192 research outputs found
Project finance recent applications and future trends: the state of the art
This paper provides a review of the state of the art of project finance methodology. The growing body of literature in this field serves to emphasize the increasing use and new areas of application of project finance techniques. The paper attempts to describe the main features of project finance, to explain the role of the participants, and the main contractual arrangements. Reviewing the state of the art of project finance provides a special opportunity to draw attention to the main challenges of this technique and to identify new trends.Garcia-Bernabeu, A.; Mayor Vitoria, F.; Mas Verdú, F. (2015). Project finance recent applications and future trends: the state of the art. International Journal of Business and Economics. 14(2):159-178. http://hdl.handle.net/10251/67894S15917814
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.
Measuring the deviation of the 2-3 lepton mixing from maximal with atmospheric neutrinos
The measurement of the deviation of the 2-3 leptonic mixing from maximal,
D_23 = 1/2 - sin^2(theta_23), is one of the key issues for understanding the
origin of the neutrino masses and mixing. In the three-neutrino context we
study the dependence of various observables in the atmospheric neutrinos on
D_23. We perform a global three-neutrino analysis of the atmospheric and
reactor neutrino data taking into account the effects of both the oscillations
driven by the "solar" parameters (Delta_m_21^2 and theta_12) and the 1-3
mixing. The departure from the one-dominant mass scale approximation results
into the shift of the 2-3 mixing from maximal by Delta_sin^2(theta_23) ~ 0.04,
so that D_23 ~ 0.04 +- 0.07 (1 sigma). Though value of the shift is not
statistically significant, the tendency is robust. The shift is induced by the
excess of the e-like events in the sub-GeV sample. We show that future large
scale water Cherenkov detectors can determine D_23 with accuracy of a few
percent, comparable with the sensitivity of future long baseline experiments.
Moreover, the atmospheric neutrinos will provide unique information on the sign
of the deviation (octant of theta_23).Comment: 20 pages, LaTeX2e file using RevTEX4, 6 figures and 1 table include
Supersymmetric Electroweak Renormalization of the Z-Width in the MSSM (I)
Within the framework of the MSSM, we compute the complete set of electroweak
one-loop supersymmetric quantum effects on the width of the
-boson in the on-shell renormalization scheme. Numerical analyses of the
corrections to the various partial widths into leptons and quarks are
presented. On general grounds, the average size of the electroweak SUSY
corrections to may well saturate the level of the present
theoretical uncertainties, even if considering the full supersymmetric spectrum
lying in the neighbourhood of the unaccessible LEP 200 range. Remarkably
enough, for the present values of the top quark mass, the electroweak SUSY
effects could be, globally, very close or even bigger than the electroweak SM
corrections, but opposite in sign. Therefore, in the absence of theoretical
errors, there are large regions of parameter space where one could find that,
effectively, the electroweak SM corrections are ``missing'', or even having the
``wrong'' sign. This should be helpful in discriminating between the SM and the
MSSM. However, an accurate prediction of the electroweak quantum effects on
will only be possible, if and are pinned down
in the future with enough precision.Comment: 17 p. in LaTeX. Preprint UAB-FT-343. Error in figure caption #3
corrected. Results unchange
Chaste: an open source C++ library for computational physiology and biology
Chaste - Cancer, Heart And Soft Tissue Environment - is an open source C++ library for the computational simulation of mathematical models developed for physiology and biology. Code development has been driven by two initial applications: cardiac electrophysiology and cancer development. A large number of cardiac electrophysiology studies have been enabled and performed, including high performance computational investigations of defibrillation on realistic human cardiac geometries. New models for the initiation and growth of tumours have been developed. In particular, cell-based simulations have provided novel insight into the role of stem cells in the colorectal crypt. Chaste is constantly evolving and is now being applied to a far wider range of problems. The code provides modules for handling common scientific computing components, such as meshes and solvers for ordinary and partial differential equations (ODEs/PDEs). Re-use of these components avoids the need for researchers to "re-invent the wheel" with each new project, accelerating the rate of progress in new applications. Chaste is developed using industrially-derived techniques, in particular test-driven development, to ensure code quality, re-use and reliability. In this article we provide examples that illustrate the types of problems Chaste can be used to solve, which can be run on a desktop computer. We highlight some scientific studies that have used or are using Chaste, and the insights they have provided. The source code, both for specific releases and the development version, is available to download under an open source Berkeley Software Distribution (BSD) licence at http://www.cs.ox.ac.uk/chaste, together with details of a mailing list and links to documentation and tutorials
