234 research outputs found
Study of Extra Space Dimensions in Vector Boson Pair Production at LEP
Recent theoretical scenarios propose that quantum gravity effects may
manifest at LEP energies by means of gravitons that couple to Standard Model
particles and propagate into extra space dimensions. These predictions are
checked against the most recent experimental results on photon, W and Z pair
production. No deviations from the Standard Model expectations are found and
limits of the order of 1 TeV on the scale of these models are set.Comment: 6 pages, 1 figur
Determining highway corridors
In the highway development process, the first planning stage is that of selecting a corridor along which the highway is to pass. Highway corridor selection represents a multicriteria decision process in which a variety of social, enviromental and economic factors must be evaluated and weighted for a large number of corridor alternatives. This paper proposes a demand-based approach to provide a set of potential corridors. The problem is formulated as a continuous location model which seeks a set of optimal corridors with respect to the demand of potential users while satisfying budget constraints. This model uses geographical information in order to estimate the length-dependent costs (such as pavement and construction cost) and the cost of earth movement. A procedure for finding the best local minima of the optimization model is proposed. This method is tested using the Particle Swarm Optimization algorithm, two algorithms of the Simulated Annealing type and the Simplex Nedelmar method. An application using the Castilla-La Mancha\s geographic database is presented
Primordial non-Gaussianity with Angular correlation function: Integral constraint and validation for DES
Local primordial non-Gaussianity (PNG) is a promising observable of the
underlying physics of inflation, characterised by . We
present the methodology to measure from the Dark Energy
Survey (DES) data using the 2-point angular correlation function (ACF) with
scale-dependent bias. One of the focuses of the work is the integral
constraint. This condition appears when estimating the mean number density of
galaxies from the data and is key in obtaining unbiased
constraints. The methods are analysed for two types of simulations:
GOLIAT-PNG N-body small area simulations with equal to -100 and
100, and 1952 Gaussian ICE-COLA mocks with that follow the DES
angular and redshift distribution. We use the ensemble of GOLIAT-PNG mocks to
show the importance of the integral constraint when measuring PNG, where we
recover the fiducial values of within the when including
the integral constraint. In contrast, we found a bias of when not including it. For a DES-like scenario, we forecast a bias of
, equivalent to , when not using the IC
for a fiducial value of . We use the ICE-COLA mocks to validate
our analysis in a realistic DES-like setup finding it robust to different
analysis choices: best-fit estimator, the effect of IC, BAO damping,
covariance, and scale choices. We forecast a measurement of within
when using the DES-Y3 BAO sample, with the ACF in the
range.Comment: Version after MNRAS reviewer comments. Improved discussion in Section
7. 16 pages, 11 figure
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