What is the physical meaning of the AE index?

Y. Kamide; G. Rostoker

doi:10.1029/2004eo190010

On the existence and physical meaning of the Zenneck wave

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0179.200907j.0801 ◽

2009 ◽

Vol 179 (7) ◽

pp. 801 ◽

Cited By ~ 9

Author(s):

Aleksandr V. Kukushkin

Keyword(s):

Physical Meaning

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Seeking the Good Fitting Procedure of PALS Polymer Spectra

Materials Science Forum ◽

10.4028/www.scientific.net/msf.607.64 ◽

2008 ◽

Vol 607 ◽

pp. 64-66

Author(s):

Nicolas Laforest ◽

Jérémie De Baerdemaeker ◽

Corine Bas ◽

Charles Dauwe

Keyword(s):

Experimental Data ◽

Low Temperature ◽

Positron Annihilation ◽

Physical Meaning ◽

Lifetime Measurements ◽

Positron Annihilation Lifetime ◽

Fitting Procedure ◽

Fitting Procedures ◽

Blob Model

Positron annihilation lifetime measurements on polymethylmethacrylate (PMMA) at low temperature were performed. Different discrete fitting procedures have been used to analyze the experimental data. It shows that the extracted parameters depend strongly on the fitting procedure. The physical meaning of the results is discussed. The blob model seems to give the best annihilation parameters.

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Hamiltonian charges in the asymptotically de Sitter spacetimes

Journal of High Energy Physics ◽

10.1007/jhep05(2021)063 ◽

2021 ◽

Vol 2021 (5) ◽

Author(s):

Maciej Kolanowski ◽

Jerzy Lewandowski

Keyword(s):

Phase Space ◽

Initial Data ◽

Exact Solutions ◽

Gravitational Waves ◽

Physical Meaning ◽

De Sitter ◽

Killing Vectors ◽

Asymptotically Flat ◽

Angular Momenta ◽

The One

Abstract We generalize a notion of ‘conserved’ charges given by Wald and Zoupas to the asymptotically de Sitter spacetimes. Surprisingly, our construction is less ambiguous than the one encountered in the asymptotically flat context. An expansion around exact solutions possessing Killing vectors provides their physical meaning. In particular, we discuss a question of how to define energy and angular momenta of gravitational waves propagating on Kottler and Carter backgrounds. We show that obtained expressions have a correct limit as Λ → 0. We also comment on the relation between this approach and the one based on the canonical phase space of initial data at ℐ+.

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Physical meaning of temperature in superstatistics

EPL (Europhysics Letters) ◽

10.1209/0295-5075/130/30005 ◽

2020 ◽

Vol 130 (3) ◽

pp. 30005

Author(s):

E. Gravanis ◽

E. Akylas ◽

G. Livadiotis

Keyword(s):

Physical Meaning

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Nonlinear analysis of magnetospheric data Part I. Geometric characteristics of the AE index time series and comparison with nonlinear surrogate data

Nonlinear Processes in Geophysics ◽

10.5194/npg-6-51-1999 ◽

1999 ◽

Vol 6 (1) ◽

pp. 51-65 ◽

Cited By ~ 23

Author(s):

G. P. Pavlos ◽

M. A. Athanasiu ◽

D. Kugiumtzis ◽

N. Hatzigeorgiu ◽

A. G. Rigas ◽

...

Keyword(s):

Time Series ◽

State Space ◽

Null Hypothesis ◽

Surrogate Data ◽

Statistical Testing ◽

Geometrical Parameters ◽

Geometric Characteristics ◽

Geometrical Characteristics ◽

Ae Index ◽

Index Time Series

Abstract. A long AE index time series is used as a crucial magnetospheric quantity in order to study the underlying dynainics. For this purpose we utilize methods of nonlinear and chaotic analysis of time series. Two basic components of this analysis are the reconstruction of the experimental tiine series state space trajectory of the underlying process and the statistical testing of an null hypothesis. The null hypothesis against which the experimental time series are tested is that the observed AE index signal is generated by a linear stochastic signal possibly perturbed by a static nonlinear distortion. As dis ' ' ating statistics we use geometrical characteristics of the reconstructed state space (Part I, which is the work of this paper) and dynamical characteristics (Part II, which is the work a separate paper), and "nonlinear" surrogate data, generated by two different techniques which can mimic the original (AE index) signal. lie null hypothesis is tested for geometrical characteristics which are the dimension of the reconstructed trajectory and some new geometrical parameters introduced in this work for the efficient discrimination between the nonlinear stochastic surrogate data and the AE index. Finally, the estimated geometric characteristics of the magnetospheric AE index present new evidence about the nonlinear and low dimensional character of the underlying magnetospheric dynamics for the AE index.

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