Search results for "PARITY"
showing 10 items of 513 documents
Anisotropy-Induced Effects in the Dynamics of an Ion Confined in a Two-Dimensional Paul Trap
2006
We investigate the role of anisotropy in the dynamics of a single trapped ion interacting with two orthogonal laser beams, considering how it modifies a scheme for the generation of Schrödinger cat states and the so called parity effect in two-dimensional isotropic Paul traps. We find that anisotropy gives rise to a richer class for the generated states and to a larger number of observables sensitive to the parity of the number of excitation of the vibrational motion of the ion.
A segmented regression model for event history data: an application to the fertility patterns in Italy
2009
We propose a segmented discrete-time model for the analysis of event history data in demographic research. Through a unified regression framework, the model provides estimates of the effects of explanatory variables and jointly accommodates flexibly non-proportional differences via segmented relationships. The main appeal relies on ready availability of parameters, changepoints, and slopes, which may provide meaningful and intuitive information on the topic. Furthermore, specific linear constraints on the slopes may also be set to investigate particular patterns. We investigate the intervals between cohabitation and first childbirth and from first to second childbirth using individual data …
In-beam spectroscopic study of Cf244
2018
The ground-state rotational band of the neutron-deficient californium (Z = 98) isotope 244Cf was identified for the first time and measured up to a tentative spin and parity of I I-pi = 20(+). The observation of the rotational band indicates that the nucleus is deformed. The kinematic and dynamic moments of inertia were deduced from the measured gamma-ray transition energies. The behavior of the dynamic moment of inertia revealed an up-bend due to a possible alignment of coupled nucleons in high-j orbitals starting at a rotational frequency of about (h) over bar (omega) = 0.20 MeV. The results were compared with the systematic behavior of the even-even N = 146 isotones as well as with avail…
High precision quantum query algorithm for computing AND-based boolean functions
2010
Quantum algorithms can be analyzed in a query model to compute Boolean functions. Function input is provided in a black box, and the aim is to compute the function value using as few queries to the black box as possible. The complexity of the algorithm is measured by the number of queries on the worst-case input. In this paper we consider computing AND Boolean function. First, we present a quantum algorithm for AND of two bits. Our algorithm uses one quantum query and correct result is obtained with a probability p=4/5, that improves previous results. The main result is generalization of our approach to design efficient quantum algorithms for computing composite function AND(f1,f2) where fi…
Social Disparities in Education in Sub-Saharan African Countries
2007
In this paper we have two complementary objectives: the first is to describe the magnitude of social disparities that exist in the systems of education of sub-Saharan African countries; we focus on recent data but we also put these data in a time perspective. The second objective is to identify some of the factors that may explain these disparities and the impact of policies aimed at their reduction.
Bloch Modes Coupling in Photonic Crystal Waveguides
2005
We investigate the properties of Bloch modes inside a photonic crystal waveguide. By using simultaneously a near field optical microscope and a transmittance setup, we demonstrate that Bloch modes having different parity are coupled.
Assessment of spatial perception for a multi-layer volumetric display: the effect of exocentric and egocentric distance on relative depth judgements
2020
Three-dimensional images on multiple depth layers of the volumetric display provide the physiological depth cues which ensure the high precision of depth judgements at close viewing distances and enhance the user experience. However, the contribution of physiological cues declines with an increase of viewing distance (egocentric distance), and the human spatial perception varies depending on the inter-stimuli distance (exocentric distance). We conducted a psychophysical experiment to test the perception of three-dimensional images rendered on the volumetric display depending on exocentric and egocentric stimuli distance. The constant angular size visual stimuli were displayed on different d…
Sexual and reproductive traits of Hypania invalida (Polychaeta, Ampharetidae): a remarkable invasive species in Central European waterways
2010
SUMMARY 1. The Ponto-Caspian polychaete Hypania invalida (Archiv fur Naturgeschichte, 1860, 26, 109) is undergoing rapid range expansion in the Rhine and other central European waterways. We examined its reproductive traits in an attempt to account for its remarkable invasive success. 2. For the first time in this species, we found males, dioecy (gonochorism) and an exclusively sexual mode of reproduction; no indication for hermaphroditism or (unisexual) partheno- genesis, that could explain the rapid range expansion of H. invalida, was found. 3. Our experimental evidence shows that H. invalida reproduces by males discharging their sperm into the water column while eggs are retained and fer…
Isotopic variation of parity violation in atomic ytterbium: Description of the measurement method and analysis of systematic effects
2019
We present a detailed description of experimental studies of the parity violation effect in an isotopic chain of atomic ytterbium (Yb), whose results were reported in a recent paper [Antypas et al., Nat. Phys. 15, 120 (2019)]. We discuss the principle of these measurements, made on the Yb $6{s}^{2} {}^{1}{S}_{0}\ensuremath{\rightarrow}5d6s ^{3}D_{1}$ optical transition at 408 nm, describe the experimental apparatus, and give a detailed account of our studies of systematic effects in the experiment. Our results offer a direct observation of the isotopic variation in the atomic parity violation effect, a variation which is in agreement with the prediction of the standard model. These measurem…
The pure descent statistic on permutations
2017
International audience; We introduce a new statistic based on permutation descents which has a distribution given by the Stirling numbers of the first kind, i.e., with the same distribution as for the number of cycles in permutations. We study this statistic on the sets of permutations avoiding one pattern of length three by giving bivariate generating functions. As a consequence, new classes of permutations enumerated by the Motzkin numbers are obtained. Finally, we deduce results about the popularity of the pure descents in all these restricted sets. (C) 2017 Elsevier B.V. All rights reserved.