Non-resonant leptogenesis in seesaw models with an almost conserved B-L
We review the motivations and some results on leptogenesis in seesaw models
with an almost conserved lepton number. The paper is based on a talk given at
the 5th International Symposium on Symmetries in Subatomic Physics, SSP2012.Comment: 8 pages, 1 figure. Published in the proceedings of the 5th
International Symposium on Symmetries in Subatomic Physics, SSP201
Probing neutrino non-standard interactions with atmospheric neutrino data
We have reconsidered the atmospheric neutrino anomaly in light of the laetst
data from Super-Kamiokande contained events and from Super-Kamiokande and MACRO
up-going muons. We have reanalysed the proposed solution to the atmospheric
neutrino anomaly in terms of non-standard neutrino-matter interactions (NSI) as
well as the standard nu_mu -> nu_tau oscillations (OSC). Our statistical
analysis shows that a pure NSI mechanism is now ruled out at 99%, while the
standard nu_mu -> nu_tau OSC mechanism provides a quite remarkably good
description of the anomaly. We therefore study an extended mechanism of
neutrino propagation which combines both oscillation and non-standard
neutrino-matter interactions, in order to derive limits on flavour-changing
(FC) and non-universal (NU) neutrino interactions. We obtain that the
off-diagonal flavour-changing neutrino parameter epsilon and the diagonal
non-universality neutrino parameter epsilon' are confined to -0.03 < epsilon <
0.02 and |epsilon'| < 0.05 at 99.73% CL. These limits are model independent and
they are obtained from pure neutrino-physics processes. The stability of the
neutrino oscillation solution to the atmospheric neutrino anomaly against the
presence of non-standard neutrino interactions establishes the robustness of
the near-maximal atmospheric mixing and massive-neutrino hypothesis. The best
agreement with the data is obtained for Delta_m^2 = 2.3*10^{-3} eV^2,
sin^2(2*theta) = 1, epsilon = 6.7*10^{-3} and epsilon' = 1.1*10^{-3}, although
the chi^2 function is quite flat in the epsilon and epsilon' directions for
epsilon, epsilon' -> 0.Comment: 26 pages, LaTeX file using REVTeX4, 1 table and 12 figures included.
Added a revised analysis which takes into account the new 1489-day
Super-Kamiokande and final MACRO data. The bound on NSI parameters is
considerably improve
Mass hierarchy, 2-3 mixing and CP-phase with Huge Atmospheric Neutrino Detectors
We explore the physics potential of multi-megaton scale ice or water
Cherenkov detectors with low ( GeV) threshold. Using some proposed
characteristics of the PINGU detector setup we compute the distributions of
events versus neutrino energy and zenith angle , and study
their dependence on yet unknown neutrino parameters. The
regions are identified where the distributions have the highest sensitivity to
the neutrino mass hierarchy, to the deviation of the 2-3 mixing from the
maximal one and to the CP-phase. We evaluate significance of the measurements
of the neutrino parameters and explore dependence of this significance on the
accuracy of reconstruction of the neutrino energy and direction. The effect of
degeneracy of the parameters on the sensitivities is also discussed. We
estimate the characteristics of future detectors (energy and angle resolution,
volume, etc.) required for establishing the neutrino mass hierarchy with high
confidence level. We find that the hierarchy can be identified at --
level (depending on the reconstruction accuracies) after 5 years of
PINGU operation.Comment: 39 pages, 21 figures. Description of Fig.3 correcte
Confusing non-standard neutrino interactions with oscillations at a neutrino factory
Most neutrino mass theories contain non-standard interactions (NSI) of
neutrinos which can be either non-universal (NU) or flavor-changing (FC). We
study the impact of such interactions on the determination of neutrino mixing
parameters at a neutrino factory using the so-called ``golden channels''
\pnu{e}\to\pnu{\mu} for the measurement of \theta_{13}. We show that a certain
combination of FC interactions in neutrino source and earth matter can give
exactly the same signal as oscillations arising due to \theta_{13}. This
implies that information about \theta_{13} can only be obtained if bounds on
NSI are available. Taking into account the existing bounds on FC interactions,
this leads to a drastic loss in sensitivity in \theta_{13}, at least two orders
of magnitude. A near detector at a neutrino factory offers the possibility to
obtain stringent bounds on some NSI parameters. Such near site detector
constitutes an essential ingredient of a neutrino factory and a necessary step
towards the determination of \theta_{13} and subsequent study of leptonic CP
violation.Comment: 23 pages, 5 figures, improved version, accepted for publication in
Phs. Rev. D, references adde
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