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### The Top Triangle Moose

We introduce a deconstructed model that incorporates both Higgsless and
top-color mechanisms. The model alleviates the typical tension in Higgsless
models between obtaining the correct top quark mass and keeping delta-rho
small. It does so by singling out the top quark mass generation as arising from
a Yukawa coupling to an effective top-Higgs which develops a small vacuum
expectation value, while electroweak symmetry breaking results largely from a
Higgsless mechanism. As a result, the heavy partners of the SM fermions can be
light enough to be seen at the LHC

### Top triangle moose: Combining Higgsless and topcolor mechanisms for mass generation

We present the details of a deconstructed model that incorporates both Higgsless and top-color mechanisms. The model alleviates the tension between obtaining the correct top quark mass and keeping ĪĻ small that exists in many Higgsless models. It does so by singling out the top quark mass generation as arising from a Yukawa coupling to an effective top Higgs which develops a small vacuum expectation value, while electroweak symmetry breaking results largely from a Higgsless mechanism. As a result, the heavy partners of the SM fermions can be light enough to be seen at the LHC. After presenting the model, we detail the phenomenology, showing that for a broad range of masses, these heavy fermions are discoverable at the LHC. Ā© 2009 The American Physical Society

### High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.

Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions

### Spin and Chirality Effects in Antler-Topology Processes at High Energy $e^+e^-$ Colliders

We perform a model-independent investigation of spin and chirality
correlation effects in the antler-topology processes
$e^+e^-\to\mathcal{P}^+\mathcal{P}^-\to (\ell^+ \mathcal{D}^0)
(\ell^-\mathcal{\bar{D}}^0)$ at high energy $e^+e^-$ colliders with polarized
beams. Generally the production process $e^+e^-\to\mathcal{P}^+\mathcal{P}^-$
can occur not only through the $s$-channel exchange of vector bosons,
$\mathcal{V}^0$, including the neutral Standard Model (SM) gauge bosons,
$\gamma$ and $Z$, but also through the $s$- and $t$-channel exchanges of new
neutral states, $\mathcal{S}^0$ and $\mathcal{T}^0$, and the $u$-channel
exchange of new doubly-charged states, $\mathcal{U}^{--}$. The general set of
(non-chiral) three-point couplings of the new particles and leptons allowed in
a renormalizable quantum field theory is considered. The general spin and
chirality analysis is based on the threshold behavior of the excitation curves
for $\mathcal{P}^+\mathcal{P}^-$ pair production in $e^+e^-$ collisions with
longitudinal and transverse polarized beams, the angular distributions in the
production process and also the production-decay angular correlations. In the
first step, we present the observables in the helicity formalism. Subsequently,
we show how a set of observables can be designed for determining the spins and
chiral structures of the new particles without any model assumptions. Finally,
taking into account a typical set of approximately chiral invariant scenarios,
we demonstrate how the spin and chirality effects can be probed experimentally
at a high energy $e^+e^-$ collider.Comment: 50 pages, 14 figures, 6 tables, matches version published in EPJ

### Dirac Gauginos, Negative Supertraces and Gauge Mediation

In an attempt to maximize General Gauge Mediated parameter space, I propose
simple models in which gauginos and scalars are generated from disconnected
mechanisms. In my models Dirac gauginos are generated through the supersoft
mechanism, while independent R-symmetric scalar masses are generated through
operators involving non-zero messenger supertrace. I propose several new
methods for generating negative messenger supertraces which result in viable
positive mass squareds for MSSM scalars. The resultant spectra are novel,
compressed and may contain light fermionic SM adjoint fields.Comment: 16 pages 3 figure

