3,670 research outputs found
A Reference Model for Anomalously Interacting Bosons
A simple reference model for anomalously interacting bosons is proposed and
implemented in the CompHEP package. This allows preparing for an experimental
search of these bosons at powerful colliders, such as Tevatron and LHC. New
signatures and some experimental consequences are shortly considered.Comment: updated version with new D0 data, to be published in Physics of
Particles and Nuclei Letters, 2011, Vol. 8, No.
Chizhov and Petcov Reply
We have found in [1] new conditions for a total neutrino conversion in the
case of neutrino oscillations taking place in a medium, consisting of n = 2 (or
3) alternating layers with constant densities and . It is claimed in
[4] that our results are particular case of enhancement of neutrino
oscillations, which was suggested earlier by other authors and was widely
discussed in the literature. We refute these claims, confirming the novelty of
our results.Comment: 2 pages, LATEX; concise (essentially 1 page) and somewhat modified
version of Ref. SISSA 5/2000/EP (hep-ph/0003110); reply on the ``Comment on
New Conditions for a Total Neutrino Conversion in a Medium'', Phys. Rev.
Lett. 85 (2000) 3978; published as ``Chizhov and Petcov Reply'' in Phys. Rev.
Lett. 85 (2000) 397
Sensitivity to new physics: a_e vs. a_mu
At present it is generally believed that ``new physics'' effects contribute
to leptonic anomalous magnetic moment, a_l, via quantum loops only and they are
proportional to the squared lepton mass, (m_l)^2. An alternative mechanism for
a contribution by new physics is proposed. It occurs at the tree level and
exhibits a linear rather than quadratic dependence on m_l. This leads to a much
larger sensitivity of a_e to the new physics than was expected so far.Comment: 4 pages, 2 figure
Utilization of the wastes of vital activity
The recycling of wastes from the biological complex for use in life-support systems is discussed. Topics include laboratory equipment, heat treatment of waste materials, mineralization of waste products, methods for production of ammonium hydroxide and nitric acid, the extraction of sodium chloride from mineralized products, and the recovery of nutrient substances for plants from urine
Towards a Geometric Approach to the Formulation of the Standard Model
A geometric interpretation of the spontaneous symmetry breaking effect, which
plays a key role in the Standard Model, is developed. The advocated approach is
related to the effective use of the momentum 4-spaces of the constant
curvature, de Sitter and anti de Sitter, in the apparatus of quantum field
theory.Comment: 8 pages, LaTe
Anomalously interacting new extra vector bosons and their first LHC constraints
In this review phenomenological consequences of the Standard Model extension
by means of new spin-1 chiral fields with the internal quantum numbers of the
electroweak Higgs doublets are summarized. The prospects for resonance
production and detection of the chiral vector and bosons at
the LHC energies are considered. The boson can be observed as a
Breit-Wigner resonance peak in the invariant dilepton mass distributions in the
same way as the well-known extra gauge bosons. However, the bosons
have unique signatures in transverse momentum, angular and pseudorapidity
distributions of the final leptons, which allow one to distinguish them from
other heavy neutral resonances. In 2010, with 40 pb of the LHC
proton-proton data at the energy 7 TeV, the ATLAS detector was used to search
for narrow resonances in the invariant mass spectrum of and
final states and high-mass charged states decaying to a charged
lepton and a neutrino. No statistically significant excess above the Standard
Model expectation was observed. The exclusion mass limits of 1.15 TeV and
1.35 TeV were obtained for the chiral neutral and charged
bosons, respectively. These are the first direct limits on the and
boson production. For almost all currently considered exotic models the
relevant signal is expected in the central dijet rapidity region. On the
contrary, the chiral bosons do not contribute to this region but produce an
excess of dijet events far away from it. For these bosons the appropriate
kinematic restrictions lead to a dip in the centrality ratio distribution over
the dijet invariant mass instead of a bump expected in the most exotic models.Comment: 24 pages, 34 figure, based on talk given by V.A.Bednyakov at 15th
Lomonosov conference, 22.08.201
A Review of Rare Pion and Muon Decays
After a decade of no measurements of pion and muon rare decays, PIBETA, a new
experimental program is producing its first results. We report on a new
experimental study of the pion beta decay, Pi(+) -> Pi(0) e(+) Nu, the Pi(e2
gamma) radiative decay, Pi(+) -> e(+) Nu Gamma, and muon radiative decay, Mu ->
e Nu Gamma. The new results represent four- to six-fold improvements in
precision over the previous measurements. Excellent agreement with Standard
Model predictions is observed in all channels except for one kinematic region
of the Pi(e2 gamma) radiative decay involving energetic photons and
lower-energy positrons.Comment: 10 pages, 6 figures, 2 tables, invited talk presented at MESON 2004,
8th Int'l. Workshop on Meson Production, Properties and Interaction, Krakow,
Poland 4-8 June 200
Vector meson couplings to vector and tensor currents in extended NJL quark model
A simple explanation of the dynamic properties of vector mesons is given in
the framework of extended Nambu - Jona-Lasinio quark model. New mass relations
among the hadron vector resonances are derived. The results of this approach
are in good accordance with the QCD sum rules, the lattice calculations and the
experimental data.Comment: 4 pages, 2 figure
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