165 research outputs found
Discrete Symmetries and Generalized Fields of Dyons
We have studied the different symmetric properties of the generalized
Maxwell's - Dirac equation along with their quantum properties. Applying the
parity (\mathcal{P}), time reversal (\mathcal{T}), charge conjugation
(\mathcal{C}) and their combined effect like parity time reversal
(\mathcal{PT}), charge conjugation and parity (\mathcal{CP}) and \mathcal{CP}T
transformations to varius equations of generalized fields of dyons, it is shown
that the corresponding dynamical quantities and equations of dyons are
invariant under these discrete symmetries.
Abstract Key words- parity, time reversal, charge-conjugation, dyons
Abstract PACS No.- 14.80 Hv
Center or Limit Cycle: Renormalization Group as a Probe
Based on our studies done on two-dimensional autonomous systems, forced
non-autonomous systems and time-delayed systems, we propose a unified
methodology - that uses renormalization group theory - for finding out
existence of periodic solutions in a plethora of nonlinear dynamical systems
appearing across disciplines. The technique will be shown to have a non-trivial
ability of classifying the solutions into limit cycles and periodic orbits
surrounding a center. Moreover, the methodology has a definite advantage over
linear stability analysis in analyzing centers
Multiple Front Propagation Into Unstable States
The dynamics of transient patterns formed by front propagation in extended
nonequilibrium systems is considered. Under certain circumstances, the state
left behind a front propagating into an unstable homogeneous state can be an
unstable periodic pattern. It is found by a numerical solution of a model of
the Fr\'eedericksz transition in nematic liquid crystals that the mechanism of
decay of such periodic unstable states is the propagation of a second front
which replaces the unstable pattern by a another unstable periodic state with
larger wavelength. The speed of this second front and the periodicity of the
new state are analytically calculated with a generalization of the marginal
stability formalism suited to the study of front propagation into periodic
unstable states. PACS: 47.20.Ky, 03.40.Kf, 47.54.+rComment: 12 page
Propagation and Structure of Planar Streamer Fronts
Streamers often constitute the first stage of dielectric breakdown in strong
electric fields: a nonlinear ionization wave transforms a non-ionized medium
into a weakly ionized nonequilibrium plasma. New understanding of this old
phenomenon can be gained through modern concepts of (interfacial) pattern
formation. As a first step towards an effective interface description, we
determine the front width, solve the selection problem for planar fronts and
calculate their properties. Our results are in good agreement with many
features of recent three-dimensional numerical simulations.
In the present long paper, you find the physics of the model and the
interfacial approach further explained. As a first ingredient of this approach,
we here analyze planar fronts, their profile and velocity. We encounter a
selection problem, recall some knowledge about such problems and apply it to
planar streamer fronts. We make analytical predictions on the selected front
profile and velocity and confirm them numerically.
(abbreviated abstract)Comment: 23 pages, revtex, 14 ps file
An overview of the Jordanian oil shale: its chemical and geologic characteristics, exploration, reserves and feasibility for oil and cement production
Abstract
Oil shale is the most abundant fossil energy resource discovered in Jordan, ranking third after the USA and Brazil in terms of oil shale reserves. This asset is considered to be Jordan's most extensive domestic fossil-fuel source. The identified reserves of this oil shale are huge and sufficient to satisfy the national energy needs for hundreds of years. Numerous geologic studies have shown that the country contains several oil shale deposits. These deposits are regarded as the richest in organic bituminous marl and limestone that occur at shallow depth. Jordanian oil shale is generally of a good quality, with relatively low ash and moisture contents, a gross calorific value of 7.5 MJ/kg, and an oil yield of 8 to 12%. The spent shale has residual carbon content that may be burned to produce further energy, and ash that can be used for cement and building materials. The current study summarizes the results of the former feasibility studies and discuses the scope of future usage of Jordanian oil shale. The value of this oil shale and its associated products is highlighted herein
Shell evolution approaching the N=20 island of inversion : Structure of 26Na
The levels in 26Na with single particle character have been observed for the first time using the d(25Na, pγ) reaction at 5 MeV/nucleon. The measured excitation energies and the deduced spectroscopic factors are in good overall agreement with (0+1)hω shell model calculations performed in a complete spsdfp basis and incorporating a reduction in the N=20 gap. Notably, the 1p3/2 neutron configuration was found to play an enhanced role in the structure of the low-lying negative parity states in 26Na, compared to the isotone 28Al. Thus, the lowering of the 1p3/2 orbital relative to the 0f7/2 occurring in the neighbouring Z=10 and 12 nuclei - 25,27Ne and 27,29Mg - is seen also to occur at Z=11 and further strengthens the constraints on the modelling of the transition into the island of inversion
The design, construction, and commissioning of the KATRIN experiment
The KArlsruhe TRItium Neutrino (KATRIN) experiment, which aims to make a direct and model-independent determination of the absolute neutrino mass scale, is a complex experiment with many components. More than 15 years ago, we published a technical design report (TDR) [1] to describe the hardware design and requirements to achieve our sensitivity goal of 0.2 eV at 90% C.L. on the neutrino mass. Since then there has been considerable progress, culminating in the publication of first neutrino mass results with the entire beamline operating [2]. In this paper, we document the current state of all completed beamline components (as of the first neutrino mass measurement campaign), demonstrate our ability to reliably and stably control them over long times, and present details on their respective commissioning campaigns
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