Search results for "Statistics::Applications"
showing 10 items of 24 documents
Measurement of the W boson mass
1996
The W boson mass is measured using proton-proton collision data at root s = 13 TeV corresponding to an integrated luminosity of 1.7fb(-1) recorded during 2016 by the LHCb experiment. With a simultaneous fit of the muon q/p(T) distribution of a sample of W ->mu y decays and the phi* distribution of a sample of Z -> mu mu decays the W boson mass is determined to be
Fixed Points for Multivalued Convex Contractions on Nadler Sense Types in a Geodesic Metric Space
2019
In 1969, based on the concept of the Hausdorff metric, Nadler Jr. introduced the notion of multivalued contractions. He demonstrated that, in a complete metric space, a multivalued contraction possesses a fixed point. Later on, Nadler&rsquo
Imputation Procedures in Surveys Using Nonparametric and Machine Learning Methods: An Empirical Comparison
2020
Abstract Nonparametric and machine learning methods are flexible methods for obtaining accurate predictions. Nowadays, data sets with a large number of predictors and complex structures are fairly common. In the presence of item nonresponse, nonparametric and machine learning procedures may thus provide a useful alternative to traditional imputation procedures for deriving a set of imputed values used next for the estimation of study parameters defined as solution of population estimating equation. In this paper, we conduct an extensive empirical investigation that compares a number of imputation procedures in terms of bias and efficiency in a wide variety of settings, including high-dimens…
Hybridization ofsd- andfp-shell proton orbitals in the systemS36+37Cl
1993
Experimental and theoretical evidence is presented that the proton exchange is strongly enhanced by a mixing of single-particle configurations in $^{37}\mathrm{Cl}$ (in the system $^{36}\mathrm{S}$${+}^{37}$Cl, which is shown to be the clearest example of hybridization in nuclear physics. The experimental data on elastic and inelastic transfer are only reproduced if the complete set of single-particle states (${\mathit{d}}_{3/2}$,${\mathit{s}}_{1/2}$,${\mathit{f}}_{7/2}$,${\mathit{p}}_{3/2}$,${\mathit{f}}_{5/2}$, and ${\mathit{p}}_{1/2}$) is included in a coupled-reaction-channel calculation. The strong enhancement is explained by the hybridization of orbits of different parity. In a two-ce…
A characterization of absolutely summing operators by means of McShane integrable functions
2004
AbstractAbsolutely summing operators between Banach spaces are characterized by means of McShane integrable functions.
Equivalence betweenXYand dimerized models
2010
The spin-$1/2$ chain with $\mathit{XY}$ anisotropic coupling in the plane and the $\mathit{XX}$ isotropic dimerized chain are shown to be equivalent in the bulk. For finite systems, we prove that the equivalence is exact in given parity sectors, after taking care of the precise boundary conditions. The proof is given constructively by finding unitary transformations that map the models onto each other. Moreover, we considerably generalized our mapping and showed that even in the case of fully site-dependent couplings the $\mathit{XY}$ chain can be mapped onto an $\mathit{XX}$ model. This result has potential application in the study of disordered systems.
Radiative kaon capture on nuclei.
1990
Hypernuclear formation through the radiative capture of in-flight ${\mathit{K}}^{\mathrm{\ensuremath{-}}}$ is studied in a distorted wave impluse approximation approach. The elementary operator is obtained from first-order Feynman diagrams and is constrained by the reactions ${\mathit{K}}^{\mathrm{\ensuremath{-}}}$p\ensuremath{\rightarrow}\ensuremath{\Lambda}\ensuremath{\gamma} and, via crossing, by \ensuremath{\gamma}p\ensuremath{\rightarrow}${\mathit{K}}^{+}$\ensuremath{\Lambda}. The ${\mathit{K}}^{\mathrm{\ensuremath{-}}}$ distortion has been included via a simple optical potential which is in agreement with ${\mathit{K}}^{\mathrm{\ensuremath{-}}}$ elastic scattering on nuclei. Using the…
Constraints on Coupling Constants through Charged $\Sigma$ Photoproduction
1995
The few available data for the reactions $\gamma p \rightarrow K^{0} \Sigma^{+}$ and $\gamma n \rightarrow K^{+} \Sigma^{-}$ are compared to models developed for the processes $\gamma p \rightarrow K^{+} \Sigma^{0}$ and $\gamma p \rightarrow K^{+} \Lambda$. It is found that some of these phenomenological models overpredict the measurements by up to a factor of 100. Fitting the data for all of these reactions leads to drastically reduced Born coupling constants.
Mass singularities in light quark correlators: the strange quark case
1995
The correlators of light-quark currents contain mass-singularities of the form log(m^2/Q^2). It has been known for quite some time that these mass- logarithms can be absorbed into the vacuum expectation values of other operators of appropriate dimension, provided that schemes without normal- ordering are used. We discuss in detail this procedure for the case of the mass logarithms m^4 log(m^2/Q^2), including also the mixing with the other dimension-4 operators to two-loop order. As an application we present an improved QCD sum rule determination of the strange-quark mass. We obtain m_s(1 GeV)=171 \pm 15 MeV.
Thin Ising films with competing walls: A Monte Carlo study.
1995
Ising magnets with a nearest neighbor ferromagnetic exchange interaction J on a simple cubic lattice are studied in a thin film geometry using extensive Monte Carlo simulations. The system has two large L\ifmmode\times\else\texttimes\fi{}L parallel free surfaces, a distance D apart from each other, at which competing surface fields act, i.e., ${\mathit{H}}_{\mathit{D}}$=-${\mathit{H}}_{1}$. In this geometry, the phase transition occurring in the bulk at a temperature ${\mathit{T}}_{\mathit{c}\mathit{b}}$ is suppressed, and instead one observes the gradual formation of an interface between coexisting phases stabilized by the surface fields. While this interface is located in the center of th…