2,433 research outputs found
A linear moose model with pairs of degenerate gauge boson triplets
The possibility of the existence of a strongly interacting electroweak
symmetry breaking sector, as opposed to the weakly interacting light Higgs of
the Standard Model, is not yet ruled out by experiments. In this paper we make
an extensive study of a deconstructed model (or ``moose'' model) providing a
possible effective description of such a strong symmetry breaking sector, and
show its compatibility with experimental data for a wide portion of the model
parameters space. The model is a direct generalization of the previously
proposed D-BESS model.Comment: Latex file, 17 pages, 2 figures, published versio
The Invisible Higgs Decay Width in the Add Model at the LHC
Assuming flat universal extra dimensions, we demonstrate that for a light
Higgs boson the process will be observable at the level at the LHC for the
portion of the Higgs-graviscalar mixing () and effective Planck mass
() parameter space where channels relying on visible Higgs decays fail to
achieve a signal. Further, we show that even for very modest values
of the invisible decay signal probes to higher than does the
(-independent) jets/\gam + missing energy signal from graviton
radiation. We also discuss various effects, such as Higgs decay to two
graviscalars, that could become important when is of order 1.Comment: 6 pages, 2 figures, To appear in the Proceedings of the Les Houches
Workshop 2003: ``Physics at TeV Colliders'', ed. F. Boudjem
Limits and Criticalities of Predictions and Forecasting in Complex Social and Economic Scenarios: A Cybernetics Key
Predictions play a key role in assuring the status of ârationalityâ in
decisions. Nevertheless, in the ïŹeld of social sciences and economics, predictions
fail to correctly depict the oncoming scenarios. Why is it so difïŹcult to achieve
quantitative prediction of social and economic systems? Can science provide reliable
predictions of social and economic paths that can be used to implement
effective interventions? As in the notorious âEl Farol bar problemâ depicted by
Brian Arthur (Am Econ Rev 84:406â411, 1994), the validity of predictive models is
more a social issue than a matter of good mathematics. Predictability in social
systems is due to limited knowledge of society and human behavior. We do not yet
have worldwide, quantitative knowledge of human social behavior; for instance, the
perception of certain issues or the predisposition to adopt certain behaviors. Though
tremendous progress has been made in recent years in data gathering thanks to the
development of new technologies and the consequent increase in computational
power, social and economic models still rely on assumptions of rationality that
undermine their predictive effectiveness. Through some theoretical and epistemological
reïŹections, we propose a way in which the cybernetic paradigm of complexity
management can be used for better decision-making in complex scenarios
with a comprising, dynamic, and evolving approach. We will show how a cybernetic
approach can help to overcome the fear of uncertainty and serve as an
effective tool for improving decisions and actions
University Incubator as Catalyst of Resources for Academic Spin-Offs. The Case of ARCA Consortium
Today we can observe an increasing proliferation of new academic spin-off initiatives aimed to transfer knowledge from the university to the market. Due to their strategic role in enhancing the development of technological innovation, academic spin-offs can attain high levels of social performance and consonance with their environment. At the same time, they must overcome many difficulties if they are to achieve a high level of financial performance and growth. They are often considered to be mere vehicles for the transmission
of knowledge, implying that their entrepreneurial potential is not fully exploited. According to the Resource
Based View (RBV) the competitive disadvantage of an academic spin-off is due to a lack of resources. This
paper will join this stream of research in order to analyze the financial performance of academic spin-offs. We
examine the case of Arca Consortiumâs incubator, established by the University of Palermo, and of the academic spin-offs it has supported and continues to assist. The empirical analysis, based on two linear regression models, is performed based on 19 case studies of spin-offs created between 2007 and 2009 by academicians of the University of Palerm
The Drivers of Customer Satisfaction in the Hospitality Industry. Applying the Kano Model to Sicilian Hotels
Starting from the assessment that hotels need to embrace a managerial approach oriented towards customer satisfaction, we adopt the Kano model to identify the relevant drivers of satisfaction of hotels guest in the main cities of Sicily, Italy. This study analyzes the customer satisfaction requirements for Sicilian hotels in order to suggest and weigh a set of key attributes that hotel managers need to consider in order to create an attractive offer. We base our analysis on the qualitative data collected through 600 questionnaires submitted to hotel guests of twenty Sicilian three-star hotels located in city downtowns, in different provinces and locations
