14,567 research outputs found
Conics in normed planes
We study the generalized analogues of conics for normed planes by using the
following natural approach: It is well known that there are different metrical
definitions of conics in the Euclidean plane. We investigate how these
definitions extend to normed planes, and we show that in this more general
framework these different definitions yield, in almost all cases, different
classes of curves.Comment: 12 pages, 8 figure
Neutrino quasielastic interaction and nuclear dynamics
We investigate the double differential neutrino-carbon quasielastic cross
sections as measured by the MiniBooNE experiment. Our present treatment
incorporates relativistic corrections in the nuclear response functions and
includes the multinucleon component. We confirm our previous conclusion that it
is possible to account for all the data without any modification of the axial
mass. We also introduce the Q^2 distribution for charged and neutral current.
The data point at a sizable multinucleon component beside the genuine
quasielastic peak. They are also indicative of the collective character of the
nuclear response, of interest for hadronic physics.Comment: Two figures added and two figures modifie
Energy reconstruction effects in neutrino oscillation experiments and implications for the analysis
Data on neutrino oscillation often involve reconstructed neutrino energies
while the analysis implies the real neutrino energy. The corrections
corresponding to the transformation from real to reconstructed energy are
discussed in the case of Cherenkov detectors where multinucleon events appear
as quasielastic ones. These corrections show up as a tendency for the events to
escape the region of high flux, with a clear preference for the low energy
side. This is an effect of the multinucleon component of the quasielastic cross
section. We have applied our corrections to the T2K and MiniBooNE data for
electron appearance or disappearance data. We show that the inclusion
of this correction in the analysis is expected to lead to an increase of the
best fit oscillation mass parameters, particularly pronounced for the MiniBooNE
neutrino data. This inclusion in the analysis of the MiniBooNE neutrino data
should improve the compatibility with the existing constraints
Neutrino energy reconstruction problems and neutrino oscillations
We discuss the accuracy of the usual procedure for neutrino energy
reconstruction which is based on the quasielastic kinematics. Our results are
described in terms of a probability distribution for a real neutrino energy
value. Several factors are responsible of the deviations from the reconstructed
value. The main one is the multinucleon component of the neutrino interaction
which in the case of Cherenkov detectors enters as a quasielastic cross
section, increasing the mean neutrino energy which can differ appreciably from
the reconstructed value. As an application we derive, for excess electron
events attributed to the conversion of muon neutrinos, the true neutrino energy
distribution based on the experimental one which is given in terms of the
reconstructed value. The result is a reshaping effect. For MiniBooNE the low
energy peak is suppressed and shifted at higher energies, which may influence
the interpretation in terms of oscillation. For T2K at the Super Kamiokande far
detector the reshaping translates into a narrowing of the energy distribution
The effects of upcoding, cream skimming and readmissions on the Italian hospitals efficiency: a populationâbased investigation
In this paper we analyze the effects of some distortions induced by prospective payment system, i.e. Upcoding, Cream Skimming and Readmissions, on hospitalsâ technical efficiency. We estimate a production function using a populationâbased dataset composed by all active hospitals in an Italian region during the period 1998â2007. We show that cream skimming and upcoding have a negative impact on hospitalsâ technical efficiency, while readmissions have a positive effect. Moreover, we find that private hospitals are more engaged in cream skimming than public and notâforâprofit ones, while we observe no ownership differences regarding upcoding. Notâforâprofit hospitals have the highest readmission index. Last, notâforâprofit and public hospitals have the same efficiency levels, while private hospitals have the lowest technical efficiency.Upcoding, Cream Skimming, Readmission, Hospital Technical Efficiency, Ownership.
Exact Solution for the Protected TEM edge mode in a PTD-Symmetric Parallel-Plate Waveguide
A Parity Time-reversal Dual (PTD) symmetric structure constituted by a
Perfectly-Electric-Perfectly magnetic (PEC-PMC) parallel plate waveguide (PPW)
is analyzed. This waveguide supports unimodal transverse electromagnetic (TEM)
edge mode propagation protected against back-scattering from a certain class of
deformations and defects. The TEM solution is found in analytical form by using
three different methods, namely conformal mapping, mode-matching, and
Fourier-transform methods. It is shown through numerical simulations that the
mode propagation is robust with respect to deformations such as 90{\deg} bends
and discontinuity such as transition to free-space. Implementation of the PMC
boundary conditions via both a bed of nails and a mushroom structure is also
successfully investigated
Neutrino and antineutrino quasielastic interactions with nuclei
We investigate the interaction of neutrinos and antineutrinos with nuclei. We
explore in particular the role played by the multinucleon excitations which can
contaminate the quasielastic cross section. For neutrinos the multinucleon term
produces a sizable increase of the quasielastic cross section. Part of the
effect arises from tensor correlations. For antineutrinos this influence is
smaller owing to the axial-vector interference which increases the relative
importance of the terms which are not affected by these multinucleon
excitations
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