101 research outputs found
A light NMSSM pseudoscalar Higgs boson at the LHC Run 2
We revisit the light pseudoscalar in the Next-to-Minimal Supersymmetric
Standard Model (NMSSM) with partial universality at some high unification scale
in order to delineate the parameter space regions consistent with up-to-date
theoretical and experimental constraints and examine to what extent this state
can be probed by the Large Hadron Collider (LHC) during Run 2. We find that it
can be accessible through a variety of signatures proceeding via and/or , the former assuming hadronic decays and the
latter two -tags within a fat jet or two separate slim ones. Herein, the
light pseudoscalar state is produced from a heavy Higgs boson decay in either
pairs or singly in association with a boson (in turn decaying into
electrons/muons).Comment: 6 pages, 6 figures, 1 table - Talk given at the Toyama International
Workshop on Higgs as a Probe of New Physics 2015, 11-15, February, 2015,
Toyama, Japa
Long lived charginos in Natural SUSY?
Supersymmetric models with a small neutralino-chargino mass difference, and
as a result metastable charginos, have been a popular topic of investigation in
collider phenomenology, e.g. in anomaly-mediated models of supersymmetry
breaking. Recently, the absence of any supersymmetric signal at the 8 TeV LHC
data has led to significant interest in the so-called Natural SUSY models with
light higgsinos. These models also have a naturally small neutralino-chargino
mass difference. However, we show here that when relevant indirect constraints
from results at the LHC and elsewhere are applied, this possibility is heavily
constrained within the Minimal Supersymmetric Standard Model (MSSM): massive
metastable higgsinos are not a signature of Natural SUSY.Comment: Extended discussion, updated references, matches version to appear in
JHE
Status and discovery prospects for light pseudoscalars in the NMSSM
While most BSM searches at the LHC focus on heavy new states, the NMSSM
contains the possibility of new light states that have escaped detection due to
their singlet nature. Here we focus on light pseudoscalars, investigating the
parameter space impact of recent LHC searches for such light states stemming
from the decay of the 125 GeV Higgs boson. It is shown that, though direct
searches can not yet compete with the requirement of the 125 GeV scalar having
SM-like couplings, the searches are touching the allowed parameter space and
should make a phenomenological impact in the near future.Comment: To appear in the proceedings for EPS-HEP 201
Gravitino Dark Matter and the Flavour Structure of R-violating Operators
We study gravitino dark matter and slow gravitino decays within the framework
of R-violating supersymmetry, with particular emphasis on the flavour
dependence of the branching ratios and the allowed R-violating couplings. The
dominant decay modes and final state products turn out to be very sensitive to
the R-violating hierarchies. Mixing effects can be crucial in correctly
deriving the relative magnitude of the various contributions, particularly for
heavy flavours with phase space suppression. The study of the strength of
different decay rates for the gravitino is also correlated to collider
signatures expected from decays of the Next-to-Lightest Supersymmetric Particle
(NLSP) and to single superparticle production
Gravitino dark matter and the flavour structure of R-violating operators
We study gravitino dark matter and slow gravitino decays within the framework of R-violating supersymmetry, with particular emphasis on the flavour dependence of the branching ratios and the allowed R-violating couplings. The dominant decay modes and final state products turn out to be very sensitive to the R-violating hierarchies. Mixing effects can be crucial in correctly deriving the relative magnitude of the various contributions, particularly for heavy flavours with phase space suppression. The study of the strength of different decay rates for the gravitino is also correlated to collider signatures expected from decays of the Next-to-Lightest Supersymmetric Particle (NLSP) and to single superparticle production.publishedVersio
Photon, Neutrino and Charged Particle Spectra from R-violating Gravitino Decays
We study photonic, neutrino and charged particle signatures from slow decays
of gravitino dark matter in supersymmetric theories where R-parity is
explicitly broken by trilinear operators. Photons and (anti-)fermions from loop
and tree-level processes give rise to spectra with distinct features, which, if
observed, can give crucial input on the possible mass of the gravitino and the
magnitude and flavour structure of R-violating operators. Within this
framework, we make detailed comparisons of the theoretical predictions to the
recent experimental data from PAMELA, ATIC and Fermi LAT.Comment: Version published in Phys. Lett.
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