2,147 research outputs found
Precision predictions for associated gluino-gaugino production at the LHC
Now that the mass limits for gluinos have been pushed to the few-TeV range,
they might only be visible at the LHC in associated production with lighter
gauginos. We compute the corresponding cross section at next-to-leading
logarithmic (NLL) and next-to-leading order (NLO) precision in the QCD coupling
constant. The resulting expressions are implemented in the public code
RESUMMINO and can be directly used in the corresponding experimental searches.Comment: 5 pages, 4 figures. Proceedings of the EPS Conference on High-Energy
Physics (EPS-HEP 2017), Venice, Ital
Transverse-Momentum Resummation for Slepton-Pair Production at the LHC
We perform a first precision calculation of the transverse-momentum (q_T)
distribution of slepton pair and slepton-sneutrino associated production at the
CERN Large Hadron Collider (LHC). We implement soft-gluon resummation at the
next-to-leading logarithmic (NLL) level and consistently match the obtained
result to the pure fixed-order perturbative result at leading order (LO) in the
QCD coupling constant, i.e. O(alpha_s). We give numerical predictions for
stau_1 stau_1^* and stau_1 sneutrino_tau^* + stau_1^* sneutrino_tau production,
also implementing recent parameterizations of non-perturbative effects. The
results show a relevant contribution of resummation both in the small and
intermediate q_T-regions and little dependence on unphysical scales and
non-perturbative contributions.Comment: 4 pages, 2 figure
Precision predictions for direct gaugino and slepton production at the LHC
The search for electroweak superpartners has recently moved to the centre of
interest at the LHC. We provide the currently most precise theoretical
predictions for these particles, use them to assess the precision of parton
shower simulations, and reanalyse public experimental results assuming more
general decompositions of gauginos and sleptons.Comment: 5 pages, 2 tables, 5 figures, proceedings of ICHEP 201
Squark and Gaugino Hadroproduction and Decays in Non-Minimal Flavour Violating Supersymmetry
We present an extensive analysis of squark and gaugino hadroproduction and
decays in non-minimal flavour violating supersymmetry. We employ the so-called
super-CKM basis to define the possible misalignment of quark and squark
rotations, and we use generalized (possibly complex) charges to define the
mutual couplings of (s)quarks and gauge bosons/gauginos. The cross sections for
all squark-(anti-)squark/gaugino pair and squark-gaugino associated production
processes as well as their decay widths are then given in compact analytic
form. For four different constrained supersymmetry breaking models with
non-minimal flavour violation in the second/third generation squark sector
only, we establish the parameter space regions allowed/favoured by low-energy,
electroweak precision, and cosmological constraints and display the chirality
and flavour decomposition of all up- and down-type squark mass eigenstates.
Finally, we compute numerically the dependence of a representative sample of
production cross sections at the LHC on the off-diagonal mass matrix elements
in the experimentally allowed/favoured ranges.Comment: 35 pages, 29 (partly colour) figures. Some typos corrected, wording
of several paragraphs improved, version accepted by Nucl. Phys.
Odd Chern-Simons Theory, Lie Algebra Cohomology and Characteristic Classes
We investigate the generic 3D topological field theory within AKSZ-BV
framework. We use the Batalin-Vilkovisky (BV) formalism to construct explicitly
cocycles of the Lie algebra of formal Hamiltonian vector fields and we argue
that the perturbative partition function gives rise to secondary characteristic
classes. We investigate a toy model which is an odd analogue of Chern-Simons
theory, and we give some explicit computation of two point functions and show
that its perturbation theory is identical to the Chern-Simons theory. We give
concrete example of the homomorphism taking Lie algebra cocycles to
Q-characteristic classes, and we reinterpreted the Rozansky-Witten model in
this light.Comment: 52 page
Chern-Simons action for inhomogeneous Virasoro group as an extension of three dimensional flat gravity
We initiate the study of a Chern-Simons action associated to the semi-direct
sum of the Virasoro algebra with its coadjoint representation. This model
extends the standard Chern-Simons formulation of three dimensional flat gravity
and is similar to the higher-spin extension of three dimensional anti-de Sitter
or flat gravity. The extension can also be constructed for the exotic but not
for the cosmological constant deformation of flat gravity.Comment: 15 pages. Version to appear in J. of Math. Phy
Critical behavior of a cellular automaton highway traffic model
We derive the critical behavior of a CA traffic flow model using an order
parameter breaking the symmetry of the jam-free phase. Random braking appears
to be the symmetry-breaking field conjugate to the order parameter. For
, we determine the values of the critical exponents ,
and using an order-3 cluster approximation and computer
simulations. These critical exponents satisfy a scaling relation, which can be
derived assuming that the order parameter is a generalized homogeneous function
of and p in the vicinity of the phase transition point.Comment: 6 pages, 12 figure
George Engel's Epistemology of Clinical Practice.
George Engel's (1913-1999) biopsychosocial model, one of the most significant proposals for the renewal of medicine in the latter half of the 20th century, has been understood primarily as a multi-factorial approach to the etiology of disease and as a call to re-humanize clinical practice. This common reading of Engel's model misses the central aspect of his proposal, that the biopsychosocial model is an epistemology for clinical work. By stating the simple fact that the clinician is not dealing directly with a body, but first, and inevitably, with a person, Engel challenged the epistemology implicit in the classical clinical method-a method predicated on the possibility of direct access to the body. Framed in epistemological terms, the issue at stake is not the need to complement medical science with humane virtues, but rather to acknowledge that the object of clinical practice is not the body but the patient
Graded Differential Geometry of Graded Matrix Algebras
We study the graded derivation-based noncommutative differential geometry of
the -graded algebra of complex -matrices
with the ``usual block matrix grading'' (for ). Beside the
(infinite-dimensional) algebra of graded forms the graded Cartan calculus,
graded symplectic structure, graded vector bundles, graded connections and
curvature are introduced and investigated. In particular we prove the
universality of the graded derivation-based first-order differential calculus
and show, that is a ``noncommutative graded manifold'' in a
stricter sense: There is a natural body map and the cohomologies of and its body coincide (as in the case of ordinary graded manifolds).Comment: 21 pages, LATE
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