33,702 research outputs found
Magnetic Fields and Non-Local Transport in Laser Plasmas
The first Vlasov-Fokker-Planck simulations of nanosecond laser-plasma interactions
â including the effects of self-consistent magnetic fields and hydrodynamic
plasma expansion â will be presented. The coupling between non-locality and magnetic
field advection is elucidated. For the largest (initially uniform) magnetic fields
externally imposed in recent long-pulse laser gas-jet plasma experiments (12T) a significant
degree of cavitation of the B-field will be shown to occur (> 40%) in under
500ps. This is due to the Nernst effect and leads to the re-emergence of non-locality
even if the initial value of the magnetic field strength is sufficient to localize transport.
Classical transport theory may also break down in such interactions as a result of
inverse bremsstrahlung heating. Although non-locality may be suppressed by a large
B-field, inverse bremsstrahlung still leads to a highly distorted distribution. Indeed
the best fit for a 12T applied field (after 440ps of laser heating) is found to be a super-
Gaussian distribution â f0 α eâvm â with m = 3.4. The effects of such a distribution
on the transport properties under the influence of magnetic fields are elucidated in
the context of laser-plasmas for the first time.
In long pulse laser-plasma interactions magnetic fields generated by the thermoelectric
(ââne Ă âTeâ) mechanism are generally considered dominant. The strength
of B-fields generated by this mechanism are affected, and new generation mechanisms
are expected, when non-locality is important. Non-local B-field generation is found
to be dominant in the interaction of an elliptical laser spot with a nitrogen gas-jet
Innovation or a Race to the Bottom? Trust Modernization in New Hampshire
[Excerpt] âLate last summer, Governor Lynch signed into law Senate Bill 465, designed to further update New Hampshireâs trust law. This bill follows similar legislation in Alaska, Delaware, Nevada, and several other states. It adds major new provisions to the existing statutory framework for irrevocable trusts. The bill allows for the creation of so-called self-settled asset protection trusts or domestic asset protection trusts (DAPTs). DAPTs represent the latest chapter in our Stateâs move away from traditional trust and estate principles towards a system of dynastic and (theoretically) creditor-proof trusts.
This legislation results from New Hampshireâs desire to retain and attract trust activity. Effective January 2, 2009, the new Qualified Dispositions in Trust Act allows beneficiaries to âself settleâ irrevocable spendthrift trustsâfor example, put assets into trust for their own benefit, while placing those assets, in many circumstances, out of the reach of most creditors. This article will attempt to answer some questions about these trusts. Will RSA 564âD succeed in increasing New Hampshireâs share of the domestic trust business? Will these new trusts prove to be effective against creditors? Finally, what are the policy implications of these new trusts?
The Muted Vibrancy of Roman Catholicism in Contemporary Portugal: Corporal Works of Mercy in a Time of Austerity. CES Open Forum Series #25 2018-2019
This paper concerns the role and function of religious-based organizations in strengthening associational
life. Taking Portugal as a case study, it asks whether the concept of muted vibrancy
provides theoretical understanding to the role of Catholicism in contemporary Portuguese society.