### Momentum asymmetries as CP violating observables

Three body decays can exhibit CP violation that arises from interfering
diagrams with different orderings of the final state particles. We construct
several momentum asymmetry observables that are accessible in a hadron collider
environment where some of the final state particles are not reconstructed and
not all the kinematic information can be extracted. We discuss the
complications that arise from the different possible production mechanisms of
the decaying particle. Examples involving heavy neutralino decays in
supersymmetric theories and heavy Majorana neutrino decays in Type-I seesaw
models are examined.Comment: 20 pages, 9 figures. Clarifying comments and one reference added,
matches published versio

### The Universal Real Projective Plane: LHC phenomenology at one Loop

The Real Projective Plane is the lowest dimensional orbifold which, when
combined with the usual Minkowski space-time, gives rise to a unique model in
six flat dimensions possessing an exact Kaluza Klein (KK) parity as a relic
symmetry of the broken six dimensional Lorentz group. As a consequence of this
property, any model formulated on this background will include a stable Dark
Matter candidate. Loop corrections play a crucial role because they remove mass
degeneracy in the tiers of KK modes and induce new couplings which mediate
decays. We study the full one loop structure of the corrections by means of
counter-terms localised on the two singular points. As an application, the
phenomenology of the (2,0) and (0,2) tiers is discussed at the LHC. We identify
promising signatures with single and di-lepton, top antitop and 4 tops: in the
dilepton channel, present data from CMS and ATLAS may already exclude KK masses
up to 250 GeV, while by next year they may cover the whole mass range preferred
by WMAP data.Comment: 45 pages, 3 figure

### Discovering the composite Higgs through the decay of a heavy fermion

A possible composite nature of the Higgs could be revealed at the early stage
of the LHC, by analyzing the channels where the Higgs is produced from the
decay of a heavy fermion. The Higgs production from a singly-produced heavy
bottom, in particular, proves to be a promising channel. For a value \lambda=3
of the Higgs coupling to a heavy bottom, for example, we find that, considering
a 125 GeV Higgs which decays into a pair of b-quarks, a discovery is possible
at the 8 TeV LHC with 30 fb^{-1} if the heavy bottom is lighter than roughly
530 GeV (while an observation is possible for heavy bottom masses up to 650
GeV). Such a relatively light heavy bottom is realistic in composite Higgs
models of the type considered and, up to now, experimentally allowed. At
\sqrt{s}=14 TeV the LHC sensitivity on the channel increases significantly.
With \lambda=3 a discovery can occur, with 100 fb^{-1}, for heavy bottom masses
up to 1040 GeV. In the case the heavy bottom was as light as 500 GeV, the 14
TeV LHC would be sensitive to the measure of the \lambda\ coupling in basically
the full range \lambda>1 predicted by the theory.Comment: 25 pp. v2: Minor changes. v3: Version accepted for publication in
JHEP. v4: typos fixe

### Logarithmic Corrections to Schwarzschild and Other Non-extremal Black Hole Entropy in Different Dimensions

Euclidean gravity method has been successful in computing logarithmic
corrections to extremal black hole entropy in terms of low energy data, and
gives results in perfect agreement with the microscopic results in string
theory. Motivated by this success we apply Euclidean gravity to compute
logarithmic corrections to the entropy of various non-extremal black holes in
different dimensions, taking special care of integration over the zero modes
and keeping track of the ensemble in which the computation is done. These
results provide strong constraint on any ultraviolet completion of the theory
if the latter is able to give an independent computation of the entropy of
non-extremal black holes from microscopic description. For Schwarzschild black
holes in four space-time dimensions the macroscopic result seems to disagree
with the existing result in loop quantum gravity.Comment: LaTeX, 40 pages; corrected small typos and added reference

### RECAST: Extending the Impact of Existing Analyses

Searches for new physics by experimental collaborations represent a
significant investment in time and resources. Often these searches are
sensitive to a broader class of models than they were originally designed to
test. We aim to extend the impact of existing searches through a technique we
call 'recasting'. After considering several examples, which illustrate the
issues and subtleties involved, we present RECAST, a framework designed to
facilitate the usage of this technique.Comment: 13 pages, 4 figure

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