16,123 research outputs found
Physics Signatures at CLIC
A set of signatures for physics processes of potential interests for the CLIC
programme at 1 - 5 TeV are discussed. These signatures, that may correspond to
the manifestation of different scenarios of new physics as well to Standard
Model precision tests, are proposed as benchmarks for the optimisation of the
CLIC accelerator parameters and for a first definition of the required detector
response.Comment: 15 pages, 10 figure
Detecting chaos in particle accelerators through the frequency map analysis method
The motion of beams in particle accelerators is dominated by a plethora of
non-linear effects which can enhance chaotic motion and limit their
performance. The application of advanced non-linear dynamics methods for
detecting and correcting these effects and thereby increasing the region of
beam stability plays an essential role during the accelerator design phase but
also their operation. After describing the nature of non-linear effects and
their impact on performance parameters of different particle accelerator
categories, the theory of non-linear particle motion is outlined. The recent
developments on the methods employed for the analysis of chaotic beam motion
are detailed. In particular, the ability of the frequency map analysis method
to detect chaotic motion and guide the correction of non-linear effects is
demonstrated in particle tracking simulations but also experimental data.Comment: Submitted for publication in Chaos, Focus Issue: Chaos Detection
Methods and Predictabilit
Review of Linac-Ring Type Collider Proposals
There are three possibly types of particle colliders schemes: familiar (well
known) ring-ring colliders, less familiar however sufficiently advanced linear
colliders and less familiar and less advanced linac-ring type colliders. The
aim of this paper is two-fold: to present possibly complete list of papers on
linac-ring type collider proposals and to emphasize the role of linac-ring type
machines for future HEP research.Comment: quality of figures is improved, some misprints are correcte
The Heliosphere---Blowing in the Interstellar Wind
Measurements of the velocity of interstellar HeI inside of the heliosphere
have been conducted over the past forty years. These historical data suggest
that the ecliptic longitude of the direction of the interstellar flow has
increased at an average rate of about 0.19 degrees per year over time. Possible
astronomical explanations for these short-term variations in the interstellar
gas entering the heliosphere are presented.Comment: Accepted for the proceedings of Solar Wind 1
A Study of e+e- -> H0A0 -> bbbb at 3 TeV at CLIC
The precise determination of the masses of the CP-odd and -even heavy Higgs
bosons is an important part of the study of Supersymmetry and its relation with
cosmology through dark matter. This note presents a determination of the A0
boson mass with the e+e- -> H0A0 -> b b b b process for a dark matter motivated
cMSSM scenario with M(A) = 1141 GeV at CLIC. The analysis is performed with
full simulation and reconstruction at 3 TeV accounting for beamstrahlung
effects. SM and SUSY backgrounds are considered and the effect of the overlay
of gamma gamma -> hadrons events on the signal is studied for various
assumptions for the detector time-stamping capabilities. The di-jet mass
resolution is improved by applying a kinematic fit. The A0 mass can be
determined with a statistical accuracy of ~3-5 GeV for 3 inverse ab of
statistics and 0 to 20 bunch crossings of gamma gamma background integrated in
one event, respectively.Comment: 11 pages, 4 figure
Probe of anomalous quartic couplings in the photon-photon collisions
In this paper, we examine the potentials of the processes and at the CLIC with
and TeV to investigate anomalous quartic
couplings by two different CP-violating and CP-conserving effective
Lagrangians. We find confidence level limits on the anomalous coupling
parameters at the three CLIC energies and various integrated luminosities. The
best limits obtained from the process
on the anomalous ,
and couplings
defined by CP-conserving effective Lagrangians are GeV, and GeV, while coupling
determined by CP-violating effective Lagrangians is obtained as GeV. In addition, the best limits derived on
, and
and from the
process are obtained as
GeV, GeV, and GeV, respectively.Comment: 33 pages, 27 figures, 4 tables, version to appear in JHE
Signs of heavy Higgs bosons at CLIC: An road to the Electroweak Phase Transition
We analyse the sensitivity of the proposed Compact Linear Collider (CLIC) to
the existence of beyond the Standard Model (SM) Higgs bosons through their
decays into pairs of massive gauge bosons and SM-like Higgses , considering CLIC centre of mass energies TeV and TeV.
We find that resonant di-Higgs searches at CLIC would allow for up to two
orders of magnitude improvement w.r.t. the sensitivity achievable by HL-LHC in
the mass range . Focusing then
on a real singlet extension of the SM, we explore the prospects of heavy Higgs
searches at CLIC for probing the regions of parameter space yielding a strongly
first order electroweak phase transition that could generate the observed
matter-antimatter asymmetry of the Universe. Our study illustrates the
complementarity between CLIC and other possible future colliders like FCC-ee in
probing singlet extensions of the SM, and shows that high-energy
colliders provide a powerful means to unravel the nature of electroweak
symmetry breaking in the early Universe.Comment: 27 pages, 15 figure
Fatigue resistance of new and used nickel-titanium rotary instruments: a comparative study
Aim of the present study was twofold. First, to evaluate in vitro, the performance of two different NiTi rotary instruments in one molar case; then, to evaluate their resistance to cyclic fatigue, compared to new ones
Statistical Modeling of Spatial Extremes
The areal modeling of the extremes of a natural process such as rainfall or
temperature is important in environmental statistics; for example,
understanding extreme areal rainfall is crucial in flood protection. This
article reviews recent progress in the statistical modeling of spatial
extremes, starting with sketches of the necessary elements of extreme value
statistics and geostatistics. The main types of statistical models thus far
proposed, based on latent variables, on copulas and on spatial max-stable
processes, are described and then are compared by application to a data set on
rainfall in Switzerland. Whereas latent variable modeling allows a better fit
to marginal distributions, it fits the joint distributions of extremes poorly,
so appropriately-chosen copula or max-stable models seem essential for
successful spatial modeling of extremes.Comment: Published in at http://dx.doi.org/10.1214/11-STS376 the Statistical
Science (http://www.imstat.org/sts/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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