271 research outputs found
Higgs mediated Flavour Violation in 2HDMs and the MSSM -- An Overview
In these proceedings we review the flavour phenomenology of two-Higgs-doublet
models (2HDMs) and connect the results to the decoupling limit of the MSSM. We
first study the impact of FCNC constraints on the allowed parameter space of
the 2HDM and examine how recent deviations from the SM expectations in tauonic
decays (observed by BABAR) can be explained in a 2HDM with generic flavour
structure (of type III) with sizable flavour violation in the up-sector.
Afterwards, we discusses the matching of the MSSM on the 2HDM of type III. Here
we focus on the two-loop SQCD corrections to the Higgs-quark-quark couplings.Comment: Proceedings for "Les Rencontres de Physique de la Vallee d'Aoste", 8
pages, 4 figure
Chiral Enhancement in the MSSM -- An Overview
In this article I review the origin and the effects of chirally enhanced
loop-corrections in the MSSM based on Refs. [1-3]. Chiral enhancement is
related to fermion-Higgs couplings (or self-energies when the Higgs field is
replaced by its vev). I describe the resummation of these chirally-enhanced
corrections to all orders in perturbation theory and the calculation of the
effective fermion-Higgs and gaugino(higgsino)-fermion vertices. As an
application a model with radiative flavor-violation is discussed which can
solve the SUSY-CP and the SUSY-flavor problem while it is still capable of
explaining the observed deviation from the SM in the Bs mixing phase.Comment: Talk given at 25th Les Rencontres de Physique de La Vallee d'Aoste,
La Thuile, Aosta Valley, Italy, 27 Feb - 5 Mar 201
Flavor violation in the MSSM and implications for top and squark searches at colliders
In this article I review some connections between flavor physics and collider
physics. The first part discusses the effect of right-handed charged currents
on the determination of the CKM elements V_ub. It is shown that such an
effective right-handed W-coupling can be generated in the MSSM which would lead
to a sizable enhancement of single-top production at the LHC. The second part
of this article focuses on the constraints on the mass splitting between
left-handed squarks from Kaon and D mixing. Such a mass splitting has
interesting consequences for squark decay chains at colliders.Comment: 11 pages, 4 figures. Presented at Linear Collider 2011: Understanding
QCD at Linear Colliders in searching for old and new physics, 12-16 September
2011, ECT*, Trento, Ital
Tauonic B decays in 2HDMs and the MSSM in the decoupling limit
In these proceedings we review two aspects of 2HDMs with generic Yukawa
structures. The first part considers how recent deviations from the SM
expectations in tauonic B decays (observed by BABAR) can be explained in a 2HDM
of type III with sizable flavour violation in the up-sector. The second part
discusses the matching of the MSSM on the 2HDM of type III. Here we focus on
the recently calculated two-loop SQCD corrections to the Higgs-quark-quark
couplings.Comment: 6 pages, 3 figures, proceedings of: Prospects for Charged Higgs
Discovery at Colliders - Charged 201
New Physics in decays
While the LHC did not observe direct evidence for physics beyond the standard
model, indirect hints for new physics were uncovered in the flavour sector in
the decays , ,
, and . Each
observable deviates from the SM predictions at the level only,
but combining all data via a global fit, one finds
difference for NP compared to the SM and combining with one obtains . While and can be naturally explained by an extended
Higgs sector, the anomalies point at a gauge boson.
However, it is also possible to explain and simultaneously with leptoquarks while their effect in
is far too small to account for current data. Combining a
2HDM with a gauged symmetry allows for explaining the anomalies in combination with , predicting
interesting correlations with . In the light of these deviations
from the SM we also discuss the possibilities of observing lepton flavour
violating decays (e.g. and
).Comment: 9 pages, 6 figures, proceedings for "Flavour changing and conserving
processes" 2015, references adde
Challenges for New Physics in the Flavour Sector
In these proceedings I present a personal perspective of the challenges for
new physics (NP) searches in the flavour sector. Since the CKM mechanism of
flavour violation has been established to a very high precision, we know that
physics beyond the Standard Model can only contribute sub-dominantly.
Therefore, any realistic model of physics beyond the Standard Model (SM) must
respect the stringent constrains from flavour observables like ,
, processes etc., in a first step. In a second
step, it is interesting to ask the question if some deviations from the SM
predictions (like the anomalous magnetic moment of the muon or recently
observed discrepancies in tauonic decays or ) can be
explained by a model of NP without violating bounds from other observables.Comment: Presented at the 2014 Flavour Physics and CP Violation (FPCP-2014),
Marseille, France, May 26-30 2014, 27 pages, 6 figures, references adde
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