Evidence of microbial activity from a shallow water whale fall (Voghera, northern Italy)
The fossil bones, associated carbonate cements and enclosing concretion of a Miocene mysticete from inner shelf deposits (Monte Vallassa Formation, northern Italy) were analyzed for evidence of microbial activity. Optical and scanning electron microscopy, Raman spectroscopy, and stable C and O isotope geochemistry were used for high spatial resolution microfacies and biosedimentological analyses. Whale cancellous bones were filled by different carbonate cements including microcrystalline dolomite, rhombohedral dolomite and sparry calcite. Biofabric and biominerals such as microbial peloids, clotted textures and pyrite framboids were associated with the dolomite cements. Dolomite inside cancellous bones and in the enclosing concretion showed similar isotopic values (avg ÎŽ 13C: -7.12â°; avg ÎŽ 18O: +3.81â°), depleted with respect to the (late) sparry calcite cement (avg ÎŽ 13C: -0.55â°; avg ÎŽ 18O: -0.98â°). Microcrystalline barite (BaSO 4) was observed on the external surface of the bones. In addition, two different types of microborings were recognized, distinguished by their size and morphology and were ascribed respectively to prokaryote and fungal trace makers. Our results testify for the development of a diverse microbial ecosystem during the decay of a shallow water whale carcass, which could be detected in the fossil record. However, none of the observed biosignatures (e.g., microbial peloids, clotted textures) can be used alone as a positive fossil evidence of the general development of a sulfophilic stage of whale fall ecological succession. The occurrence of the hard parts of chemosynthetic invertebrates associated with fossil whale bones is still the more convincing proof of the development of a sulfide-base chemoautotrophic ecosystem. © 2011 Elsevier B.V
Saving the fourth generation Higgs with radion mixing
We study Higgs-radion mixing in a warped extra dimensional model with
Standard Model fields in the bulk, and we include a fourth generation of chiral
fermions. The main problem with the fourth generation is that, in the absence
of Higgs-radion mixing, it produces a large enhancement in the Higgs production
cross-section, now severely constrained by LHC data. We analyze the production
and decay rates of the two physical states emerging from the mixing and
confront them with present LHC data. We show that the current signals observed
can be compatible with the presence of one, or both, of these Higgs-radion
mixed states (the and the ), although with a severely restricted
parameter space. In particular, the radion interaction scale must be quite low,
Lambda_\phi ~ 1-1.3 TeV. If m_\phi ~ 125 GeV, the state must be heavier
(m_h>320 GeV). If m_h ~ 125 GeV, the state must be quite light or close
in mass (m_\phi ~ 120 GeV). We also present the modified decay branching ratios
of the mixed Higgs-radion states, including flavor violating decays into fourth
generation quarks and leptons. The windows of allowed parameter space obtained
are very sensitive to the increased precision of upcoming LHC data. During the
present year, a clear picture of this scenario will emerge, either confirming
or further severely constraining this scenario.Comment: 22 pages, 5 figures, 4 table
Analysis of Narrow s-channel Resonances at Lepton Colliders
The procedures for studying a single narrow s-channel resonance or nearly
degenerate resonances at a lepton collider, especially a muon collider, are
discussed. In particular, we examine four methods for determining the
parameters of a narrow s-channel resonance: scanning the resonance, measuring
the convoluted cross section, measuring the Breit-Wigner area, and sitting on
the resonance while varying the beam energy resolution. This latter procedure
is new and appears to be potentially very powerful. Our focus is on computing
the errors in resonance parameters resulting from uncertainty in the beam
energy spread. Means for minimizing these errors are discussed. The discussion
is applied to the examples of a light SM-Higgs, of the lightest pseudogoldstone
boson of strong electroweak breaking, and of the two spin-1 resonances of the
Degenerate BESS model (assuming that the beam energy spread is less than their
mass splitting). We also examine the most effective procedures for nearly
degenerate resonances, and apply these to the case of Degenerate BESS
resonances with mass splitting of order the beam energy spread.Comment: 63 pages, 16 figure
A Strong Electroweak Sector at Future mu^+ mu^- Colliders
We discuss the prospects for detecting at a muon collider the massive new
vector resonances V and light pseudo-Nambu-Goldstone bosons P of a typical
strongly interacting electroweak sector (as represented by the BESS model).
Expected sensitivities to V's at a high energy collider are evaluated and the
excellent prospects for discovering P's via scanning at a low energy collider
are delineated.Comment: LaTeX, uses aipproc.cls, aipproc.sty, 10 pages, 6 figures, presented
at the Workshop on Physics at the First Muon Collider, Fermilab, November
1997, to appear in the Proceedings, some references added and minor changes
in the tex
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