1,314 research outputs found
Probing the Goldstone equivalence theorem in Heavy Weak Doublet Decays
This paper investigates the decays from heavy higgsino-like weak-doublets
into Z, h bosons and missing particles. When pair-produced at the LHC, the
subsequent Z, h to 2l, 2b decays in the doublet decay cascade can yield 4l, 2l
2b, and 4b + MET + jets final states. Mutual observation of any two of these
channels would provide information on the the associated doublets' decay
branching fractions into a Z or h, thereby probing the Goldstone equivalence
relation, shedding additional light on the Higgs sector of beyond the Standard
Model theories, and facilitating the discrimination of various contending
models, in turn. We compare the Z/h decay ratio expected in the Minimal
Supersymmetric model, the Next-to Minimal Supersymmetric model and a minimal
singlet-doublet dark matter model. Additionally, we conduct a full Monte Carlo
analysis of the prospects for detecting the targeted final states during 14 TeV
running of the LHC in the context of a representative NMSSM benchmark model.Comment: As accepted to PRD; 15 pages, 12 figures, 5 table
Sensitivity to Z-prime and non-standard neutrino interactions from ultra-low threshold neutrino-nucleus coherent scattering
We discuss prospects for probing Z-prime and non-standard neutrino
interactions using neutrino-nucleus coherent scattering with ultra-low energy
(~ 10 eV) threshold Si and Ge detectors. The analysis is performed in the
context of a specific and contemporary reactor-based experimental proposal,
developed in cooperation with the Nuclear Science Center at Texas A&M
University, and referencing available technology based upon economical and
scalable detector arrays. For expected exposures, we show that sensitivity to
the Z-prime mass is on the order of several TeV, and is complementary to the
LHC search with low mass detectors in the near term. This technology is also
shown to provide sensitivity to the neutrino magnetic moment, at a level that
surpasses terrestrial limits, and is competitive with more stringent
astrophysical bounds. We demonstrate the benefits of combining silicon and
germanium detectors for distinguishing between classes of models of new
physics, and for suppressing correlated systematic uncertainties.Comment: As published in PRD; 13 pages, 7 figure
Non-standard interactions of solar neutrinos in dark matter experiments
Non-standard neutrino interactions (NSI) affect both their propagation
through matter and their detection, with bounds on NSI parameters coming from
various astrophysical and terrestrial neutrino experiments. In this paper, we
show that NSI can be probed in future direct dark matter detection experiments
through both elastic neutrino-electron scattering and coherent neutrino-nucleus
scattering, and that these channels provide complementary probes of NSI. We
show NSI can increase the event rate due to solar neutrinos, with a sharp
increase for lower nuclear recoil energy thresholds that are within reach for
upcoming detectors. We also identify an interference range of NSI parameters
for which the rate is reduced by approximately 40\%. Finally, we show that the
"dark side" solution for the solar neutrino mixing angle may be discovered at
forthcoming direct detection experiments.Comment: 12 pages, 5 figure
A 125.5 GeV Higgs Boson in F-SU(5): Imminently Observable Proton Decay, A 130 GeV Gamma-ray Line, and SUSY Multijets & Light Stops at the LHC8
We establish that the light Higgs boson mass in the context of the No-Scale
Flipped SU(5) GUT with TeV scale vector-like matter multiplets (flippons) is
consistent with m_h = 125.5+-0.5 GeV in the region of the best supersymmetry
(SUSY) spectrum fit to low statistics data excesses observed by ATLAS in
multijet and light stop 5/fb SUSY searches at the LHC7. Simultaneous
satisfaction of these disparate goals is achieved by employing a minor decrease
in the SU(5) partial unification scale M_{32} to lower the flippon mass,
inducing a larger Higgs boson mass shift from the flippon loops. The reduction
in M_{32}, which is facilitated by a phenomenologically favorable reduction of
the low-energy strong coupling constant, moreover suggests an imminently
observable (e|mu)^+ pi^0 proton decay with a central value time scale of
1.7x10^34 years. At the same point in the model space, we find a lightest
neutralino mass of m_{\chi} = 145 GeV, which is suitable for the production of
130 GeV monochromatic gamma-rays through annihilations yielding associated
Z-bosons; a signal with this energy signature has been identified within
observations of the galactic center by the FERMI-LAT Space Telescope. In
conjunction with direct correlations to the fate of the ATLAS multijet and
light stop production channels presently being tested at the LHC8, we suggest
that the reality of a 125.5 GeV Higgs boson affords a particularly rich company
of specific and imminently testable associated observables.Comment: European Physical Journal C Version; 10 Pages, 2 Figures, 2 Table
Non-trivial Supersymmetry Correlations between ATLAS and CMS Observations
We present definite correlations between the CMS 5 \fb all-hadronic search
employing the stransverse mass variable and the ATLAS 5 \fb
all-hadronic and multijet supersymmetry (SUSY) searches, suggesting the
possibility that both the ATLAS and CMS experiments are already registering a
faint but legitimate SUSY signal at the LHC. We isolate this prospective mutual
productivity beyond the Standard Model in the framework of the supersymmetric
No-Scale Flipped (5) grand unified theory, supplemented with extra
vector-like matter (flippons). Evident overproduction is observed in three CMS
\mt2 and four ATLAS hadronic and multijet signal regions, where a \x2 fitting
procedure of the CMS 5 \fb \mt2 search establishes a best fit SUSY mass in
sharp agreement with corresponding ATLAS searches of equivalently heightened
signal significance. We believe this correlated behavior across two distinct
experiments at precisely the same SUSY mass scale to be highly non-trivial, and
potentially indicative of an existing 5 \fb LHC reach into a pervasive physical
supersymmetry framework.Comment: 6 Pages, 2 Figure
Profumo di SUSY: Suggestive Correlations in the ATLAS and CMS High Jet Multiplicity Data
We present persistently amassing evidence that the CMS and ATLAS
Collaborations may indeed be already registering supersymmetry events at the
Large Hadron Collider (LHC). Our analysis is performed in the context of a
highly phenomenologically favorable model named No-Scale F-SU(5), which
represents the unification of the F-lipped SU(5) Grand Unified Theory (GUT),
two pairs of hypothetical TeV-scale vector-like supersymmetric multiplets
derived out of F-Theory, and the dynamically established boundary conditions of
No-Scale supergravity. We document highly suggestive correlations between the
first inverse femtobarn of observations by CMS and ATLAS, where seductive
excesses in multijet events, particularly those with nine or more jets, are
unambiguously accounted for by a precision Monte-Carlo simulation of the
F-SU(5) model space. This intimate correspondence is optimized by a unified
gaugino mass in the neighborhood of M_{1/2}=518 GeV. We supplement this
analysis by extrapolating for the expected data profile to be realized with
five inverse femtobarns of integrated luminosity, as expected to be observed at
the LHC by the conclusion of 2011. Significantly, we find that this luminosity
may be sufficient to constitute a SUSY discovery for the favored benchmark
spectrum. Indeed, the winds wafting our way from Geneva may already be heavy
with the delicate perfume of Supersymmetry.Comment: 15 pages, 5 figures, 6 table
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