1,608 research outputs found
Sparticle Spectroscopy with Neutralino Dark matter from t-b-tau Quasi-Yukawa Unification
We consider two classes of t-b-tau quasi-Yukawa unification scenarios which
can arise from realistic supersymmetric SO(10) and SU(4)_C X SU(2)_L X SU(2)_R
models. We show that these scenarios can be successfully implemented in the
CMSSM and NUHM1 frameworks, and yields a variety of sparticle spectra with WMAP
compatible neutralino dark matter. In NUHM1 we find bino-higgsino dark matter
as well as the stau coannihilation and A-funnel solutions. The CMSSM case
yields the stau coannihilation and A-funnel solutions. The gluino and squark
masses are found to lie in the TeV range.Comment: 21 pages, 12 figures, 2 table
Observable Gravity Waves from Supersymmetric Hybrid Inflation II
It is shown that a tensor-to-scalar ratio close to r = 0.03, which can be
observed by Planck, is realized in supersymmetric hybrid inflation models with
TeV-scale soft supersymmetry breaking terms. This extends our previous
analysis, which also found r <~ 0.03 but employed intermediate scale soft
terms. Other cosmological observables such as the scalar spectral index are in
good agreement with the WMAP data.Comment: 4 pages, 4 figure
Axions and the dark matter of the universe
Spin(10) axion models are constructed which offer the possibility that axions comprise all or a significant part of the dark matter of the Universe
Establishing a Performance Testing Approach for E-Learning Applications
Most of the E-Learning applications perform poorly in motivating employees to learn. To solve this problem, we need to examine what workplace e-learning requires and how workplace e-learning systems should be developed in line with those requirements. We investigated the problem by identifying the fundamental elements of the workplace learning environment including the learner, organization, learning content and social context, and their relationships. We found that workplace e-learning should align individual and organizational learning needs, connect learning and work performance, and support social interaction among individuals. To achieve this, a performance testing approach is proposed. Key performance indicators are utilized to clarify organizational goals, make sense of work context and requests on work performance, and accordingly help employees set up rational learning objectives and enhance their learning process. Using this approach, prototype system has been developed and a set of experiments have been conducted to demonstrate the effectiveness of the approach. This paper also presents the use of software verification, validation and testing technique, traditionally used in the software development, in the design and implementation of E-Learning products. We examine the ways one can apply testing techniques in E-Learning life cycle. This includes the strategy adoption for the selection of testing technique along with tool acquisition and measurement. The objective is to develop a collaborative approach involving software testing and educational methodology
Red Spectral Tilt and Observable Gravity Waves in Shifted Hybrid Inflation
We consider supersymmetric shifted hybrid inflation models with a red tilted
scalar spectral index n_s in agreement with the WMAP 7-yr central value. If
non-minimal supergravity corrections are included, these models can also
support a tensor-to-scalar ratio as large as r = 0.02, which may be observable
by the Planck Satellite. In contrast to the standard supersymmetric hybrid
inflation scenario, topological defects produced via gauge symmetry breaking
are inflated away in the shifted version of the theory.Comment: 22 pages, 4 figures, and 1 tabl
Coleman-Weinberg Potential In Good Agreement With WMAP
We briefly summarize and update a class of inflationary models from the early
eighties based on a quartic (Coleman-Weinberg) potential for a gauge singlet
scalar (inflaton) field. For vacuum energy scales comparable to the grand
unification scale, the scalar spectral index n_s=0.94-0.97, in very good
agreement with the WMAP three year results. The tensor to scalar ratio r<~0.14,
while alpha=dn/dlnk is =~-10^-3. An SO(10) version naturally explains the
observed baryon asymmetry via non-thermal leptogenesis.Comment: v1: 6 pages, 1 table. v2: minor corrections. v3: 8 pages, added some
details, comments, references and 3 figures. v4: minor corrections, published
versio
Dark Matter, Sparticle Spectroscopy and Muon in
We explore the sparticle mass spectra including LSP dark matter within the
framework of supersymmetric (422)
models, taking into account the constraints from extensive LHC and cold dark
matter searches. The soft supersymmetry-breaking parameters at can be
non-universal, but consistent with the 422 symmetry. We identify a variety of
coannihilation scenarios compatible with LSP dark matter, and study the
implications for future supersymmetry searches and the ongoing muon g-2
experiment.Comment: 21 pages, 8 fig
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