an independent test of flavour physics.Comment: 13 pages, 5 figure
Mass matrix Ansatz and lepton flavor violation in the THDM-III
Predictive Higgs-fermion couplings can be obtained when a specific texture
for the fermion mass matrices is included in the general two-Higgs doublet
model. We derive the form of these couplings in the charged lepton sector using
a Hermitian mass matrix Ansatz with four-texture zeros. The presence of
unconstrained phases in the vertices phi-li-lj modifies the pattern of
flavor-violating Higgs interactions. Bounds on the model parameters are
obtained from present limits on rare lepton flavor violating processes, which
could be extended further by the search for the decay tau -> mu mu mu and mu-e
conversion at future experiments. The signal from Higgs boson decays phi -> tau
mu could be searched at the large hadron collider (LHC), while e-mu transitions
could produce a detectable signal at a future e mu-collider, through the
reaction e mu -> h0 -> tau tau.Comment: 17 pages, 9 figure
H^+ -> W^+ l_i^- l_j^+$ decay in the two Higgs doublet model
We study the lepton flavor violating H^+ -> W^+ l_i^- l_j^+ and the lepton
flavor conserving $H^+ -> W^+ l_i^- l_i^+ (l_i=\tau, l_j=\mu) decays in the
general 2HDM, so called model III. We estimate the decay width \Gamma for LFV
(LFC) at the order of the magnitude of (10^{-11}-10^{-5}) GeV
((10^{-9}-10^{-4}) GeV), for 200 GeV\leq m_{H^\pm}\leq 400
GeV, and the intermediate values of the coupling
\bar{\xi}^{E}_{N,\tau \mu}\sim 5 GeV (\bar{\xi}^{E}_{N,\tau
\tau}\sim 30 GeV). We observe that the experimental result of the process
under consideration can give comprehensive information about the physics beyond
the standard model and the existing free parameters.Comment: 8 pages, 7 Figure
Search strategies for pair production of heavy Higgs bosons decaying invisibly at the LHC
The search for heavy Higgs bosons at the LHC represents an intense experimental program, carried out by the ATLAS and CMS collaborations, which includes the hunt for invisible Higgs decays and dark matter candidates. No significant deviations from the SM backgrounds have been observed in any of these searches, imposing significant constraints on the parameter space of different new physics models with an extended Higgs sector. Here we discuss an alternative search strategy for heavy Higgs bosons decaying invisibly at the LHC, focusing on the pair production of a heavy scalar H together with a pseudoscalar A, through the production mode qqÂŻâZââHA. We identify as the most promising signal the final state made up of 4b+ET miss, coming from the heavy scalar decay mode HâhhâbbÂŻbbÂŻ with h being the discovered SM-like Higgs boson with mh=125GeV, together with the invisible channel of the pseudoscalar. We work within the context of simplified MSSM scenarios that contain quite heavy sfermions of most types with O(10)TeV masses, while the stops are heavy enough to reproduce the 125 GeV mass for the lightest SM-like Higgs boson. By contrast, the gauginos/higgsinos and the heavy MSSM Higgs bosons have masses near the EW scale. Our search strategies, for a LHC center-of-mass energy of s=14TeV, allow us to obtain statistical significances of the signal over the SM backgrounds with values up to âŒ1.6Ï and âŒ3Ï for total integrated luminosities of 300fbâ1 and 1000fbâ1, respectively.Fil: Arganda, E.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; ArgentinaFil: Diaz-Cruz, J.L.. BenemĂ©rita Universidad AutĂłnoma de Puebla; MĂ©xicoFil: Mileo, N.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; ArgentinaFil: Morales, R.A.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; ArgentinaFil: Szynkman, A.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; Argentin
New Higgs signals induced by mirror fermion mixing effects
We study the conditions under which flavor violation arises in scalar-fermion
interactions, as a result of the mixing phenomena between the standard model
and exotic fermions. Phenomenological consequences are discussed within the
specific context of a left-right model where these additional fermions have
mirror properties under the new SU(2)_R gauge group.
Bounds on the parameters of the model are obtained from LFV processes; these
results are then used to study the LFV Higgs decays (H --> tau l_j, l_j = e,
mu), which reach branching ratios that could be detected at future colliders.Comment: 12 pages, 2 figures, ReVTex4, graphicx, to be published in Phys. Rev.
A Window on the CP-violating Phases of MSSM from Lepton Flavor Violating Processes
It has recently been shown that by measuring the transverse polarization of
the final particles in the LFV processes , and
, one can derive information on the CP-violating phases of the
underlying theory. We derive formulas for the transverse polarization of the
final particles in terms of the couplings of the effective potential leading to
these processes. We then study the dependence of the polarizations of and
in the and on the parameters of the
Minimal Supersymmetric Standard Model (MSSM). We show that combining the
information on various observables in the and
search experiments with the information on the electric dipole moment of the
electron can help us to solve the degeneracies in parameter space and to
determine the values of certain phases.Comment: 16 pages, 8 figure
Radiative Mechanism to Light Fermion Masses in the MSSM
In a previous work we have showed that the Symmetry,
imply that the light fermions, the electron and the quarks, and , get
their masses only at one loop level. Here, we considere the more general
hypothesis for flavour mixing in the sfermion sector in the MSSM. Then, we
present our results to the masses of these light fermions and as a final result
we can explain why the quark is heavier than the quarks. This
mechanism is in agrement with the experimental constraint on the sfermion's
masses values.Comment: 22 pages, 8 figures, TeX mistakes corrected, accepted for publication
in JHE
Limits on excited tau leptons masses from leptonic tau decays
We study the effects induced by excited leptons on the leptonic tau decay at
one loop level. Using a general effective lagrangian approach to describe the
couplings of the excited leptons, we compute their contributions to the
leptonic decays and use the current experimental values of the branching ratios
to put limits on the mass of excited states and the substructure scale.Comment: 10 pages, 6 figures, to be published in Phys. Rev.
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