544 research outputs found
Minimal Seesaw as an Ultraviolet Insensitive Cure for the Problems of Anomaly Mediation
We show that an intermediate scale supersymmetric left-right seesaw scenario
with automatic R-parity conservation can cure the problem of tachyonic slepton
masses that arises when supersymmetry is broken by anomaly mediation, while
preserving ultraviolet insensitivity. The reason for this is the existence of
light B - L = 2 higgses with yukawa couplings to the charged leptons. We find
these theories to have distinct predictions compared to the usual mSUGRA and
gauge mediated models as well as the minimal AMSB models. Such predictions
include a condensed gaugino mass spectrum and possibly a correspondingly
condensed sfermion spectrum.Comment: 19 pages, 1 figur
Running with Triplets: How Slepton Masses Change With Doubly-Charged Higgses
We examine the slepton masses of SUSYLR models and how they change due the
presence of light-doubly charged higgs bosons. We discover that the measurement
of the slepton masses could bound and even predict the value of the third
generation Yukawa coupling of leptons to the SU(2)_R Triplets. We also consider
the unification prospects for this model with the addition of left-handed, B -
L = 0 triplets--a model we call the Triplet Extended Supersymmetric Standard
Model (TESSM). Finally, we discuss the changes in the slepton masses due to the
presence of the SU(2)_L triplets.Comment: 20 pages, 6 figures, 4 table
When Anomaly Mediation is UV Sensitive
Despite its successes---such as solving the supersymmetric flavor
problem---anomaly mediated supersymmetry breaking is untenable because of its
prediction of tachyonic sleptons. An appealing solution to this problem was
proposed by Pomarol and Rattazzi where a threshold controlled by a light field
deflects the anomaly mediated supersymmetry breaking trajectory, thus evading
tachyonic sleptons. In this paper we examine an alternate class of deflection
models where the non-supersymmetric threshold is accompanied by a heavy,
instead of light, singlet. The low energy form of this model is the so-called
extended anomaly mediation proposed by Nelson and Weiner, but with potential
for a much higher deflection threshold. The existence of this high deflection
threshold implies that the space of anomaly mediated supersymmetry breaking
deflecting models is larger than previously thought.Comment: 14 pages, 1 figure (version to appear in JHEP
Seesaw Extended MSSM and Anomaly Mediation without Tachyonic Sleptons
Superconformal anomalies provide an elegant and economical way to understand
the soft breaking parameters in SUSY models; however, implementing them leads
to the several undesirable features including: tachyonic sleptons and
electroweak symmetry breaking problems in both the MSSM and the NMSSM. Since
these two theories also have the additonal problem of massless neutrinos, we
have reconsidered the AMSB problems in a class of models that extends the NMSSM
to explain small neutrino masses via the seesaw mechanism. In a recent paper,
we showed that for a class of minimal left-right extensions, a built-in
mechanism exists which naturally solves the tachyonic slepton problem and
provides new alternatives to the MSSM that also have automatic R-parity
conservation. In this paper, we discuss how electroweak symmetry breaking
arises in this model through an NMSSM-like low energy theory with a singlet
VEV, induced by the structure of the left-right extension and of the right
magnitude. We then study the phenomenological issues and find: the LSP is an
Higgsino-wino mix, new phenomenology for chargino decays to the LSP, degenerate
same generation sleptons and a potential for a mild squark-slepton degeneracy.
We also discuss possible collider signatures and the feasibility of dark matter
in this model.Comment: 40 pages, 10 figures, 5 tables; v3: Added addendum and three new
references; v4: Added reference that was inadvertently omitte
Fiber Acoustic Waveguide : A Sensor Candidate
Sensor development plays a key role in the field of nondestructive evaluation and process control. The annual fiber optic sensor market alone is a multimillion dollar business (1). Acoustic waves are about five orders of magnitude slower than optical waves and can also be guided in cladded glass fibers, similar to optical fibers, with low loss and low dispersion (2–7). Fiber acoustic waveguides are believed to be a very attractive and basic component for further sensor development (8). In this paper a brief theoretical description of a weakly guiding acoustic fiber (7) is given. The material selection criteria for the core and the cladding of the fiber guide, the properties of single-mode operation, and some sensing mechanisms for temperature and pressure variations are discussed. The acoustic waveguide with a liquid core is also considered
Correction to: Clinical management of ageing people living with HIV in Europe: the view of the care providers.
info:eu-repo/semantics/publishedVersio
An Emerging Natural History in the Development, Mechanisms and Worldwide Prevalence of Major Mental Disorders
Conciliating recent findings from molecular genetics, evolutionary biology, and clinical observations together point to new understandings regarding the mechanism, development and the persistent worldwide prevalence of major mental disorders (MMDs),
which should be considered the result of an evolutionary downside trade off. Temperamental/trait variability, by facilitating choices
for individual and group responses, confers robustness flexibility and resilience crucial to success of our species. Extreme temperamental variants, originating evolutionarily from the asocial aspect of human nature, also constitute the premorbid personality
of the disorders. The latter create vulnerable individuals out of whom some will develop MMDs but at much higher rate to that of the general population. Significantly, similar temperamental “lopsidedness� enables many of these vulnerable individuals, if intelligent, tenacious, and curious, to be creative and contribute to our survival while some may also develop MMDs. All have a common neural-developmental origin and share characteristics in their clinical expression and pharmacological responses also expressed as mixed syndromes or alternating ones over time. Over-pruning of synaptic neurons may be considered the trigger of such occurrences
or conversely, the failure to prevent them in spite of it. The symptoms of the major mental disorders are made up of antithetical substitutes as an expression of a disturbed over-all synchronizing property of brain function for all higher faculties previously unconsidered in their modeling. The concomitant presence of psychosis is a generic common occurrence
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