Search results for "parity"
showing 10 items of 513 documents
Revealing non-classical behaviours in the oscillatory motion of a trapped ion
2003
The possibility of revealing non-classical behaviours in the dynamics of a trapped ion via measurements of the mean value of suitable operators is reported. In particular we focus on the manifestation known as `` Parity Effect\rq\rq which may be observed \emph{directly measuring} the expectation value of an appropriate correlation operator. The experimental feasibility of our proposal is discussed.
New constraints on axion-mediated P , T -violating interaction from electric dipole moments of diamagnetic atoms
2018
The exchange of an axionlike particle between atomic electrons and the nucleus may induce electric dipole moments (EDMs) of atoms and molecules. This interaction is described by a parity- and time-reversal-invariance-violating potential which depends on the product of a scalar ${g}^{s}$ and a pseudoscalar ${g}^{p}$ coupling constant. We consider the interaction with the specific combination of these constants, ${g}_{e}^{s}{g}_{N}^{p}$, which gives significant contributions to the EDMs of diamagnetic atoms. In this paper, we calculate these contributions to the EDMs of $^{199}\mathrm{Hg}$, $^{129}\mathrm{Xe}$, $^{211}\mathrm{Rn}$, and $^{225}\mathrm{Ra}$ for a wide range of axion masses. Com…
Low-lying shears bands in very light odd—odd Bi isotopes
2003
The concept of magnetic rotation in nuclei was introduced to explain the observed regular bands with enhanced M1 transitions and weak or absent E2 crossover transitions in nearly spherical nuclei around 198Pb [1]. These bands can be described by the coupling of high-j proton and neutron configurations to a total spin tilted at an angle of ~ 45° with respect to the symmetry axis. As the proton and neutron spins align with increasing excitation energy, a sequence of ΔI = 1 levels of fixed parity (“shears band”) is formed [2].
Monetary Policy and the Exchange Rate During the Asian Crisis: Identification Through Heteroscedasticity
2003
This paper examines whether a monetary policy tightening (i.e., an increase in the domestic interest rate) was successful in defending the exchange rate from speculative pressures during the Asian financial crisis. We estimate a bivariate VECM for four Asian countries, and improve upon existing studies in two important ways. First, by using a long data span we are able to compare the effects of an interest rate rise on the nominal exchange rate during tranquil and turbulent periods. Second, we take into account the endogeneity of interest rates and identify the system by exploiting the heteroscedasticity properties of the relevant time series, following Rigobon (2002). We find that while ti…
Heavy-quark spin symmetry for charmed and strange baryon resonances
2013
We study charmed and strange odd-parity baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channels model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor symmetry plus a suitable symmetry breaking. The model generates resonances with negative parity from the s-wave interaction of pseudoscalar and vector mesons with 1/2(+) and 3/2(+) baryons in all the isospin, spin, and strange sectors with one, two, and three charm units. Some of our results can be identified with experimental data from several facilities, such as the CLEO, Belle, or BaBar Collaborations, as we…
Generating restricted classes of involutions, Bell and Stirling permutations
2010
AbstractWe present a recursive generating algorithm for unrestricted permutations which is based on both the decomposition of a permutation as a product of transpositions and that as a union of disjoint cycles. It generates permutations at each recursive step and slight modifications of it produce generating algorithms for Bell permutations and involutions. Further refinements yield algorithms for these classes of permutations subject to additional restrictions: a given number of cycles or/and fixed points. We obtain, as particular cases, generating algorithms for permutations counted by the Stirling numbers of the first and second kind, even permutations, fixed-point-free involutions and d…
Computing the Probability for Data Loss in Two-Dimensional Parity RAIDs
2017
Parity RAIDs are used to protect storage systems against disk failures. The idea is to add redundancy to the system by storing the parity of subsets of disks on extra parity disks. A simple two-dimensional scheme is the one in which the data disks are arranged in a rectangular grid, and every row and column is extended by one disk which stores the parity of it.In this paper we describe several two-dimensional parity RAIDs and analyse, for each of them, the probability for dataloss given that f random disks fail. This probability can be used to determine the overall probability using the model of Hafner and Rao. We reduce subsets of the forest counting problem to the different cases and show…
L'équité : un fil rouge des politiques éducatives nationales
2014
This paper aims to cover some at least of the most significant dimensions that can help document, based on a sampling of countries, the issues surrounding equity and children's right to attend school, to stay in school long enough and to receive appropriate education services to ensure access to adult life with the basic knowledge and skills that will give them a chance at a decent economic and social life. Above and beyond its quantitative observations, this analysis identifies connections with various active or passive education policies found in national education systems. Additionally,to the extent that they provide a better understanding of the situation and point out stumbling blocks …
New Evidence of the Real Interest Rate Parity for OECD Countries Using Panel Unit Root Tests with Breaks
2006
This paper tests for real interest parity (RIRP) among the nineteen major OECD countries over the period 1978:Q2-1998:Q4. The econometric methods applied consist of combining the use of several unit root or stationarity tests designed for panels valid under cross-section dependence and presence of multiple structural breaks. Our results strongly support the fulfillment of the weak version of the RIRP for the studied period once dependence and structural breaks are accounted for.
- EL EFECTO FISHER Y LA PARIDAD DE INTERÉS REAL. EVIDENCIA PARA LA ECONOMÍA ESPAÑOLA
1999
This paper provides an empirical test of the Fisher effect and of the real interest parity. The objetive is to determinate the behavior of the ex-ante real interest that condicionate the intertemporal savings and investment decisions. The method used is the time series properties of the data, which allows to separate estimation of the long-run equilibrium relationship from the nuisance parameters that characterize the short-run dynamics. The results find support inthe long run for a tax-adjusted Fisher hypothesis but not for the real interest parity. En este trabajo se contrasta empíricamente el cumplimiento de la hipótesis de Fisher y de la paridad de interés real para el caso español. El …