8,276 research outputs found
R-Parity Violation and the HERA Events
The excess in high-Q^2 events at HERA is introduced and possible explanations
within the framework of R-parity violating supersymmetry are discussed.Comment: LaTeX, 5 pages, 2 figures. Talk presented at the International
Workshop on Physics "Beyond the Standard Model: from Theory to Experiment",
Valencia, Spain (October 13 - 17, 1997), to appear in the Proceeding
A New Type of Singularity Theorem
A new type of singularity theorem, based on spatial averages of physical
quantities, is presented and discussed. Alternatively, the results inform us of
when a spacetime can be singularity-free. This theorem provides a decisive
observational difference between singular and non-singular, globally
hyperbolic, open cosmological models.Comment: 6 pages, no figures. Contribution to appear in the Proceedings of the
Spanish Relativity Meeting ERE-07, "Relativistic Astrophysics and Cosmology
Solar neutrino: Flux, cosmic rays and the 11 year solar cycle
It is shown that the results of maximum likelihood treatment of Monte Carlo simulation with constant production rate of 7.6 SNU and 1.Epsilon SNU are consistent with the constant production rate when the tests of hypotheses (e.g., t-test, sigma squared-test, Wilcoxon-Mann-Whitney test, run test, etc.) are applied to the two groups of data formed from sunspot minimum range and sunspot maximum range, whereas the real data pulsates with the solar activity cycle. It is shown that SN flux-change is in opposition phase to the solar activity cycle and lags behind the latter by about one year. A correlation between SN flux and the cosmic rays is suggested
The Unforeseen Developments Clause in Safeguards under the WTO: Confusions in Compliance
In this article the author explores in detail the “unforeseen developments†requirement in the Agreement on Safeguards under the WTO. The author seeks to answer questions such as whether the requirement (i.e., unforeseen developments must be demonstrated in order for safeguard measures to be justified) is an integral part of the Agreement on Safeguards, and how the subjectivity associated with this requirement contributes to the difficulty of constructing a reasoned and adequate account of the causal chain. The article also includes within its scope a brief analysis of larger issues such as the political and economic rationale behind safeguard measures, and how ambiguities in the Agreement on Safeguards can destabilize the discipline of safeguards and defeat one of its major purposes - to help countries nurture their infant industries. Finally, the article reflects upon how India, being one of the leading users of safeguard measures as of 2008, is likely to be affected by unclear areas in the present legislation such as the unforeseen developments clause.India, international trade, safeguards, unforeseen developments, WTO, Industrial Organization, Institutional and Behavioral Economics, International Development, International Relations/Trade, Political Economy,
Next to Minimal Higgs : Mass Bounds and Search Prospects
The Standard Model of electroweak interactions has one scalar doublet. The
minimal extension of this sector is effected by adding a neutral, singlet
scalar field. Depending on whether the singlet field has a non-zero vacuum
expectation value, x, or not, the scenario has quite distinctive predictions.
In particular, x unequal to 0 produces a mixing between the usual SU(2) doublet
and the singlet, giving rise to two physical states and a goldstone boson with
non-vanishing coupling to these. Presence of this coupling modifies the 2 jets
+ missing energy signal of the Bjorken process at LEP. We update the bounds on
the Higgs mass using the LEP-1 data. We then explore, using parton-level Monte
Carlo event generators, the production of these scalars at the LHC via
gluon-gluon fusion and subsequent detection. We compare the signals with the
expected backgrounds.Comment: 16 pages and 7 Postscript figures, Late
A note on the neutrino mass implications of the K2K experiment
The K2K experiment has presented the first results on the observation of
nu_mu. They show a depletion compared to the expectations and are consistent
with neutrino oscillations with a mass-splitting in the range favoured by the
Super-Kamiokande atmospheric neutrino measurements. Here we examine the extent
by which the range of Delta m^2 obtained from the K2K measurements can vary due
to the uncertainties in the flux, cross-section, and detector efficiency.Comment: 8 pages LaTeX, 2 postscript figures, J. Phys. G. (to appear
Three-Higgs-doublet model under A4 symmetry implies alignment
A model with three scalar doublets can be conveniently accommodated within an
A4 symmetric framework. The A4 symmetry permits only a restricted form for the
scalar potential. We show that for the global minima of this potential
alignment follows as a natural consequence. We also verify that in every case
positivity and unitarity constraints are satisfactorily met.Comment: 17 pages, v2: References added, some changes in text, to appear in
JHE
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