4,816 research outputs found
Hidden Higgs Particle
A modification of the standard model of electroweak interactions with the
nonlocal Higgs sector is proposed. Proper form of nonlocality makes Higgs
particles unobservable after the electroweak symmetry breaking. They appear
only as a virtual state because their propagator is an entire function. We
discuss some specific consequences of this approach comparing it with the
conventional standard model.Comment: 15 pages, LaTeX, no figure
Lepton number, black hole entropy and 10 to the 32 copies of the Standard Model
Lepton number violating processes are a typical problem in theories with a
low quantum gravity scale. In this paper we examine lepton number violation
(LNV) in theories with a saturated black hole bound on a large number of
species. Such theories have been advocated recently as a possible solution to
the hierarchy problem and an explanation of the smallness of neutrino masses.
Naively one would expect black holes to introduce TeV scale LNV operators, thus
generating unacceptably large rates of LNV processes. We show, however, that
this does not happen in this scenario due to a complicated compensation
mechanism between contributions of different Majorana neutrino states to these
processes. As a result rates of LNV processes are extremely small and far
beyond experimental reach, at least for the left-handed neutrino states.Comment: 6 pages, 3 figures, to appear in Proc. PASCOS 2010, Valencia, Spai
Leptoquarks: Neutrino masses and accelerator phenomenology
Leptoquark-Higgs interactions induce mixing between leptoquark states with
different chiralities once the electro-weak symmetry is broken. In such LQ
models Majorana neutrino masses are generated at 1-loop order. Here we
calculate the neutrino mass matrix and explore the constraints on the parameter
space enforced by the assumption that LQ-loops explain current neutrino
oscillation data. LQs will be produced at the LHC, if their masses are at or
below the TeV scale. Since the fermionic decays of LQs are governed by the same
Yukawa couplings, which are responsible for the non-trivial neutrino mass
matrix, several decay branching ratios of LQ states can be predicted from
measured neutrino data. Especially interesting is that large lepton flavour
violating rates in muon and tau final states are expected. In addition, the
model predicts that, if kinematically possible, heavier LQs decay into lighter
ones plus either a standard model Higgs boson or a gauge boson.
Thus, experiments at the LHC might be able to exclude the LQ mechanism as
explanation of neutrino data.Comment: 28 pages, 10 figure
On Prospects for Exploration of Supersymmetry in Double Beta Decay Experiments
We analyze constraints on the parameters of the R-parity violating
supersymmetry which can be extracted from non-observation of the neutrinoless
nuclear double beta decay () at a given half-life lower bound.
Our analysis covers a large class of phenomenologically viable R-parity
violating SUSY models. We introduce special characteristics: the SUSY
sensitivity of a decaying isotope and the SUSY reach of a
experiment. The former provides a physical criterion for a
selection of the most promising isotopes for SUSY searches and the latter gives
a measure of success for a experiment in exploring the
R-parity violating SUSY parameter space. On this basis we discuss prospects for
exploration of supersymmetry in various experiments.Comment: 11 pages, 5 Postscript figures. Modified and updated version is
printed also in Proc. of NANP97 (JINR, Dubna, July 7--11, 1997): Phys. Atom
Nucl, 1998, 61, vol. 6, p.1092--109
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