That is, how might a church in a newly consolidated democratic regime, in a time of economic
crisis, with a past relationship to a fascist regime, and with declining numbers of
adherents, contribute to the deepening of democracy
Complementarity and uncertainty in Mach-Zehnder interferometry and beyond
A coherent account of the connections and contrasts between the principles of complementarity and uncertainty is developed starting from a survey of the various formalizations of these principles. The conceptual analysis is illustrated by means of a set of experimental schemes based on Mach-Zehnder interferometry. In particular, path detection via entanglement with a probe system and (quantitative) quantum erasure are exhibited to constitute instances of joint unsharp, measurements of complementary pairs of physical quantities, path and interference observables. The analysis uses the representation of observables as positive-operator-valued measures (POVMs). The reconciliation of complementary experimental options in the sense of simultaneous unsharp preparations and measurements is expressed in terms of uncertainty relations of different kinds. The feature of complementarity, manifest in the present examples in the mutual exclusivity of path detection and interference observation, is recovered as a limit case from the appropriate uncertainty relation. It is noted that the complementarity and uncertainty principles are neither completely logically independent nor logical consequences of one another. Since entanglement is an instance of the uncertainty of quantum properties (of compound systems), it is moot to play out uncertainty and entanglement against each other as possible mechanisms enforcing complementarity. (c) 2006 Published by Elsevier B.V
Atmospheric effects and spurious signals in GPS analyses
Improvements in the analyses of Global Positioning System (GPS) observations yield resolvable millimeter to submillimeter differences in coordinate estimates, thus providing sufficient resolution to distinguish subtle differences in analysis methodologies. Here we investigate the effects on site coordinates of using different approaches to modeling atmospheric loading deformation (ATML) and handling of tropospheric delays. The rigorous approach of using the time-varying Vienna Mapping Function 1 yields solutions with lower noise at a range of frequencies compared with solutions generated using empirical mapping functions. This is particularly evident when ATML is accounted for. Some improvement also arises from using improved a priori zenith hydrostatic delays (ZHD), with the combined effect being site-specific. Importantly, inadequacies in both mapping functions and a priori ZHDs not only introduce time-correlated noise but significant periodic terms at solar annual and semiannual periods. We find no significant difference between solutions where nontidal ATML is applied at the observation level rather than as a daily averaged value, but failing to model diurnal and semidiurnal tidal ATML at the observation level can introduce anomalous propagated signals with periods that closely match the GPS draconitic annual (âŒ351.4 days) and semiannual period (âŒ175.7 days). Exacerbated by not fixing ambiguities, these signals are evident in both stacked and single-site power spectra, with each tide contributing roughly equally to the dominant semiannual peak. The amplitude of the propagated signal reaches a maximum of 0.8 mm with a clear latitudinal dependence that is not correlated directly with locations of maximum tidal amplitude.Australian Research Councilâs Discovery Project
Reconsidering Economic Relations and Political Citizenship in the New Iberia of the New Europe: Some Lessons from the Fifteenth Anniversary of the Accession of Portugal and Spain to the European Union. CES Working Paper, no. 94, 2003
The purpose of this paper is to use the fifteenth anniversary of the accession of Portugal and Spain to the European Union as an opportunity to reflect on what has happened to both countries since 1986. It examines the integration process and how it has affected political, economic and social developments in Portugal and in Spain over the last fifteen years. In our view, and on balance, Spain and Portugal have benefited from accession. Since the last century, the obsession of Spanish and Portuguese reformists has been to make up the lost ground with modernized Europe. EU membership has been a critical step in this direction. The record of the past fifteen years is that this dream is becoming an economic reality. Despite impressive achievements, however, namely, since 1986, Portugalâs average per capita income has grown from 56 percent of the EU average to about 74 percent, whereas Spainâs has grown to 83 percentâboth Iberian countries still have a long way to go to reach the EU average wealth. In addition, the question of Iberian and/or European citizenship, and its impact on the Portuguese and Spanish, remains open
Technical trading rules in the European Monetary System
Using the genetic programming methodology developed in Neely, Weller and Dittmar (1997), we find trading rules that generate significant excess returns for three of four EMS exchange rates over the out-of-sample period 1986-1996. Permitting the rules to use information about the interest rate differential proved to be important. The reduction in volatility resulting from the imposition of a narrower band may reduce trading rule profitability. The currency for which there was least evidence of significant excess returns was the Dutch guilder, which was also the only currency that remained within a band of 2.25% throughout our sample period. Our results cannot be duplicated by the moving average or filter rules commonly used by technical analysts or by two trading rules designed specifically to exploit known features of target zone exchange rates. The observed excess returns cannot be explained as compensation for bearing systematic risk.Foreign exchange ; European Monetary System (Organization)
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